Multicomponent Analysis Method Research Articles

Empirical Modal Decomposition Combined with Deep Learning for Photoacoustic Spectroscopy Detection of Mixture Gas Concentrations.

In photoacoustic spectroscopy based multicomponent gas analysis, the overlap of the absorption spectra among different gases can affect the measurement accuracy of gas concentrations. We report a multicomponent gas analysis method based on empirical modal decomposition (EMD), convolutional neural networks (CNN), and long short-term memory (LSTM) networks that can extract the exact concentrations of mixed gases from the overlapping wavelength-modulated spectroscopy with second harmonic (WMS-2f) detection. The WMS-2f signals of 25 different concentration combinations of acetylene-ammonia mixtures are detected using a single distributed feedback laser (DFB) at 1531.5 nm. The acetylene concentrations range from 2.5 to 7.5 ppm and the ammonia concentrations from 12.5 to 37.5 ppm. The data set is enhanced by cyclic shifting and adding Gaussian noise. The classification accuracy of the test set reaches 99.89% after tuning. The mean absolute errors of the five additional sets of data measured under different conditions are 0.092 ppm for acetylene and 1.902 ppm for ammonia, within the above concentration ranges.

Assessing the ecological impacts of polycyclic aromatic hydrocarbons petroleum pollutants using a network toxicity model

Polycyclic aromatic hydrocarbons (PAHs) are significant petroleum pollutants that have long-term impacts on human health and ecosystems. However, assessing their toxicity presents challenges due to factors such as cost, time, and the need for comprehensive multi-component analysis methods. In this study, we utilized network toxicity models, enrichment analysis, and molecular docking to analyze the toxicity mechanisms of PAHs at different levels: compounds, target genes, pathways, and species. Additionally, we used the maximum acceptable concentration (MAC) value and risk quotient (RQ) as an indicator for the potential ecological risk assessment of PAHs. The results showed that higher molecular weight PAHs had increased lipophilicity and higher toxicity. Benzo[a]pyrene and Fluoranthene were identified as core compounds, which increased the risk of cancer by affecting core target genes such as CCND1 in the human body, thereby influencing signal transduction and the immune system. In terms of biological species, PAHs had a greater toxic impact on aquatic organisms compared to terrestrial organisms. High molecular weight PAHs had lower effective concentrations on biological species, and the ecological risk was higher in the Yellow River Delta region. This research highlights the potential application of network toxicity models in understanding the toxicity mechanisms and species toxicity of PAHs and provides valuable insights for monitoring, prevention, and ecological risk assessment of these pollutants.

Support Vector Models-Based Quantitative Structure–Retention Relationship (QSRR) in the Development and Validation of RP-HPLC Method for Multi-component Analysis of Anti-diabetic Drugs

Support Vector Models-Based Quantitative Structure–Retention Relationship (QSRR) in the Development and Validation of RP-HPLC Method for Multi-component Analysis of Anti-diabetic Drugs

Validated Analytical Method for Multicomponent Analysis of Famotidine and Ofloxacin in Bulk drug and Tablet Formulation by using UV-Visible Spectrophotometer and RP-HPLC

A simple, sensitive, accurate, precise, and reproducible UV- spectrophotometric method and RP-HPLC methods were developed and validated for the estimation of Famotidine and Ofloxacin in bulk drug and pharmaceutical formulation. The Linearity regression was detected and shows a good linear relationship; in the concentration range of 10-50µg/mL (R2 >0.9908) for famotidine and 10-50µg/mL (r2>0.9913) for ofloxacin. The UV – spectrophotometric estimation was carried out by the first-order derivative spectrophotometric method and absorbance were recorded at 273 and 280nm. Beers range were found to be 5-50µg/mL, respectively for both drugs while, correlation coefficient r2 > 0.9988 and 0.9941 for famotidine and ofloxacin. The isoabsorptive point was found to be 274nm in HPLC optimized mobile phase composition, potassium dihydrogen orthophosphate: methanol (60:40). Chromatographic condition consisted of mobile phase potassium dihydrogen orthophosphate buffer pH 2.3, methanol (60:40v/v), run time 30 min, C-18 column (ODS Hypersil) and flow rate 0.8mL/minute. The retention time for famotidine and ofloxacin were found to be 2.44 min, 7.99 min. respectively, and detection at λmax 274nm for both drugs (overlain spectra). The UV methods and RP-HPLC showed good reproducibility and recovery with the percent relative standard deviation (RSD) less than 5%. As per ICH guidelines, the developed method was validated for linearity, accuracy, precision, Sandell's sensitivity, and repeatability proving its utility in the estimation of famotidine and ofloxacin in house tablet formulation.

