This blog has been set up for editors, reviewers, authors and readers of Elsevier's Analytical Chemistry Journals - all of which can be seen below. It will be updated from Monday to Friday with general news and announcements concerning the titles listed on this page. It should be noted that the views or claims made in the news items and feeds are not necessarily those of the Publisher.
World Congress on Biosensors 2014
Biosensors 2014
Monday 15 July 2013
Just Published: Journal of Pharmaceutical and Biomedical Analysis
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:
Publication date: November
2013 Source:Journal of Pharmaceutical and Biomedical Analysis, Volume
85 Author(s): Yun Ling , Zhixiong Li , Mingcang Chen , Zhaolin Sun , Mingsong
Fan , Chenggang Huang Radix Polygalae (RP), the dried root of Polygala
tenuifolia Willd., is a well-known traditional Chinese medicine to mediate
sedative, antipsychotic, cognitive improving, neuroprotective, and
anti-inflammatory therapeutic effects on the central nervous system. In this
work, ultra high-performance liquid chromatography coupled with electrospray
ionization quadrupole time-of-flight tandem mass spectrometry
(UHPLC/ESI-Q-TOF-MS/MS) was established for the separation and characterization
of the chemical constituents in Radix Polygalae and their metabolites in rat
plasma and urine after oral administration. Samples were separated on an Agilent
Zorbax Eclipse Plus-C18 column (100mm×2.1mm, 1.8μm) with 0.1% formic acid
aqueous solution and acetonitrile as the mobile phase under gradient conditions.
Overall, 50 compounds were characterized from the RP, 9 of which are to our
knowledge reported for the first time. In vivo, 10 components and 2 metabolites
were observed in rat plasma, and 27 components and 7 metabolites were detected
in rat urine. The results from this work improve our understanding on the
chemical constituents of RP and their metabolic profiling.
Publication date: October
2013 Source:Journal of Pharmaceutical and Biomedical Analysis, Volume
84 Author(s): Ka H. Wong , Valentina Razmovski-Naumovski , Kong M. Li ,
George Q. Li , Kelvin Chan The aims of the study were to differentiate
Pueraria lobata from its related species Pueraria thomsonii and to examine the
raw herbal material used in manufacturing kudzu root granules using partial
least square discriminant analysis (PLS-DA). Sixty-four raw materials of P.
lobata and P. thomsonii and kudzu root-labelled granules were analysed by ultra
performance liquid chromatography. To differentiate P. lobata from P. thomsonii,
PLS-DA models using the variables selected from the entire chromatograms,
genetic algorithm (GA), successive projection algorithm (SPA), puerarin alone
and six selected peaks were employed. The models constructed by GA and SPA
demonstrated superior classification ability and lower model's complexity as
compared to the model based on the entire chromatographic matrix, whilst the
model constructed by the six selected peaks was comparable to the entire
chromatographic model. The model established by puerarin alone showed inferior
classification ability. In addition, the PLS-DA models constructed by the entire
chromatographic matrix, GA, SPA and the six selected peaks showed that four
brands out of seventeen granules were mislabelled as P. lobata. In conclusion,
PLS-DA is a promising procedure for differentiating Pueraria species and
determining raw material used in commercial products.
Publication date: October
2013 Source:Journal of Pharmaceutical and Biomedical Analysis, Volume
84 Author(s): Chunlin Fan , Jiewei Deng , Yunyun Yang , Junshan Liu , Ying
Wang , Xiaoqi Zhang , Kuokchiu Fai , Qingwen Zhang , Wencai Ye An
ultra-performance liquid chromatography coupled with quadrupole time-of-flight
mass spectrometry (UPLC–QTOF-MS) method integrating multi-ingredients
determination and fingerprint analysis has been established for quality
assessment and control of leaves from Ilex latifolia. The method possesses the
advantages of speediness, efficiency, accuracy, and allows the multi-ingredients
determination and fingerprint analysis in one chromatographic run within 13min.
