Capillary Electrophoresis Fingerprints Research Articles

Rapid quality assessment of Gentianae Macrophyllae Radix based on near infrared spectroscopy and capillary electrophoresis.

The aim of this study was to establish a rapid quality assessment method for Gentianae Macrophyllae Radix (RGM) using near infrared (NIR) spectra combined with chemometric analysis. The NIR spectra were acquired using an integrating sphere diffuse reflectance module, using air as the reference. Capillary electrophoresis (CE) analyses were performed on a model P/ACE MDQ Plus system. Partial least squares-discriminant analysis qualitative model was developed to distinguish different species of RGM samples, and the prediction accuracy for all samples was 91%. The CE response values at each retention time were predicted by building a partial least squares regression (PLSR) calibration model with the CE data set as the Y matrix and the NIR spectra data set as the X matrix. The converted CE fingerprints basically match the real ones, and the six main peaks can be accurately predicted. Transforming NIR spectra fingerprints into the form of CE fingerprints increases its interpretability and more intuitively demonstrates the components that cause diversity among samples of different species and origins. Loganic acid, gentiopicroside and roburic acid were considered as quality indicators of RGM and calibration models were built using PLSR algorithm. The developed models gave root mean square error of prediction of 0.2592% for loganic acid, 0.5341% for gentiopicroside and 0.0846% for roburic acid. The overall results demonstrate that the rapid quality assessment system can be used for quality control of RGM. This article is protected by copyright. All rights reserved.

Fluorescence labeled capillary electrophoresis fingerprint analysis of sulfonamides residues in tea garden soil and tea

A fluorescence labeled capillary electrophoresis fingerprint method for the analysis of sulfonamides residues in tea garden soil and tea was established by using o-phthalaldehyde (OPA) as precolumn derivatization reagent. The effects of background electrolyte concentration, pH, column temperature and voltage on the separation conditions were investigated. The optimum separation conditions were as follows: Glycine sodium hydroxide slow concentration: 20 mmol/L; pH: 9.0; Column temperature: 20 °C; Separation voltage: 17 kv, pressure: 50 mbar, injection time: 8 s. Under the established optimal conditions, 13 sulfonamide derivatives could be separated efficiently within 9 min, and the linear range is 0.35~100μg/kg, the detection limit (signal-to-noise ratio is 3) is in the range of 0.12-0.25 μg/kg, the quantitative limit (signal-to-noise ratio is 10) is in the range of 0.35-0.70μg/kg.

Holistic quality evaluation of compound liquorice tablets using capillary electrophoresis fingerprinting combined with chemometric methods

Integrated quality control of herbal medicine using eco-friendly capillary zone electrophoresis and equal weight ratio quantitative fingerprint method.

The evaluation of the chemical quality and UV overall components dissolution consistency of Flos Chrysanthemi Indici preparation.

In recent years, new chemical technology and chemical analysis methods have been widely used for the quality control of medicine to provide security for human life. However, for the increasingly popular traditional Chinese medicine (TCM) preparations, the traditional quality control technology has been challenged due the presence of multi-components. To solve this problem, this study proposed a comprehensive evaluation strategy from two aspects: chemical quality and in vitro dissolution consistency. Zhenju antihypertensive tablet (FCIP), as the research object of this study, is a compound preparation of Flos Chrysanthemi Indici with moderate antihypertensive effect. For the chemical quality, the capillary electrophoresis fingerprint (CE-FP) was established based on the characteristic multi-wavelength averaging fusion profiling (CMW-AFP) strategy, which can fuse peaks in the CE chromatogram at several select characteristic wavelengths into one profile through an averaging algorithm. All samples were clarified into 5 quality grades using the systematic quantified fingerprint method, and showed significant difference among the four manufacturers. Combined with the accurate determination of the marker components, the CE-FP evaluation results can provide a guarantee for the chemical quality consistency. For the in vitro dissolution consistency, a UV overall components dissolution method was proposed. Meanwhile, in order to match the established UV overall dissolution system, two f2 factors (f2-R and f2-MI) were calculated to compare the dissolution profiles. By comparing the chemical and UV overall dissolution results plus the PCA analysis, the holistic quality of the FCIP samples of four manufacturers were obtained as MA > MC > MD > MB. The established evaluation system is also a suitable strategy for controlling the chemical quality and dissolution consistency of other TCM preparations.

