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World Congress on Biosensors 2014

World Congress on Biosensors 2014
Biosensors 2014

Friday, 25 November 2011

PhD Nanobioreactors - Start date: April 2012

Supervisors: Professor Anthony PF Turner and Dr. Ashutosh Tiwari Intelligent nanobioreactors for auto-switchable bio-catalysis Applications are invited for a 4-year salaried PhD position to study the design and development of novel auto-switchable nanobioreactors to produce positively responding nano-surfaces by creating unique "zipper" nanoarchitectures. The zipper consists of a polymeric donor branch and a polymeric receptor branch, which will be rationally assembled based on a stoichiometric donor-receptor interaction. Model reactions, with applications in both analysis (e.g. biosensors) and energy production, (e.g. biological fuel cells) will be studied as proof-of-principle platforms in the areas of bioanalysis and biocatalysis.
The position is sponsored by the Swedish Research Council, the principal research funding agency in Sweden, and will be carried out in the

Informal enquiries should be directed to Dr. Ashutosh Tiwari (+46 (0) 13 282395; ashutosh.tiwari@liu.se ) or Prof. Anthony PF Turner, anthony.turner@liu.se . See also https://www.ifm.liu.se/applphys/biosensors-and-bioelectro/

This studentship is available from April 2012, and provides full support for tuition fees in addition to a salary (about Euro 30,000 pa before 30% Tax). Applicants should have master degree in Biotechnology/ Chemistry/ Biochemistry/ Physics or a related discipline.

Closing date: 6 January 2012  
Biosensors and Bioelectronics Centre, which is a division within the Department of Physics, Chemistry and Biology at Linköping University, Sweden URL: www.ifm.liu.se/biosensors

News from the Elsevier Chemistry group

1
Win a free delegate pass for the 13th Tetrahedron Symposium. Click here for more information:

2.
Coming soon… In 2012 the 13th Tetrahedron Symposium will take place in two different locations; one in Europe and one in Asia. For the Europe one visit: www.tetrahedron-symposium.elsevier.com. The website for the Asia one is still under construction but if you would like to keep up-to-date, sign up here:

3.
Win a free delegate pass for the Colloids and Nanomedicine 2012 conference. Click here for more information:

4.
Ahmed Zewail Prize 2013 – Call for Nominations!
We are delighted to announce the 4th Ahmed Zewail Prize in Molecular Sciences.  The Ahmed Zewail Prize in Molecular Sciences is awarded on a biennial basis to individual scientists who have made significant and creative contributions, particularly those of a fundamental nature, to any of the disciplines of molecular sciences. The awardee’s research activities may cover theoretical and/or experimental aspects of studies in all phases of matter and biological systems.

5.
Winners of the Tetrahedron Young Investigator Awards 2012
Prof B.G. Davis and Prof Zhang-Jie Shi win the Tetrahedron Young Investigator Awards 2012. Nominations are now being accepted for the 2013 Award. Click here for more information: http://www.elsevier.com/wps/find/P04_116.cws_home/tet_awards#awards2012

6.
Tetrahedron Prize for Creativity in Organic Chemistry
The Tetrahedron Prize for Creativity in Organic Chemistry for 2011 has been awarded to Professor Dr. Manfred T. Reetz, Max-Planck-Institut fur Kohlenforschung, Honorary Professor at Ruhr-Universitat Bochum. The Tetrahedron Prize will presented to Professor Reetz at the Fall 2012 ACS National Meeting in Philadelphia, USA. Call for Nominations!  Click here to submit a nomination for the 2012 prize: http://www.elsevier.com/wps/find/P04_116.cws_home/tetprize#3

Thursday, 24 November 2011

Just Published: Journal of Chromatography A

A new issue of this journal has just been published. To see abstracts of the papers it contains (with links through to the full papers) click here:
Selected papers from the latest issue:

Thin-film octadecyl-silica glass coating for automated 96-blade solid-phase microextraction coupled with liquid chromatography-tandem mass spectrometry for analysis of benzodiazepines

24 November 2011, 00:20:19Go to full article
Publication year: 2011
Source: Journal of Chromatography A, Available online 23 November 2011
Fatemeh S. Mirnaghi, Maria Rowena N. Monton, Janusz Pawliszyn
A thin-film octadecyl (C18)-silica glass coating was developed as the extraction phase for an automated 96-blade solid-phase microextraction (SPME) system coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS). Various factors (e.g., sol-gel composition and aging time, coating preparation speed, coating thickness, and drying conditions) affecting the quality the C18-silica glass thin-film coating were studied and optimized. The results showed that the stability and durability of the coating are functions of the coating thickness and drying conditions. Coating thickness is controlled by sol-gel composition, aging time and the withdrawal speed in the dipping method. Automated sample preparation was achieved by using a robotic autosampler that enabled simultaneous preparation of 96 samples in a 96-well plate format. Under the optimum SPME conditions the proposed system requires a total 140 min for preparation of all 96 samples (i.e., 30 min preconditioning, 40 min equilibrium extraction, 40 min desorption and 30 min carry over step). The performance of the C18-silica glass 96-blade SPME system was evaluated for high-throughput analysis of benzodiazepines from phosphate-buffered saline solution (PBS) and human plasma, and the reusability, repeatability, and validity of the system were evaluated. When analysing spiked PBS and human plasma, the inter–blade reproducibility for four benzodiazepines was obtained in the ranges of 4-8% and 9-11% RSD (relative standard deviation), respectively, and intra-blade reproducibility were in the ranges of 3-9% and 8-13% RSD, respectively. The limits of detection and quantitation for plasma analysis were in the ranges of 0.4-0.7 ng/mL and 1.5-2.5 ng/mL for all four analytes.

Highlights

► We examined a thin-film octadecyl (C18)-silica glass coating for high throughput extraction of clinical samples ► high-quality sol-gel-based coating was obtained ► device was used over 100 times for complex biological matrices analysis ► Extraction time was less than 1.5 minutes per sample.