Multi-ingredients determination was performed based on the extracted ion
chromatograms of the exact pseudo-molecular ions (with a 0.01Da window), and
fingerprint analysis was performed based on the base peak chromatograms,
obtained by negative-ion electrospray ionization QTOF-MS. The method validation
results demonstrated our developed method possessing desirable specificity,
linearity, precision and accuracy. The method was utilized to analyze 22 I.
latifolia samples from different origins. The quality assessment was achieved by
using both similarity analysis (SA) and principal component analysis (PCA), and
the results from SA were consistent with those from PCA. Our experimental
results demonstrate that the strategy integrated multi-ingredients determination
and fingerprint analysis using UPLC–QTOF-MS technique is a useful approach for
rapid pharmaceutical analysis, with promising prospects for the differentiation
of origin, the determination of authenticity, and the overall quality assessment
of herbal medicines.
Publication date: October
2013 Source:Journal of Pharmaceutical and Biomedical Analysis, Volume
84 Author(s): Ting-Fu Jiang , Ting-Ting Liang , Yuan-Hong Wang , Wen-Hui
Zhang , Zhi-Hua Lv A method for creating an immobilized capillary tyrosinase
(TRS) reactor based on a layer-by-layer (LBL) assembly for inhibitor screening
is described. Tyrosinase was immobilized on the surface of fused-silica
capillary via ionic binding technique with cationic polyelectrolyte
hexadimethrine bromide (HDB). Then, HDB solution with the same plug length as
the TRS was injected again into the capillary to cover the immobilized enzyme by
forming HDB–TRS–HDB sandwich-like structure. Then, the substrate of l-tyrosine
was introduced into the capillary and on-line enzyme inhibition study was
performed by capillary electrophoresis (CE). The enzyme activity was determined
by the quantification of peak area of the product of l-DOPA. Enzyme inhibition
can be read out directly from the reduced peak area of the product in comparison
with a reference electropherogram obtained in the absence of any inhibitor. The
immobilized enzyme could withstand 25 consecutive assays by only losing 12%
activity. A known TRS inhibitor, kojic acid was employed as a model compound for
the validation of the inhibitor screening method. Finally, screening 19 natural
extracts of traditional Chinese drugs was demonstrated. The results indicated
that inhibition activity could be straightforwardly identified with the system.
Publication date: October
2013 Source:Journal of Pharmaceutical and Biomedical Analysis, Volume
84 Author(s): Wen-Jun Zhou , Jing-Zheng Song , Wen-Wei Fu , Hong-Sheng Tan ,
Zhao-Xiang Bian , Hong-Xi Xu Hemp seed soft gel capsule (HSSGC) is a
modernised dosage form that is derived from a traditional Chinese patent
medicine, Hemp Seed Pills (HSP). Two dosage forms claim the same therapeutic
effects; however, their chemical components and chemical equivalency are
unclear. In the present study, an ultra performance liquid chromatography
coupled with time-of-flight mass spectrometry (UHPLC-ToF–MS)-based chemical
profiling approach was proposed to rapidly evaluate the chemical differences
between HSP and HSSGC as model dosage forms. Samples of the two dosage forms
were subjected to UHPLC-ToF–MS analysis. The datasets of retention time (T R)
and mass-to-charge ratio (m/z) pairs, ion intensities and sample codes were
processed with principal component analysis (PCA) and partial least squares
discriminate analysis (PLS-DA) to holistically compare the difference between
these two dosage form samples. A clear classification trend was observed in the
score plot, and a loading bi-plot was generated in which the variables are
correlated with the group and the samples that were observed. The important
chemical components that caused differences among the samples were explored with
a Variables Importance Projection (VIP) index. Using the proposed approach,
global chemical differences were found between the two dosage forms and among
samples of the same dosage form. The most important components that are related
to the differences were identified and most of them were attributed to Fructus
Aurantii Immaturus. It is suggested that this newly established approach could
be used for pre-clinical trial chemical equivalence study or the quality
evaluation of the traditional medicinal products with large variations in
quality.