Capillary electrophoresis fingerprints combined with Linear Quantitative Profiling Method to monitor the quality consistency and predict the antioxidant activity of Alkaloids of Sophora flavescens

Alkaloids of Sophora flavescens (ASF) has various pharmacological effects, and it is widely used in clinical practice. The aim of this research was to develop an environmentally friendly methodology that enables not only identification but also the quality consistency assessment of Alkaloids of Sophora flavescens. A background electrolyte composed of 50 mmol/L sodium tetraborate solution, 500 mmol/L boric acid and 1.2 mmol/L citric acid was used to conduct the fingerprint analysis coupled with quantitative determination of three components. Linear quantitative profiling method was used for comprehensive quality discrimination of the test samples from both qualitative and quantitative perspectives, and the 27 batches of samples were well differentiated. In addition, the fingerprint-efficacy relationship between chemical components and antioxidant activity in vitro was established using partial least squares regression model, which provided important medicinal efficacy information for quality control.

Capillary electrophoresis fingerprints combined with chemometric methods to evaluate the quality consistency and predict the antioxidant activity of Yinqiaojiedu tablet.

The quality consistency of Yinqiaojiedu tablets (YQJDTs) was monitored by extracting their electrophoretic fingerprint and marker compound data that were obtained using capillary electrophoresis. To select the suitable background electrolyte, wing-shape method was proposed. A background electrolyte composed of 103.1mM boric acid, 51.6mM sodium borate, 9.8mM disodium hydrogenphosphate, and 15.6mM sodium dihydrogen phosphate was used to separate compounds. Under the optimized conditions, the content of three marker compounds was determined in 25 YQJDT samples. The capillary electrophoresis fingerprints were developed simultaneously, then 25 samples from two manufacturers were clearly divided into two clusters based on the principal component analysis. In fingerprint assessments, systematic quantified fingerprint method was adopted for integrative quality discrimination of YQJDTs from both qualitative and quantitative perspectives, by which the qualities of 25 samples were well differentiated. In addition, partial least squares model was established to explore fingerprint-efficacy relationship between the fingerprints and the antioxidant activities in vitro, providing clinically useful information for quality control. The proposed method was reliable and comprehensive, which could be used for a valuable reference to monitor the quality consistency of traditional Chinese medicines.

Capillary electrophoresis fingerprinting and spectrophotometric determination of antioxidant potential for classification of Mentha products.

In this work aqueous infusions from ten Mentha herbal samples (four different Mentha species and six hybrids of Mentha x piperita) and 20 different peppermint teas were screened by capillary electrophoresis with UV detection. The fingerprint separation was accomplished in a 25 mM borate background electrolyte with 10% methanol at pH 9.3. The total polyphenolic content in the extracts was determined spectrophotometrically at 765 nm by a Folin-Ciocalteu phenol assay. Total antioxidant activity was determined by scavenging of 2,2-diphenyl-1-picrylhydrazyl radical at 515 nm. The peak areas of 12 dominant peaks from CE analysis, present in all samples, and the value of total polyphenolic content and total antioxidant activity obtained by spectrophotometry was combined into a single data matrix and principal component analysis was applied. The obtained principal component analysis model resulted in distinct clusters of Mentha and peppermint tea samples distinguishing the samples according to their potential protective antioxidant effect. Principal component analysis, using a non-targeted approach with no need for compound identification, was found as a new promising tool for the screening of herbal tea products.