Modelling and optimisation of preparative chromatographic purification of europium

24 November 2011, 00:20:19Go to full article
Publication year: 2011
Source: Journal of Chromatography A, Available online 23 November 2011
Frida Ojala, Mark Max-Hansen, Dejene Kifle, Niklas Borg, Bernt Nilsson
A model commonly used to describe the separation of biomolecules was used to simulate the harsh environment when eluting neodymium, samarium, europium and gadolinium with a hot acid. After calibration, the model was used to optimise the preparative separation of europium, as this is the most valuable of the four elements. A kinetic dispersive model with a Langmuir mobile phase modulator isotherm was used to describe the process. The equilibration constant, the stoichiometric coefficient and the column capacity for the components were calibrated. The model fitted the experimental observations well. Optimisation was achieved using a differential evolution method. As the two objective functions used in optimising the process, productivity and yield, are competing objectives, the result was not a single set point but a Pareto front.

Highlights

► Modelling of preparative separation of the REE using a strong acid. ► Cerium was a good substitute to the expensive elements in overloaded experiments. ► Optimisation of Eu separation regarding yield and productivity. ► It is possible to model and optimise the harsh system when separating small ions.

A two-dimensional, heart-cutting preparative gas chromatograph facilitates highly-resolved single-compound isolations with utility towards compound-specific natural abundance radiocarbon (C) analyses

24 November 2011, 00:20:19Go to full article
Publication year: 2011
Source: Journal of Chromatography A, Available online 23 November 2011
Gregory Ian Ball, Li Xu, Ann P McNichol, Lihini I. Aluwihare
Motivated by the need to develop clean, high purity preparative enrichments of individual compounds for micro-scale compound-specific natural abundance isotope and radiocarbon (C) analyses, we describe a new two-dimensional, heart-cutting, low-bleed, three-oven,singleGC preparative system, demonstrate its resolving capabilities as applied to a typically complex environmental sample matrix, and investigate the robustness with which it preserves the authigenicC/C andC/C ratios of individual compounds it targets for preparative enrichment. The system is comprised of a programmable temperature vaporizing (PTV) inlet, a single GC oven, two modular, door-mounted, resistively-heated low thermal mass (LTM) columns, a preparative fraction collector (PFC) and a Deans pneumatic switching device which facilitates heart-cutting between the system's 1° and 2° chromatographic dimensions. Further, the system's inlet and trapping parameters are optimized for the efficient preparative enrichment of the methyl ether and ester derivatives of the lignin phenol compound class. The lignin phenols include such compounds as the vanillyl and syringyl aldehydes, ethanones, and acids and are unrivaled biomarkers of terrestrial organic matter, some of which are also important components of fragrances and flavors. Using this suite of compounds, the suitability of this augmented preparative capillary GC (PCGC) system was investigated for micro-scale compound-specific (CS) stable isotope and natural abundance radiocarbon analyses (RA). Analysis of a > 300 injection enrichment scheme reveals the instrument to fractionateC in predictable ways and to preserve the authigenic ΔC of compounds it targets for preparative enrichment to within 6.7 ± 5.0 ‰, demonstrating the promising new utility of such systems towards micro-scale CSRA investigations for which clean and high resolution separation techniques are prerequisite.

Highlights

► 2-D, heart-cutting prep-GC offers augmented resolving power over traditional setups. ► μg-scale preparative compound isolations by 2-D prep-GC for radiocarbon analysis. ► PCGC optimization conditions for efficient enrichment of lignin-related compounds. ► Low column bleed implementation of preparative capillary gas chromatography (PCGC).

Microwave-assisted purge-and-trap extraction device coupled with gas chromatography and mass spectrometry for the determination of five predominant odors in sediment, fish tissues, and algal cells

24 November 2011, 00:20:19Go to full article
Publication year: 2011
Source: Journal of Chromatography A, Available online 23 November 2011
Xuwei Deng, Ping Xie, Min Qi, Gaodao Liang, Jun Chen, ...
Off-flavors are among the most troublesome compounds in the environment worldwide. The lack of a viable theory for studying the sources, distribution, and effect of odors has necessitated the accurate measurement of odors from environmental compartments. A rapid and flexible microwave-assisted purge-and-trap extraction device for simultaneously determining five predominant odors, namely, dimethyltrisulfide, 2-methylisoborneol, geosmin, β-cyclocitral and β-ionone, from the primary sources and sinks is demonstrated. This instrument facilitates the extraction and concentration of odors from quite different matrices simultaneously. This device is a solvent-free automated system that does not require cleaning and is timesaving. The calibration curves of the five odor compounds showed good linearity in the range of 1 to 500 ng/L, with correlation coefficients above 0.999 (levels = 7) and with residuals ranging from approximately 77% to 104%. The limits of detection (S/N = 3) were below 0.15 ng/L in algae sample and 0.07 ng/g in sediment and fish tissue samples. The relative standard deviations were between 2.65% and 7.29% (n = 6). Thus the proposed design is ready for rapid translation into a standard analytical tool and is useful for multiple applications in the analysis of off-flavors.

Highlights

► In this study, a new online instrument was developed for the determination of odors. ► This instrument is an automated solvent free system and requires no clean-up step. ► Extraction and concentration of odors can be performed simultaneously. ► A method was developed by using the instrument for the analysis of odors from environment matrices. ► This method has been validated with excellent results.

Stem cell qualified mouse Leukemia Inhibitory Factor (mLIF)

AMSBIO has added mouse Leukemia Inhibitory Factor (mLIF) to its extensive range of stem cell research products. Functionally tested with mouse ES cells, the affordably-priced AMSBIO recombinant mLIF combines both high quality and high activity.

Mouse Leukemia Inhibitory Factor is a lymphoid factor involved in a number of biological processes including neural and hematopoietic cell differentiation, bone and fat metabolism, and mitogenesis of certain factor dependent cell lines. Mouse Leukemia Inhibitory Factor has a variety of effects on different cell types in vitro, inhibiting the differentiation of embryonic stem cells and promoting the survival and/or proliferation of primitive hematopoietic precursors and primordial germ cells. The properties of this protein make it essential for culturing stem cells, enabling the long-term maintenance and propagation of undifferentiated mouse embryonic and induced pluripotent cells.