Publication date: October
2013 Source:Journal of Pharmaceutical and Biomedical Analysis, Volume
84 Author(s): Ming-juan Wang , Ya-Ping Li , Yan Wang , Jin Li , Chang-qin Hu
, Jos Hoogmartens , Ann Van Schepdael , Erwin Adams Reversed-phase liquid
chromatography coupled with photo-diode array (PDA) detection and electrospray
ionization tandem mass spectrometry (ESI-MS/MS) was used to characterize the
components of meleumycin, a 16-membered macrolide antibiotic produced by
fermentation. In total 31 components were characterized in commercial samples,
including 12 impurities that had never been reported before and 12 others that
were partially characterized. The structures of these unknown compounds were
deduced by comparison of their fragmentation patterns with those of known
components. Their ultraviolet spectra and chromatographic behavior were used to
confirm the proposed structures: e.g. λ max shift from 232nm to 282nm would
indicate the presence of an α-, β-, γ-, δ-unsaturated ketone instead of a normal
α-, β-, γ-, δ-unsaturated alcohol in the 16-membered ring of the examined
components. Compared to other methods, this LC/MS n method is
particularly advantageous to characterize minor components at trace levels in
multi-components antibiotics, in terms of sensitivity and efficiency.
Publication date: October
2013 Source:Journal of Pharmaceutical and Biomedical Analysis, Volume
84 Author(s): Federica Pellati , Francesco Pio Prencipe , Stefania
Benvenuti In this study, a novel and efficient method based on headspace
solid-phase microextraction (HS-SPME), followed by gas chromatography–mass
spectrometry (GC–MS), was developed for the analysis of propolis volatile
compounds. The HS-SPME procedure, whose experimental parameters were properly
optimized, was carried out using a 100μm polydimethylsiloxane (PDMS) fiber. The
GC–MS analyses were performed on a HP-5 MS cross-linked 5% diphenyl-95% dimethyl
polysiloxane capillary column (30m×0.25mm I.D., 1.00μm film thickness), under
programmed-temperature elution. Ninety-nine constituents were identified using
this technique in the samples of raw propolis collected from different Italian
regions. The main compounds detected include benzoic acid (0.87–30.13%) and its
esters, such as benzyl benzoate (0.16–13.05%), benzyl salicylate (0.34–1.90%)
and benzyl cinnamate (0.34–3.20%). Vanillin was detected in most of the samples
analyzed in this study (0.07–5.44%). Another relevant class of volatile
constituents is represented by sesquiterpene hydrocarbons, such as δ-cadinene
(1.29–13.31%), γ-cadinene (1.36–8.85%) and α-muurolene (0.78–6.59%), and
oxygenated sesquiterpenes, such as β-eudesmol (2.33–12.83%), T-cadinol
(2.73–9.95%) and α-cadinol (4.84–9.74%). Regarding monoterpene hydrocarbons,
they were found to be present at low level in the samples analyzed in this
study, with the exception of one sample from Southern Italy, where α-pinene was
the most abundant constituent (13.19%). The results obtained by HS-SPME-GC–MS
were also compared with those of hydrodistillation (HD) coupled with GC–MS. The
HS-SPME-GC–MS method developed in this study allowed us to determine the
chemical fingerprint of propolis volatile constituents, thus providing a new and
reliable tool for the complete characterization of this biologically active
apiary product.
Publication date: October
2013 Source:Journal of Pharmaceutical and Biomedical Analysis, Volume
84 Author(s): Ágnes Emma Daruházi , Tímea Kiss , Miklós Vecsernyés , Lajos
Szente , Éva Szőke , Éva Lemberkovics Isoflavonoids are widespread
constituents in medical plants especially in legumes (Fabaceae), but occur in
other different plant families as well (Rosaceae, Iridaceae, Amaranthaceae).