Capillary electrophoresis fingerprinting of 8-aminopyrene-1,3,6-trisulfonate derivatized nitrocellulose after partial acid depolymerization

Fine characterization of nitrocellulose (NC) remains a challenge, especially in forensic analysis, and a strategy consisting in obtaining representative fingerprints by a separation technique, as for proteins, is of prime interest. In this work, we first established that NCs (especially of high molar mass) cannot be representatively derivatized by 8-aminopyrene-1,3,6-trisulfonic acid (APTS), because of their poor solubility in the medium required for APTS derivatization. Therefore, a partial acid depolymerization step was considered, prior to derivatization by APTS, in an attempt to generate a mixture of oligosaccharides retaining information on the initial NC sample and/or on the cellulose used to prepare it. Acid depolymerization conditions (time and acid concentration) as well as APTS derivatization conditions (time, temperature, APTS/NC and reducing agent/APTS molar ratios) were investigated for lowly-nitrated NCs. The best compromise between depolymerization yields, speed, and pertinency of the resulting oligosaccharidic mixture was obtained using fuming hydrochloric acid (37%, w/w) at 50°C for 30min. The most effective procedure for APTS derivatization of oligosaccharides obtained after partial acid depolymerization of NC was achieved at 70°C for 2h. The resulting APTS-derivatized oligosaccharides were then separated by capillary electrophoresis (CE) using a background electrolyte composed of 60mM 6-aminocaproic acid, pH 4.5 (adjusted with acetic acid)+0.02% hydroxypropyl methyl cellulose. Finally, for the first time, they were identified using APTS-derivatized cellodextrin standards and by matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS).

Capillary electrophoresis fingerprints of Baizi Yangxin Wan

The capillary electrophoresis fingerprint (CEFP) of Baizi Yangxin Wan (BZYXW) was established by capillary zone electrophoresis (CZE). The chromatographic fingerprint resolution index (RF) was applied to optimize the CEFP conditions. The electrophoretic separation was performed on a 75 cm (the effective length of 57 cm) x 75 microm uncoated fused silica capillary with 50 mmol/L sodium borate-50 mmol/L Na2HPO(4)-200 mmol/L H3BO(3)-150 mmol/L NaHCO3 (7:7:1:1, v/v/v/v) containing 4% acetonitrile (pH 9.70) as the background electrolyte (BGE), and the BGE was chosen by using the triangular prism optimization method. The running voltage was set at 12 kV, and the detection wavelength at 228 nm. The sample solution was injected into the capillary by hydraulic pressure in 25 s. The CEFPs were produced by the electropherograms from 12 batches of BZYXW, and the 17 co-possessing peaks were selected as the fingerprint peaks of BZYXW's CEFP by choosing ferulic acid peak as the referential peak. According to the results of classification, the reference CEFP (RCEFP) was synthesized from 12 batches of BZYXW. Taking the RCEFP for the qualified model, the systematically quantified fingerprint method(SQFM) was applied to evaluate the quality of 17 batches of BZYXW, in which the qualities of 3 batches was evaluated as good, 1 batch as fine, 3 batches as moderate, 1 batch as common, and 4 batches as inferior. The triangular prism optimization method was suggested to be good to optimize the BGE. The results showed that the BZYXW-CEFP was established with good precision and reproducibility, which can be served as a novel reference to identify and control the quality of BZYXW.

PSP activates monocytes in resting human peripheral blood mononuclear cells: Immunomodulatory implications for cancer treatment

Polysaccharopeptide (PSP), from Coriolus versicolor, has been used as an adjuvant to chemotherapy, and has demonstrated anti-tumor and immunomodulating effects. However its mechanism remains unknown. To elucidate how PSP affects immune populations, we compared PSP treatments both with and without prior incubation in phytohaemagglutinin (PHA) – a process commonly used in immune population experimentation. We first standardised a capillary electrophoresis fingerprinting technique for PSP identification and characterisation. We then established the proliferative capability of PSP on various immune populations in peripheral blood mononuclear cells, using flow cytometry, without prior PHA treatment. It was found that PSP significantly increased the number of monocytes (CD14+/CD16−) compared to controls without PHA. This increase in monocytes was confirmed using another antibody panel of CD14 and MHCII. In contrast, proliferations of T-cells, NK, and B-cells were not significantly changed by PSP. Thus, stimulating monocyte/macrophage function with PSP could be an effective therapeutic intervention in targeting tumors.