Research proven to deliver outstanding results - each batch of mLIF from AMSBIO is analyzed for purity ensuring very low endotoxin levels and the absence of pyrogenic and pro-inflammatory contaminants. Each batch is tested on mouse ES cells for plating efficiency, colony formation, morphology and maintenance of the undifferentiated state.

The new recombinant mLIF is part of a range of AMSBIO stem cell products that includes mouse ES cells and mouse feeder cells, as well as qualified media and serum that offer reproducible performance and high consistency from batch-to-batch.

For further information please visit www.amsbio.com/Mouse-Leukemia-Inhibitory-Factor-LIF.aspx or contact AMSBIO on +44-1235-828200 / +1-949-768-8365 or email info@amsbio.com

Wednesday, 23 November 2011

Pharmaceutical packaging products benefit from firm yet flexible polymer

Porvair Filtration Group is at the forefront of new material development and products for the medical, pharmaceutical and life science markets. The company's range of proprietary BioVyon™ sintered porous plastic materials and products have been developed using novel technologies to help advance the achievable technical boundaries in these markets.

Included in the BioVyon™ range is porous polyethylene, a proprietary sintered material that delivers superior strength with reduced brittleness compared to standard polyethylene. These material characteristics, combined with elasticity, provide firm flexibility for easy insertion and excellent interference fit for use in pharmaceutical product packaging such as medicinal bottle vents and powder inlet supports and outlet vents in bicarbonate dialysis cartridges. Precisely manufactured to current good manufacturing practices (cGMP) in ISO-accredited clean rooms, BioVyon™ materials meet FDA approval and USP Class VI for biocompatibility and biosafety.

As a leading manufacturer of sintered porous plastics, Porvair Filtration Group offers a variety of core manufacturing competencies that ensure products meet customer requirements. These include fabrication of materials comprising shape cutting using 2D routing, rotary disc cutting or punching and assembly of products by hand, automation, bonding using heat, adhesives and ultrasonic welding. Facilities for low volume technical moulding with all engineering plastics (including PEEK) and an over moulding capability are also available.

Driven by market requirements, Porvair's range of BioVyon™ materials are continuously expanding and are available to both OEM and end user customers. To discuss your application please visit our stand at CompaMed / Medica 2011 or contact Porvair Filtration Group on +44-1489-864330 / +1-804-550-1600 / email info@porvairfiltration.com.

Misonix Laboratory Fume Hoods and Forensic Division acquired by Mystaire, Inc.

Mystaire™ Inc.,  announces the acquisition of the Scientific Laboratory Fume Hoods and Forensic Product Division of Misonix, Inc.    Mystaire™ will manufacture the newly acquired product line under the name Mystaire™ Misonix.  All manufacturing, sales,  and support functions will be handled at the Mystaire ™corporate headquarters located in Creedmoor, NC USA.  
“We are extremely excited to continue the work that Misonix began many years ago.  We will strive to build upon the quality platform that Misonix has established in the marketplace.  We will focus on the safety needs of laboratory and law enforcement professionals worldwide, with the goal of providing the best possible solutions and service to the industry” said Mystaire™ Misonix president Mark Leath.
Mystaire™ Misonix offers a full range of containment solutions for general chemistry, molecular biology, pharmaceutical, forensic, and academic research and manufacturing.  Visit our website at www.mystaire.com for the complete product offering.  

Tuesday, 22 November 2011

JEOL Chemist Receives Prestigious Anachem Award

JEOL USA Mass Spectrometry Product Manager, Dr. Robert (Chip) Cody, has received the prestigious Anachem Award, given by the Association of Analytical Chemistry for his contributions to the development of organic mass spectrometry. The award was presented at the Federation of Analytical Chemical and Spectroscopy Societies (FACSS) meeting in Las Vegas, Nevada, where Dr. Cody gave a plenary lecture entitled Massive Changes: Not just your grandma’s mass spectrometer any more, an historical talk, on Monday, October 3. He was honored during a special session by five speakers who presented on mass spectrometry topics relevant to his work.

Through his inventions and his efforts to commercialize them, Dr. Cody has provided the scientific community with new tools to more precisely and efficiently characterize a broad range of materials. Examples include: laser ablation and desorption, the DART (Direct Analysis in Real Time) ion source, trapped-ion MS/MS techniques and other creative combinations of chromatography, ionization sources, and mass analyzers. He has also contributed to the advancement of analytical chemistry through his service to professional scientific organizations and through his mass spectrometry courses. 

Dr. Cody has worked at JEOL USA since 1989. Upon completion of his Ph.D. at Purdue University in Indiana, he joined Nicolet Instruments in Madison, Wisconsin in 1982. He received his Bachelor’s Degree from Roanoke College in Salem, Virginia in 1976.   

The Anachem Award was established in 1953 and is presented annually to an outstanding analytical chemist. Only a few recipients other than Dr. Cody have been from an instrument company.

State-of-the-Art Condenser Enhances Lyophilisation Results

Genevac announces the new SuperCool 75 - a state-of-the-art condenser that in conjunction with its HT-12 High Throughput Evaporator has been proven to set a new benchmark for enhanced evaporation and lyophilisation results.

Drying HPLC purification fractions, principally comprising water and acetonitrile, is a routine yet essential task in many pharmaceutical laboratories.  The requirement is to dry the samples to a powder form, such that samples can be accurately weighed, easily sub-sampled and redissolved.  To provide a rapid, high-throughput alternative to freeze drying of such samples - Genevac developed its proprietary fast lyophilisation (LyoSpeed™) methodology for use on the HT-12 Evaporator.  While the LyoSpeed™ has traditionally worked well for hydrophilic samples - difficulties may arise where the sample cannot dissolve in only water.  In such situations, when the organic solvent is removed, the sample crashes out forming an oil which until now required further processing to achieve the desired dry powder form.

The SuperCool 75 chills to -75C and operates at higher power than any other commercially available condenser, opening the door to greatly improved results with the Genevac LyoSpeed fast lyophilisation process for HPLC fractions. Customer trials have shown that the Genevac HT-12 Evaporator / SuperCool 75 combination produces powdered lyophilisation samples using the LyoSpeed methodology from even the most difficult to handle samples with a success rate as high as 95%.