Their antioxidant, estrogen-like, anti-inflammatory and analgesic effects make
them promising compounds in therapy of important disorders especially in
estrogen related diseases. Poor solubility in aqueous system of genistein and
daidzein needs a solubility enhancement for pharmaceutical use. These compounds
are suitable guest molecules for inclusion complex formation with cyclodextrins
(CDs) considering matching their size and polarity. The molecular encapsulation
with beta-cyclodextrin (β-CD), gamma-cyclodextrin (γ-CD),
hydroxypropyl-beta-cyclodextrin (HP-β-CD) and random methyl-beta cyclodextrin
(RAMEB-CD) results in a solid, molecularly dispersed form and in a significantly
improved aqueous solubility of genistein and daidzein. Determining enhancement
in solubility and bioavailability we investigated the transport of these
inclusion complexes across Caco-2 cell line comparing that of the pure compounds
and found significant improving effect of the different CD derivatives on
membrane permeation of the two isoflavone aglycons.
Publication date: October
2013 Source:Journal of Pharmaceutical and Biomedical Analysis, Volume
84 Author(s): István Antal , Nikolett Kállai , Oliver Luhn , Jörg Bernard ,
Zsombor Kristóf Nagy , Barnabás Szabó , Imre Klebovich , Romána Zelkó The
major objective of this study was to disclose the relationships between the
physical quality attributes and supramolecular structure of novel composite
pellet cores containing microcrystalline cellulose (MCC) and isomalt in
different ratios. The novel composite pellet cores were manufactured by an
extrusion/spheronisation process. The micro or supramolecular structure of
pellets was tracked by positron annihilation lifetime spectroscopy (PALS) based
on the o-Ps lifetime values. The results indicate a correlation between the
examined macro and microstructural properties of the inert cores. The higher
free volume holes indicated by the higher o-Ps lifetime values resulted in a
more mobile micro- and supramolecular structure of MCC cores thus increasing the
plastic deformation and the tensile strength of the cores. A physical
interaction was found between the microcrystalline cellulose and isomalt which
supports the osmotic effect of the water soluble sugar alcohol in the composite
pellet cores regarding drug release.
Publication date: October
2013 Source:Journal of Pharmaceutical and Biomedical Analysis, Volume
84 Author(s): Jitka Široká , Daniel N. Polesel , Jose L. Costa , Rafael
Lanaro , Marina F.M. Tavares , Miroslav Polášek A simple capillary
electrophoretic method with spectrophotometric UV detection at 236nm has been
developed for the selective separation and determination of
1-(2-chlorophenyl)piperazine (oCPP), 1-(3-chlorophenyl)piperazine (mCPP) and
1-(4-chlorophenyl)piperazine (pCPP) in confiscated pills. Several cyclodextrin
derivatives were tested to compose the background electrolyte (BGE). The
optimized BGE contained 20mmol/L phosphoric acid adjusted to pH 2.5 with
triethylamine and 10mmol/L α-cyclodextrin, which provided acceptable resolution
of analytes and candidate interferents in less than 15min. The analyses were
performed at constant voltage of 25kV in 60cm (effective length 50cm; 50μm i.d.)
uncoated fused-silica capillary maintained at 25°C with sample injection at
4826Pa for 8s. Procaine at a concentration of 0.1mg/mL was used as internal
standard (IS). Possible interference from other drugs such as amphetamine,
methamphetamine, 3,4-methylenedioxyamphetamine,
3,4-methylenedioxymethamphetamine, 3,4-methylenedioxy-N-ethylamphetamine,
1-(3-trifluoromethylphenyl)piperazine and cocaine was also examined. The
analytical curves were linear (R 2 =0.9994–0.9995) in the range of
10–200μg/mL (for oCPP and mCPP) and 20–200μg/mL for pCPP. Limits of detection
(LODs) were 2.0μg/mL (oCPP), 2.5μg/mL (mCPP) and 3.5μg/mL (pCPP). Intraday
precision at three concentration levels and six replicates of each level (10,
100, 200μg/mL of each analyte; n =18) was evaluated for the corrected peak area
ratio of analyte to IS and the migration times giving RSDs≤4.9%. The accuracy
was estimated for mCPP by a recovery test at the same three concentration levels
and recoveries varied from 101.0 to 101.6%. The method has been successively
applied to the analysis of 17 confiscated pills based mostly on mCPP.
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