Capillary electrophoresis finger print technique (CE-SSCP): an alternative tool for the monitoring activities of HAB species in Baja California Sur Costal

In Mexican waters, there is no a formal and well-established monitoring program of harmful algal blooms (HAB) events. Until now, most of the work has been focused on the characterization of organisms present in certain communities. Therefore, the development of new techniques for the rapid detection of HAB species is necessary. Capillary electrophoresis finger print technique (CE-SSCP) is a fingerprinting technique based on the identification of different conformers dependent of its base composition. This technique, coupled with capillary electrophoresis, has been used to compare and identify different conformers. The aim of this study was to determine if CE-SSCP analysis of ribosomal RNA (rRNA) gene fragments could be used for a rapid identification of toxic and harmful HAB species to improve monitoring activities along the coasts of Baja California Sur, Mexico.Three different highly variable regions of the 18S and 28S rRNA genes were chosen and their suitability for the discrimination of different dinoflagellate species was assessed by CE-SSCP.The CE-SSCP results obtained for the LSU D7 fragment has demonstrated that this technique with this gene region could be useful for the identification of the ten dinoflagellates species of different genera.We have shown that this method can be used to discriminate species and the next step will be to apply it to natural samples to achieve our goal of molecular monitoring for toxic algae in Mexican waters. This strategy will offer an option to improve an early warning system of HAB events for coastal BCS, allowing the possible implementation of mitigation strategies. A monitoring program of HAB species using molecular methods will permit the analysis of several samples in a short period of time, without the pressure of counting with a taxonomic expert in phytoplankton taxonomy.

Development of capillary electrophoresis fingerprint for quality control of Rhizoma Smilacis Glabrae

Rhizoma Smilacis Glabrae (RSG) is a Chinese herbal medicine used for detoxication and as a diuretic. However, in some regions of China, RSG is used confusedly with some other herbs. To develop a capillary electrophoresis (CE)-DAD fingerprint method for quality evaluation, species differentiation and product identification of RSG. The CE separation conditions and extraction procedure were optimised. Eighteen batches of RSG samples were analysed and the standard fingerprint used for authentication was simulated by the average of all tested samples. The optimal CE separation conditions were developed with running buffer of 20 mm borax containing 3 mm β-cyclodextrin at pH 9.4, voltage of 25 kV and temperature of 25°C. The separation could be completed within 8 min. Nine peaks were found in the electropherogram of RSG and five peaks were identified as astilbin, taxifolin, 5-O-caffeoylshikimic acid, shikimic acid and trans-resveratrol, respectively. Methanol and sonication were recommended for the sample preparation. All RSG samples showed similar chromatographic profile and six 'held in common' peaks were found. By the standard fingerprint, RSG could be well distinguished from its two confusable species, rhizoma Smilacis Chinae and rhizoma Heterosmilacis. A CE-DAD fingerprint analysis method was developed for the quality control of RSG. The standard fingerprint could represent the chemical profile of RSG and be used for its authentication.

Bidirectional Correlation of NMR and Capillary Electrophoresis Fingerprints: A New Approach to Investigating Schistosoma mansoni Infection in a Mouse Model

We demonstrate the statistical integration of nuclear magnetic resonance (NMR) spectroscopy and capillary electrophoresis (CE) data in order to describe a pathological state caused by Schistosoma mansoni infection in a mouse model based on urinary metabolite profiles. Urine samples from mice 53 days post infection with S. mansoni and matched controls were analyzed via NMR spectroscopy and CE. The two sets of metabolic profiles were first processed and analyzed independently and were subsequently integrated using statistical correlation methods in order to facilitate cross assignment of metabolites. Using this approach, metabolites such as 3-ureidopropionate, p-cresol glucuronide, phenylacetylglycine, indoxyl sulfate, isocitrate, and trimethylamine were identified as differentiating between infected and control animals. These correlation analyses facilitated structural elucidation using the identification power of one technique to enhance and validate the other, but also highlighted the enhanced ability to detect functional correlations between metabolites, thereby providing potential for achieving deeper mechanistic insight into the biological process.