To download a technical paper on high throughput lyophilisation of HPLC samples from mixed aqueous : organic solutions please visit www.evaporatorinfo.com/info5.htm or contact Genevac on +44-1473-240000 / +1-845-255-5000 / salesinfo@genevac.co.uk for a product datasheet.

Monday, 21 November 2011

Just Published: Journal of Chromatography A

A new issue of this journal has just been published. To see abstracts of the papers it contains (with links through to the full papers) click here:
Selected papers from the latest issue:

Determination of sulfonamides in food samples by membrane-protected micro-solid phase extraction coupled with high performance liquid chromatography

20 November 2011, 23:45:07Go to full article
Publication year: 2011
Source: Journal of Chromatography A, Available online 19 November 2011
Jiangeng Huang, Juanjuan Liu, Cong Zhang, Jiaojiao Wei, Li Mei, ...
In the present study, a simple and sensitive extraction method based on polypropylene membrane-protected micro-solid phase extraction (MP-μ-SPE) has been developed for analysis of sulfonamides in food samples. Poly (methacrylic acid-ethylene glycol dimethacrylate) (p-MAA-EDMA) was synthesized using orthogonal array experimental design, optimized with three factors at four levels and evaluated on yield, hydrophobic and cation-exchange properties. The optimized p-MAA-EDMA was then employed as the sorbent in the MP-μ-SPE for extraction of sulfonamides from milk and chicken muscle samples, followed by high performance liquid chromatographic analysis with ultraviolet detection. Under optimized extraction conditions, good linearities (0.010-1.0 μg mLwith r>0.9900), low limits of detection (0.38-0.62 ng mL), and acceptable intra-day (2.7-13.7%) and inter-day (6.7-15.2%) relative standard deviations were obtained. It was demonstrated to be an effective approach to handle semi-solid/solid samples with good resistance to interference from “dirty” samples.

Highlights

► MP-μ-SPE was developed for food analysis. ► Synthesis of P-MAA-EDMA was optimized using orthogonal array experimental design. ► The materials were evaluated by the yield, hydrophobic and ion-exchange properties. ► The optimized p-MAA-EDMA was used as the sorbent in MP-μ-SPE of sulfonamides. ► It was effective to handle semi-solid/solid samples with good resistance to matrix.

COMBINED USE OF ISOPROPYLAMINE AND TRIFLUOROACETIC ACID IN METHANOL-CONTAINING MOBILE PHASES FOR CHIRAL SUPERCRITICAL FLUID CHROMATOGRAPHYs

20 November 2011, 23:45:07Go to full article
Publication year: 2011
Source: Journal of Chromatography A, Available online 19 November 2011
Katrijn De Klerck, Debby Mangelings, David Clicq, Filip De Boever, Yvan Vander Heyden
In chiral supercritical fluid chromatography (SFC), mobile-phase additives are often used to improve enantioseparations and peak shapes. An acidic or basic additive is chosen, depending on the nature of the compound. This work highlights the simultaneous use of the acidic additive trifluoroacetic acid (TFA) and the basic additive isopropylamine (IPA) in supercritical fluid chromatography for enantioseparations. To evaluate the combination of TFA and IPA, 59 chiral pharmaceutical compounds were analyzed on four polysaccharide-based chiral stationary phases (CSPs):LuxCellulose-1, LuxCellulose-2, LuxCellulose-4 and LuxAmylose-2. The results show that an important increase in enantioselectivity of the chromatographic system can occur when combining trifluoroacetic acid and isopropylamine in the mobile phase (MP), compared to the individual use of these additives. However, the combination of isopropylamine and trifluoroacetic acid in a supercritical methanol-containing mobile phase can also lead to problems as a result of the formation of salt complexes between the two additives. Combining the additives trifluoroacetic acid and isopropylamine and taking the appropriate measures to avoid salt formation,i.e.reducing the additives’ concentrations, can lead to simpler chiral SFC screening conditions that display even broader enantioselectivity.

Highlights

► Investigation of isopropylamine and trifluoroacetic acid as additives in SFC ► Additives combined together in methanol-based mobile phase for chiral screenings ► Broader enantioselectivity is achieved compared to individual use of the additives ► Formation of salt complexes between additives, their precipitation is problematic ► Lowering the concentration allows combined use of isopropylamine and trifluoroacetic acid

Effect of varying flow regimes upon elution behaviour and apparent molecular characteristics and hydrodynamic properties of amylopectin isolated from normal corn starch using Asymmetrical Flow Field-Flow Fractionation

20 November 2011, 23:45:07Go to full article
Publication year: 2011
Source: Journal of Chromatography A, Available online 19 November 2011
Shazia Juna, Anton Huber
A detailed study of the elution behaviour, apparent molecular characteristics and hydrodynamic properties of amylopectin-type fraction (isolated from normal corn starch) in aqueous media employing asymmetrical flow field-flow fractionation (AF4) was undertaken by systematically varying the channel flow (Fch), cross flow (Fcr) and Fcr/Fchratios. Distributions of apparent molar masses and radii of gyration, mass recoveries and hydrodynamic radii decreased as a function of increasing Fcrat a fixed Fch, due to the increase in the retention of amylopectin-type fraction in the AF4 channel. Increased retention of the amylopectin-type fraction in the AF4 channel was also observed at low Fchand high Fcr/Fchratios. Large amylopectin-type molecules/particles (possibly aggregates) eluted at high Fch, low Fcrand low Fcr/Fchratios.

Highlights

► Elution behaviour of amylopectin (normal corn) using AF4. ► Influence of cross flow rates upon retention of amylopectin ► Effect of flow rates on the aggregation and hydrodynamic properties of amylopectin

Ultra-preconcentration and determination of thirteen organophosphorus pesticides in water samples using solid-phase extraction followed by dispersive liquid-liquid microextraction and gas chromatography with flame photometric detection

20 November 2011, 23:45:07Go to full article
Publication year: 2011
Source: Journal of Chromatography A, Available online 19 November 2011
Soheila Samadi, Hassan Sereshti, Yaghoub Assadi
An ultra-preconcentration technique composed of solid-phase extraction (SPE)anddispersive liquid-liquid microextraction (DLLME) coupled with gas chromatography-flame photometric detection (GC-FPD) was used for determination of thirteen organophosphorus pesticides(OPPs) includingphorate, diazinon, disolfotane, methyl parathion, sumithion, chloropyrifos, malathion, fenthion, profenphose, ethion, phosalone, azinphose-methyl and co-ral in aqueous samples. The analytes were collected from large volumes of aqueous solutions (100 mL) into 100 mg of a SPE C18sorbent.. The effective variables of SPE including type and volume of elution solvent, volume and flow rate of sample solution, and salt concentration were investigated and optimized.Acetone was selected as eluent in SPE and disperser solvent in DLLME and chlorobenzene was used as extraction solvent. Under the optimal conditions, the enrichment factors were between 15160-21000 and extraction recoveries were 75.8 to 105.0%. The linear range was 1-10000 ngLand limits of detection(LODs) were between 0.2 and 1.5 ngL. The relative standard deviations (RSDs) for 50 ngLof OPPs in water with and without an internal standard, were in the range of 1.4-7.9% (n = 5) and 4.0-11.6%, respectively. The relative recoveries of OPPs from well and farm watersat spiking levels of 25 and 250 ngLwere 88-109%.

Highlights

► We introduced SPE-DLLME-GC-FPD for determination of OPPs in water samples. ► The method's advantages are high EF, low LOD, wide LDR and short analysis time. ► It offers ultra preconcentration factor and excellent performance in complex matrices.

Purification of Coomassie Brilliant Blue G-250 by Multiple Dual Mode Countercurrent Chromatography

20 November 2011, 23:45:07Go to full article
Publication year: 2011
Source: Journal of Chromatography A, Available online 19 November 2011
Nazim Mekaoui, Joseph Chamieh, Vincent Dugas, Claire Demesmay, Alain Berthod
Commercial samples of Coomassie Brilliant Blue G 250 (CBB) were not pure enough to give reliable results when used as indicator of amine content in biological material. The polar and apolar impurities produce unacceptable biases in the results. Counter current chromatography (CCC) was used to purify significant amounts of CBB. The liquid system heptane/1-butanol/water 2:3:4 v/v was appropriate to separate crude CBB in three groups of components: polar, partitioning in the aqueous lower phase, intermediate, partitioning well between the aqueous and organic phases, and apolar, preferring greatly the organic phase. The dual-mode way of using a CCC chromatograph was found appropriate for the separation injecting the crude CBB in the middle of a two coil CCC instrument. A multi dual-mode purification was performed allowing to eliminate the polar impurities in the aqueous phase at the column tail and the apolar ones in the organic phase at the column head, trapping the purified dye inside the CCC column. 200 mg of purified CBB were obtained from 1 g of crude CBB in 3 hours using as little as 150 mL of butanol and 70 mL of heptane with 200 mL of water. The purified CBB gave total satisfaction in testing amine content in polyclonal antibody containing monolith pipettes.

Optibrium Expands StarDrop Availability with Apple Mac Compatibility

Optibrium, a provider of software solutions for drug discovery, today launches StarDrop 5.1, an upgraded version of its innovative support tool which helps drug discovery scientists to guide key decisions in drug discovery and quickly achieve successful project outcomes. As a result of this upgrade, StarDrop’s unique capabilities to guide the design and selection of high quality, novel compounds are now available on the Apple Mac, a reflection of the increasing popularity of Macs within the industry.
The revolutionary StarDrop 5.1 is a powerful yet user friendly software package which combines predictive capabilities with intuitive approaches to quickly and confidently target compounds with a good balance of properties, thereby reducing wasted effort and speeding progress to identify effective lead and candidate drugs. StarDrop’s unique approach to ‘multi-parameter optimisation’ explicitly accounts for the uncertainty in drug discovery data, whether due to experimental variability or predictive error, to provide scientists with a rigorous, objective analysis on which to make rational decisions.
As well as compatibility with the Apple Mac, StarDrop 5.1 brings a number of significant enhancements to existing features of StarDrop. For example, there is a new method for creating ‘chemical space’ visualizations based on the latest machine learning algorithm for ‘visual clustering’, that helps to easily explore the diversity of a project’s chemistry and identify ‘hot spots’ of high quality chemistry for further investigation.
There are also improvements to StarDrop’s plug-in modules:  The Auto-Modeller™ sees the addition of  the ‘Random Forests’ technique to its extensive repertoire for building predictive models tailored to a project’s chemistry and data. The addition of this new method has also led to improved QSAR models in the ADME QSAR module, which provides predictions of key ADME properties. StarDrop’s P450 metabolism module has been upgraded to provide improved prediction of regioselectivity and lability of metabolism by Cytochrome P450 enzymes, specifically around N-oxidation pathways. Finally, in response to user feedback on the new Nova™ module, further advances allow the generation of novel, relevant compounds ideas, prioritised against a project’s required property profile, starting from multiple initial structures and filtered according to user-specified rules to avoid unwanted substructures.
Dr. Matthew Segall, CEO of Optibrium, explains “These latest developments within StarDrop 5.1 demonstrate Optibrium’s commitment to deliver leading-edge technology while simultaneously responding to user feedback in order to ensure that it is accessible in the most user-friendly way. We work with drug discovery scientists, project leaders and R&D directors to provide tools that support confident decision-making to focus resources and improve efficiency.”
For more information about StarDrop 5.1 and Optibrium’s software solutions please visit www.optibrium.com, alternatively please call +44 (0) 1223 815 900 or email info@optibrium.com

Affordable, High Quality Cell Culture Flasks

Porvair Sciences has announced a new range of affordable, high quality cell culture flasks with design features to streamline your cell culture workflow.

Combining the unrivalled optical purity of high-pressure molded 100% USP Class VI virgin crystal polystyrene with a patented low-pressure gas plasma surface treatment allows cells to adhere more efficiently to the surface by reducing its hydrophobicity. Highly polished moulds and rigorous quality control ensure that you get perfect visualization every time.

The new range of culture flasks are designed with novel features including molded graduations in the flask walls, opaque areas for laboratory markers and sector division marks on the dishes. Both vented and sealed caps are available for all sizes of flask.