Identification and classification of Dendrobium candidum species by fingerprint technology with capillary electrophoresis

A capillary electrophoresis fingerprint method was established to evaluate the quality of Dendrobium candidum. The method of sample preparation and the electrophoresis condition were optimized to obtain highly sensitive and specific capillary electropherogram. The analysis was performed on a fused-silica capillary (65 cm×75 µm i.d). The detection wavelength was 195 nm and a voltage of 20 kV was applied. The background electrolyte was a 40 mmol/L sodium borate solution (5% methanol, v/v) adjusted to pH 9.5 with 0.1 mmol/L NaOH solution. Medicinal materials were extracted by ethanol reflux for 2 h. The capillary electrophoresis fingerprints of 69-sample of Dendrobium candidum species from 10 different areas showed 15 characteristic peaks which could be applied to identification of this species. The coefficients were from 0.854 to 0.963 between standard fingerprint and each sample. The quantitative data of the fingerprints were analyzed by principal component analysis (PCO), UPGMA cluster analysis and the results showed that samples from different regions could be divided into three groups. Moreover, a rapid and convenient discriminant function was established to classify the Dendrobium candidum plants. The data revealed that the coincidence rate of all samples attached 100% by this discriminant model. The method is reliable and could be used to control the quality of medicinal plants including Dendrobium candidum species in the future.

Capillary electrophoresis fingerprinting, quantification and mass-identification of various 9-aminopyrene-1,4,6-trisulfonate-derivatized oligomers derived from plant polysaccharides

Various plant polysaccharide derived mono- and oligosaccharides were derivatized with the fluorescent 9-aminopyrene-1,4,6-trisulfonate (APTS) and subjected to capillary electrophoresis (CE) in combination with laser induced fluorescence (LIF) detection. CE-LIF was suitable for mol-based quantification of various APTS-monosaccharides. CE-LIF of APTS-oligosaccharides showed high resolutions, while analysis times were at maximum 15 min. The coupling of CE to electrospray-iontrap mass spectrometery (MS) with online UV detection showed to be a powerful technique in the identification of APTS-oligosaccharides. For the first time, various APTS-xylo-oligosaccharides, having either no, O-acetyl, arabinosyl or xylosyl substitutions at varying positions, were identified by using CE-LIF and CE-MS n .

Quantitative analysis and chromatographic fingerprinting for the quality evaluation of Scutellaria baicalensis Georgi using capillary electrophoresis

Quantitative analysis and chromatographic fingerprinting for the quality evaluation of a Chinese herb Scutellaria baicalensis Georgi using capillary electrophoresis (CE) technique was developed. The separation was performed with a 50.0 cm (42.0 cm to the detector window) × 75 μm i.d. fused-silica capillary, and the CE fingerprint condition was optimized using the combination of central composite design and multivariate analysis. The optimized buffer system containing 15 mM borate, 40 mM phosphate, 15 mM SDS, 15% (v/v) acetonitrile and 7.5% (v/v) 2-propanol was employed for the method development, and the baseline separation was achieved within 15 min. The determination of the major active components (Baicalin, Baicalein and Wogonin) was carried out using the optimized CE condition. Good linear relationships were provided over the investigated concentration ranges (the values of R 2: 0.9997 for Baicalin, 0.9992 for Baicalein, and 0.9983 for Wogonin, respectively). The average recoveries of these target components ranged between 96.1–105.6%, 98.6–105.2%, and 96.3–105.0%, respectively. CE fingerprints combined with the quantitative analysis can be used for the quality evaluation of S. baicalensis.

Analysis of polyphenols in wines: Correlation between total polyphenolic content and antioxidant potential from photometric measurements: Prediction of cultivars and vintage from capillary zone electrophoresis fingerprints using artificial neural network

The polyphenols (some of them are also called phytoalexins, flavonols, flavanons, flavanonols, flavons, flavanols, and anthocyanines) are usually marked as potent antioxidants or radical scavengers which assist the body cells against oxidation. Polyphenols in wine are also considered to explain so called French paradox (long life aging and low number of coronary diseases despite of high alcohol and fat consumption). The total polyphenolic content (TPC) and total antioxidant potential (TAP) were determined by photometry and found strongly correlated. This finding suggests that the determination of TAP can be replaced by a more simple procedure of TPC determination. Capillary zone electrophoresis (CZE) with preconcentration by solid phase extraction (SPE) was applied for some polyphenols determination and for obtaining electropherograms of the SPE extracts (fingerprints). From mathematical evaluation of the fingerprints, prediction of cultivars and vintage using artificial neural networks (ANN) was done with more than 90% correct prediction. The study was performed on a set of 47 samples of young wines (vintage 1999–2002) from south Moravia (Czech Republic) and New South Wales (Australia).