Production of Porvair cell culture flasks is carried out in a Class 10000 / ISO Class VII clean environment to ISO 9001:2008 and EN ISO 13485:2003 manufacturing standards to ensure all products are free from DNA/RNA, DNase/RNase and Pyrogen contamination.

Established in 1992, Porvair Sciences Ltd. expertise in microplate technology and manufacturing covers scientific fields including Life Sciences, Drug Discovery, Combinatorial Chemistry, Solid Phase Extraction, Protein Purification, High Throughput Screening, Proteomics and Genomics.  Porvair Sciences Ltd. is a wholly owned subsidiary of Porvair plc.

For further information on the cell culture flasks please contact Porvair Sciences on telephone +44-1372-824290, email int.sales@porvair-sciences.com or visit the website at http://www.epigeneticsexpress.com/

Friday, 18 November 2011

Just Published: Talanta

A new issue of this journal has just been published. To see abstracts of the papers it contains (with links through to the full papers) click here:
Talanta
Selected papers from the latest issue:

Supercritical fluid extraction from spent coffee grounds and coffee husks: antioxidant activity and effect of operational variables on extract composition

17 November 2011, 23:48:10Go to full article
Publication year: 2011
Source: Talanta, Available online 16 November 2011
Kátia S. Andrade, Ricardo T. Gonçalvez, Marcelo Maraschin, Rosa Maria Ribeiro-do-Valle, Julian Martínez, ...
The present study describes the chemical composition and the antioxidant activity of spent coffee grounds and coffee husks extracts, obtained by supercritical fluid extraction (SFE) with CO2and with CO2and co-solvent. In order to evaluate the high pressure method in terms of process yield, extract composition and antioxidant activity, low pressure methods, such as ultrasound (UE) and soxhlet (SOX) with different organic solvents, were also applied to obtain the extracts. The conditions for the SFE were: temperatures of 313.15 K, 323.15 K and 333.15 K and pressures from 100 to 300 bar. The SFE kinetics and the mathematical modeling of the overall extraction curves (OEC) were also investigated. The extracts obtained by LPE (low pressure extraction) with ethanol showed the best results for the global extraction yield (X0) when compared to SFE results. The best extraction yield was 15 ± 2% for spent coffee grounds with ethanol and 3.1 ± 04% for coffee husks. The antioxidant potential was evaluated by DPPH method, ABTS method and Folin-Ciocalteau method. The best antioxidant activity was showed by coffee husk extracts obtained by LPE. The quantification and the identification of the extracts were accomplished using HPLC analysis. The main compounds identified were caffeine and chlorogenic acid for the supercritical extracts from coffee husks.

Highlights

► Coffee industry residues; ► Antioxidant sources; ► Increase the aggregated value of agroindustrial residues; ► The composition of coffee residue extracts suggests a high potential for industrial application; ► The supercritical technology was efficient for caffeine extraction from the residues.

Determination Of Carbofuran In Surface Water And Biological Tissue By Sol-Gel Immunoaffinity Extraction And On-Line Preconcentration/Hplc/Uv Analysis

17 November 2011, 23:48:10Go to full article
Publication year: 2011
Source: Talanta, Available online 16 November 2011
Luz E. Vera-Avila, Bani P. Márquez-Lira, Marcos Villanueva, Rosario Covarrubias, Gustavo Zelada, ...
A selective and simple analytical method for the trace level determination of carbofuran in complex environmental and biological samples was developed based on immunoaffinity extraction (IAE) followed by on-line preconcentration and HPLC/UV analysis of the purified extract. The immunosorbent for IAE was prepared by sol-gel encapsulation of monoclonal anti-carbofuran antibodies, and was fully characterized for capacity, repeatability, binding strength, binding kinetics and cross-reactivity. Method performance was evaluated with two different types of difficult samples: dam water and methanolic extracts of epithelial cervical-uterine tissue. Linear behavior and quantitative recoveries were obtained from the analysis of samples spiked with carbofuran at 0.2-4 ng/mL (dam water, 50 mL samples) and 10-40 ng/mL (biological tissue extract, 2 mL samples). RSD (n = 7) and detection limits were, respectively, 10.1% (spike 0.40 ng/mL) and 0.13 ng/mL for dam water; 8.5% (spike 20 ng/mL) and 5 ng/mL for the biological tissue extract. The excellent sample purification achieved with the IAE column allows precise and accurate determination of carbofuran in complex matrices, even when using non-selective UV detection in the chromatographic analysis.

Highlights

► An immunosorbent (IS) for carbofuran was prepared by the sol-gel technique ► Main IS properties were: high capacity, strong binding, selective, reproducible ► An immunoaffinity column was then used to extract carbofuran from complex samples ► Extract was further on-line preconcentrated and analyzed by SPE/HPLC/UV ► Good precision, accuracy and sensitivity were achieved with this method

Novel Furo[2,3–d] Pyrimidine Derivative as Fluorescent Chemosensor for HSO4

17 November 2011, 23:48:10Go to full article
Publication year: 2011
Source: Talanta, Available online 16 November 2011
Weijian Xue, Lin Li, Qi Li, Anxin Wu
A class of novel heterocyclic compounds1a−1chas been designed and synthesized. And our initial discovery is that these compounds can effectively recognize HSO4. With the addition of HSO4, a new energy band appears at 360−390 nm in the absorption spectra. The emission spectrum (λex = 328 nm) undergoes an important change in its fluorescent effect in the presence of HSO4. All available data (absorption and emission) strongly support the formation of hydrogen−bonded complexes between1a−1cand HSO4.

An automated approach for analysis of Fourier Transform Infrared (FTIR) spectra of Edible Oils

17 November 2011, 23:48:10Go to full article
Publication year: 2011
Source: Talanta, Available online 16 November 2011
Sim Siong Fong, Ting Woei
This paper reports a computational approach for analysis of FTIR spectra where peaks are detected, assigned and matched across samples to produce a peak table with rows corresponding to samples and columns to variables. The algorithm is applied on a dataset of 103 spectra of a broad range of edible oils for exploratory analysis and variable selection using Self Organising Maps (SOMs) and t-statistics, respectively. Analysis on the resultant peak table allows the underlying patterns and the discriminatory variables to be revealed. The algorithm is user-friendly; it involves a minimal number of tunable parameters and would be useful for analysis of a large and complicated FTIR dataset.

Highlights

► Automated algorithm is used as an alternative approach to analyse FTIR spectra. ► The algorithm detects, assigns and matches peaks automatically. ► The resultant peak table allows exploratory analysis and variable selection. ► This algorithm would be useful when a large volume of data is involved.

New Behavioral Experiment Software

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Thursday, 17 November 2011

Just Published: Journal of Chromatography A

A new issue of this journal has just been published. To see abstracts of the papers it contains (with links through to the full papers) click here:

AMI ANNOUNCES THE 10th ANNUAL POLYETHYLENE FILMS CONFERENCE

Applied Market Information LLC (AMI) will be hosting Polyethylene Films 2012 in Daytona Beach, FL at The Shores Resort & Spa on February 9-10, 2012. This will be the tenth annual edition of this conference focusing on the polyethylene film industry. The headline sponsors this year are Ampacet and Techmer PM, with additional sponsorship by Polyfil.
Polyethylene Films is designed to be an international meeting place for all members of the industry supply chain to discuss ideas and formulate plans for the future.
The conference will begin on day 1 with a market overview, given by AMI’s Research Director, Andrew Reynolds. The first session will cover prime raw materials with presentations from leading chemical companies including The Dow Chemical Company and Total Petrochemicals. During Session 2, discussions will highlight additives with speakers from Unimin, A. Schulman, and Chemtura. Day 1 will conclude with session 3 focusing on ancilary equipment with presentations from NDC Infrared Engineering, Inc., and Next Generation Recycling Machines, Inc. 
All conference attendees are invited to attend a networking cocktail reception at the conclusion of the presentations on the first day.
The second day of the conference will begin with session 4 comprised of primary machinery papers from Reifenhauser Inc., Davis Standard LLC, Macchi North America Plastic Machinery, Inc., and Windmoeller & Hoelscher Corporation. The conference will conclude with a fifth session, the Business Forum. Attendees will hear from industry leaders from CMD Corporation, Sealed Air Corporation, and Exxon Mobil. Andrew Reynolds will finish the session with the current status and outlook for the PE film industry in North America.
There will be an exhibition running alongside the conference. The table tops will allow companies to display their services and products to a highly targeted audience. Also, all social gatherings and the cocktail reception will be hosted in the Exhibition Room.
The full conference brochure can be found at http://www.amiplastics-na.com/Events/Event.aspx?code=C449&sec=2239.
For more information on attending or exhibiting at this event, contact Conference Coordinator, Amanda Schaeffer, by emailing as@amiplastics-na.com or by calling +1 610 478 0800.

Streamlining Sample Storage for Donor Organizations and Tissue Banks

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Wednesday, 16 November 2011

Just Published: Analytica Chimica Acta

A new issue of this journal has just been published. To see abstracts of the papers it contains (with links through to the full papers) click here:
Selected papers from the latest issue:

Testing the performance of pure spectrum resolution from Raman hyperspectral images of differently manufactured pharmaceutical tablets

16 November 2011, 00:13:38Go to full article
Publication year: 2011
Source: Analytica Chimica Acta, Available online 15 November 2011
Balázs Vajna, Attila Farkas, Hajnalka Pataki, Zsolt Zsigmond, Tamás Igricz, ...
Chemical imaging is a rapidly emerging analytical method in pharmaceutical technology. Due to the numerous chemometric solutions available, characterization of pharmaceutical samples with unknown components present has also become possible. This study compares the performance of current state-of-the-art curve resolution methods (multivariate curve resolution–alternating least squares, positive matrix factorization, simplex identification via split augmented Lagrangian and self-modelling mixture analysis) in the estimation of pure component spectra from Raman maps of differently manufactured pharmaceutical tablets. The batches of different technologies differ in the homogeneity level of the active ingredient, thus, the curve resolution methods are tested under different conditions. An empirical approach is shown to determine the number of components present in a sample. The chemometric algorithms are compared regarding the number of detected components, the quality of the resolved spectra and the accuracy of scores (spectral concentrations) compared to those calculated with classical least squares, using the true pure component (reference) spectra. It is demonstrated that using appropriate multivariate methods, Raman chemical imaging can be a useful tool in the non-invasive characterization of unknown (e.g. illegal or counterfeit) pharmaceutical products.

Highlights

► MCR-ALS and PMF provide better spectra and concentration maps than SMMA and ► SISAL. ► Homogeneous distribution of a component makes curve resolution much less accurate. ► MCR-ALS can be also well used if a component is homogeneously distributed. ► An unknown product can be characterized regardless how it was manufactured. ► Our results show perspectives in the analysis of unknown (illegal) drugs

Chemistry of ascorbic acid and sulfur dioxide as an antioxidant system relevant to white wine

16 November 2011, 00:13:38Go to full article
Publication year: 2011
Source: Analytica Chimica Acta, Available online 15 November 2011
Célia Barril, Andrew C Clark, Geoffrey R Scollary
The impact of the combined ascorbic acid and sulfur dioxide antioxidants on white wine oxidation processes was investigated using a range of analytical techniques, including flow injection analysis for free and total sulfur dioxide and two chromatographic methods for ascorbic acid, its oxidative degradation products and phenolic compounds. The combination of different analytical techniques provided a fast and simultaneous means for the monitoring of oxidation processes in a model wine system. In addition, the initial mole ratio of sulfur dioxide to ascorbic acid was varied and the model wine complexity was increased by the inclusion of metal ions (copper(II) and iron(II)). Sulfur dioxide was found not to be a significant binder of ascorbic acid oxidative degradation products and could not prevent the formation of certain phenolic pigment precursors. The results provide a detailed insight into the ascorbic acid/sulfur dioxide antioxidant system in wine conditions.

Highlights

► Use of flow injection analysis and liquid chromatography for the monitoring of oxidative processes relevant to white wine. ► A range of sulfur dioxide to ascorbic acid initial mole ratios was used to evaluate the combined effects of the antioxidant system. ► The ascorbic acid degradation products were found to be weak binders of sulfur dioxide under wine conditions.