On-column labeling reaction for analysis of protein contents of a single cell using capillary electrophoresis with laser-induced fluorescence detection.

This chapter presents methods for capillary electrophoresis (CE) fingerprinting of proteins in a cell extract and in single cells. A custom-made CE instrument with laser-induced fluorescence (LIF) detection, used for the analyses, is described. Detailed procedures are given for: (1) on column labeling of proteins with a fluorogenic reagent, 5-furoyl quinoline-3-carboxaldehyde, (2) CE separation of labeled proteins, (3) preparation of a protein extract from cultured cells, and (4) manipulations associated with analyses of proteins in single cells. More than 20 relevant publications are cited in this chapter to assist the reader with adopting the presented methods.

The quality assessment of compound liquorice tablets by capillary electrophoresis fingerprints.

Capillary electrophoresis (CE) is a powerful separation technique that is peculiarly able to determine the fingerprints of traditional Chinese medicine. The Capillary Electrophoresis Fingerprints (CEFP) of compound liquorice tablets (CLTs) was established to evaluate the quality of CLTs. The background electrolyte was a 50 mM sodium borate solution. The detection wavelength was 228 nm and a 14 kV voltage was applied. Hydrochlorothiazide served as an internal standard and temperature was 24-25 degrees C. The CLTs were extracted by a 50 mM borate solution containing 10% (v/v) methanol. The results showed that CE was a powerful tool for detecting of the fingerprints of traditional Chinese medicine and their constituents. The quality assessments were performed to compare the correlation coefficients (R) and cos theta (C) between each batch vector of CLTs and the total standard profile vector (TSPV), which was the mean vector of all the batch vectors of CLTs with 1.0. The nearer to 1.0 was the R or C, the higher was the similarity. The values of R and C between the TSPV and each batch vector of CLTs produced at different factories were all above 0.9150. The values of R and C between every two standard profile vectors (SPV) from different factories were all above 0.9420. A good stability and reproducibility of the CEFP of CLTs were obtained in the study. Further, we first put forward a new parameter Q to evaluate both the quantification accuracy and the qualitative accuracy for a CEFP, which was verified by determinations of GHIA, GHEA, MP and SB in CLTs. The CEFP was successfully employed to assess the quality of CLTs produced at Kunming Pharmaceutical Factory to be good.

Identification of proteins in single-cell capillary electrophoresis fingerprints based on comigration with standard proteins.

In the previous paper in this Journal, we reported the use of capillary sieving electrophoresis to characterize proteins expressed by single cancer cells at specific phases in the cell cycle. Analysis of the data revealed one component with cell cycle-dependent changes in expression at the 99% confidence limit. However, the amount of protein present in a single cell is far too small to allow its direct identification by mass spectrometry. In this paper, we report a method by which such proteins can be tentatively identified. We perform standard SDS-PAGE electrophoresis of the proteins contained within a homogenate prepared from an HT29 cell culture. Proteins extracted from bands in the gel are identified by mass spectrometry. The proteins also provide a set of standards that can be used to spike the sample before capillary sieving electrophoresis (CSE) separation; comigration is taken as evidence for the identity of the target protein. In a proof-of-principle experiment, a single band migrating at approximately 47 kDa was isolated from the SDS-PAGE gel generated from the HT29 cell line. Proteins extracted from this band were used to spike a CSE separation of the same extract. This band comigrated with a cell cycle-dependent component identified from single-cell analysis. In-gel digestion and LC/MS/MS were used to identify five proteins, including cytokeratin 18, which is the product of the most highly expressed gene in this cell line.