Kappa-Casein Based Electrochemical and Surface Plasmon Resonance Biosensors for the Assessment of the Clotting Activity of Rennet

16 November 2011, 00:13:38Go to full article
Publication year: 2011
Source: Analytica Chimica Acta, Available online 15 November 2011
Maria A. Panagopoulou, Dimitrios V. Stergiou, Ioannis G. Roussis, George Panayotou, Mamas I. Prodromidis
We report for the first time the development ofkappa-casein (κ-CN)-based electrochemical and surface plasmon resonance (SPR) biosensors for the assessment of the clotting activity of rennet. Electrochemical biosensors were developed over gold electrodes modified with a self-assembled monolayer of dithiobis − N − succinimidyl propionate, while SPR measurements were performed on regenerated carboxymethylated dextran gold surfaces. In both types of biosensor,κ-CN molecules were immobilized onto modified gold surfaces through covalent bonding. In electrochemical biosensors, interactions between the immobilizedκ-CN molecules and chymosin (the active component of rennet) were studied by performing cyclic voltammetry, differential pulsed voltammetry, and electrochemical impedance spectroscopy (EIS) measurements, using hexacyanoferrate(II)/(III) couple as a redox probe.κ-CN is cleaved by rennet at the Phe105 − Met106 bond, producing a soluble glycomacropeptide, which is released to the electrolyte, and the positively charged insolublepara-κ-casein molecule, which remains attached to the surface of the electrode. This induced reduction of the net negative charge of the sensing surface, along with the partial degradation of the sensing layer, results in an increase of the flux of the redox probe, which exists in the solution, and consequently, to signal variations, which are associated with the increased electrocatalysis of the hexacyanoferrate(II)/(III) couple on the gold surface. SPR experiments were performed in the absence of the redox probe and the observed SPR angle alterations were solely attributed to the cleavage of the immobilizedκ-CN molecules. Various experimental variables were investigated and under the selected conditions the proposed biosensors were successfully tried to real samples. The ratios of the clotting power units in various commercial solid or liquid samples, as they are calculated by the EIS-based data, were almost identical to those obtained with a reference method. In addition, EIS measurements showed an excellent reproducibility, lower than 5%.

Highlights

k-CN-based electrochemical and SPR biosensors for the clotting power of rennet are described. ► The proposed biosensors were successfully tested at various commercial rennet samples. ► EIS is more reliable and reproducible than DPV

A risk-based statistical investigation of the quantification of polymorphic purity of a pharmaceutical candidate by solid-stateF NMR

16 November 2011, 00:13:38Go to full article
Publication year: 2011
Source: Analytica Chimica Acta, Available online 15 November 2011
Samantha J Barry, Tran N Pham, Phil J Borman, Andrew J Edwards, Simon A Watson
The DMAIC (Define, Measure, Analyse, Improve and Control) framework and associated statistical tools have been applied to both identify and reduce variability observed in a quantitativeF solid-state NMR (SSNMR) analytical method. The method had been developed to quantify levels of an additional polymorph (Form 3) in batches of an active pharmaceutical ingredient (API), where Form 1 is the predominant polymorph. In order to validate analyses of the polymorphic form, a single batch of API was used as a standard each time the method was used. The level of Form 3 in this standard was observed to gradually increase over time, the effect not being immediately apparent due to method variability. In order to determine the cause of this unexpected increase and to reduce method variability, a risk-based statistical investigation was performed to identify potential factors which could be responsible for these effects. Factors identified by the risk assessment were investigated using a series of designed experiments to gain a greater understanding of the method. The increase of the level of Form 3 in the standard was primarily found to correlate with the number of repeat analyses, an effect not previously reported in SSNMR literature. Differences in data processing (phasing and linewidth) were found to be responsible for the variability in the method. After implementing corrective actions the variability was reduced such that the level of Form 3 was within an acceptable range of ±1% w/w in fresh samples of API.

Highlights

► Investigate a quantitativeF solid-state NMR method for polymorphic purity. ► DMAIC framework used to investigate risk factors and reduce variability. ► Analytical method found to directly affect polymorphism. ► Differences in data processing are responsible for variability in the method. ► Specific processing steps implemented to reduce variability.

One- and two-dimensional GC-MS and HPLC–DAD fingerprints of complex substances: A comparison of classification performance of similar, complexRhizoma Curcumaesamples with the aid of chemometrics

16 November 2011, 00:13:38Go to full article
Publication year: 2011
Source: Analytica Chimica Acta, Available online 15 November 2011
Yongnian Ni, Minghua Mei, Serge Kokot
Many complex natural or synthetic products are analysed either by the GC-MS or HPLC-DAD technique, each of which produces a one-dimensional fingerprint for a given sample. This may be used for classification of different batches of a product. GC-MS and HPLC-DAD analyses of complex, similar substances represented by the three common types of the TCM,Rhizoma Curcumaewere analysed in the form of one- and two-dimensional matrices firstly with the use of PCA, which showed a reasonable separation of the samples for each technique. However, the separation patterns were rather different for each analytical method, and PCA of the combined data matrix showed improved discrimination of the three types of object; close associations between the GC-MS and HPLC-DAD variables were observed. LDA, BP-ANN and LS-SVM chemometrics methods were then applied to classify the training and prediction sets. For one-dimensional matrices, all models indicated that several samples would be misclassified by each training model; the same was observed for each prediction set. However, by comparison, in the analysis of the combined matrix, all models gave 100% classification with the training set, and the LS-SVM calibration also produced a 100% result for prediction, with the BP-ANN calibration closely behind. This has important implications for comparing complex substances such as the TCMs because clearly the one-dimensional data matrices alone produce inferior results for training and prediction as compared to the combined data matrix models. Thus, product samples may be misclassified with the use of the one-dimensional data because of insufficient information.

Highlights

► GC-MS and HPLC-DAD technique were combined to produce two-way fingerprints for the complex materials. ► Supervised chemometrics methods, LDA, BP-ANN and LS-SVM were used for classification. ► More effect information and improved discrimination of the objects were obtained from the combined data matrix models.