Direct Cu, Fe, and Ni Ions Multicomponent Analysis Using UV-Vis Spectrophotometric Method

This study presents a direct multicomponent analysis method using UV-Vis spectrophotometry to determine Cu(II), Fe(III), and Ni(II) ion content without prior complexation or separation. Single and multivariate regression was used to predict metal ion content, and the resulting model was trained and validated using a dataset of 25 multi-component samples. The mean recoveries for Cu(II), Fe(III), and Ni(II) using linear and ridge regression based only on absorbance at 805 nm were 99.97% and 101.6%, 95.42% and 95.65%, and 99.43% and 99.99%, respectively, for the 20% test data. The mean recoveries for Cu(II), Fe(III), and Ni(II) using linear and ridge regression based only on absorbance at 805 nm were 92.27% and 95.03%, 125.3% and 124.11%, and 104.15% and 105.52%, respectively, for the test solution outside of the training data. These results demonstrate the effectiveness of the multivariate UV-Vis spectrophotometric method for the simultaneous determination of Cu(II) and Ni(II) in multicomponent samples, which meets the analysis standard and can be successfully applied. Finally, the study sheds light on the influence of spectral interference on the accuracy of regression models. It highlights the importance of carefully selecting the wavelengths used as predictors in such models. This can have significant implications for developing and validating analytical methods, particularly in cases where multiple analytes were present in a sample.

Ultra-High-Performance Liquid Chromatography Quadrupole Time-of-Flight Mass Spectrometry for Simultaneous Pesticide Analysis and Method Validation in Sweet Pepper.

Pesticides effectively reduce the population of various pests that harm crops and increase productivity, but leave residues that adversely affect health and the environment. Here, a simultaneous multicomponent analysis method based on ultra-high-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS) pretreated by the QuEChERS method was developed to control the maximum residual levels. Among the 140 pesticides with high frequency of detection in agricultural products in Gyeongnam region in Korea for 5 years, 12 pesticides with high detection frequency in sweet pepper were selected. The analytical method is validated, linearities are r2 > 0.999, limit of detection (LOD) ranges from 1.4 to 3.2 µg/kg, and limit of quantification (LOQ) ranges from 4.1 to 9.7 µg/kg, and the recovery rate was 81.7-99.7%. In addition, it was confirmed that a meaningful value of these parameters can be achieved by determining the measurement uncertainty. The results proved that parameters such as recovery rate and relative standard deviation of the analysis method were within international standards. Using the developed method, better and safer sweet peppers will be provided to consumers, and effective pesticide residue management will be possible by expanding to other agricultural products.

A liquid chromatography-tandem mass spectrometry method for simultaneous quantification of thirty-nine tyrosine kinase inhibitors in human plasma

Currently, the use of targeted drugs such as tyrosine kinase inhibitors (TKIs) plays an important role in clinical therapy. As the number of approved TKIs continues to increase, existing analysis methods will not be able to meet the growing needs, and will hamper the development of therapeutic drug monitoring (TDM) of TKIs. Based on LC-MS/MS technology, this study tends to develop and validate a multi-component analysis method for simultaneous determination of the concentrations of 39 TKIs in plasma. Spiked plasma was blended with isotope labelled internal standards, and injected into the LC-MS/MS system after protein precipitation by acetonitrile. Chromatographic separation was achieved using an ODS-4 column with gradient elution of formic acid/water (1:1000; v/v) and acetonitrile. Analytes detection was conducted in positive ionisation mode using MRM. The total run time was 8 min. The method validation was conducted by assessing the following parameters: selectivity, linearity and the lower limit of qualification, accuracy and precision, stability, matrix effect and recovery. The concentrations of 39 TKIs showed good linearity within the range of their respective standard curves in plasma, the accuracy of all quality control samples ranged from 85.9% to 114.1%, and the precision was lower than 13.3%. The extraction recovery ranged from 92.6% to 114.7%, and the matrix effect of plasma was lower than 11.3%. This new method was successfully developed, can be used for the determination of drug concentrations in multiple patients with different kinds of TKIs, and will therefore be suitable for TDM of 39 TKIs.

Monitoring the financial security of the Ukrainian banking sector in the context of system-deterministic challenges

The development of the financial market and the transformation of the banking sector create a need for diagnostics of its financial security. This study is aimed at determining the level of the Ukrainian banking sector financial security in the event of decapitalization of the national economy. The paper uses multicomponent and behavioral analysis methods. The empirical study is based on Ukrainian data for 37 indicators by three components (for multicomponent analysis) and 23 indicators (for behavioral analysis). The study presents an improved algorithm for monitoring the level of Ukrainian banking sector’s financial security based on the calculation of the integral indicator. Only the system of “Financial results” indicators as the most significant component has relative independence from the other two components (“Financial stability” and “Macroeconomic stability”). According to assessments, in 2008–2017 Ukrainian banking sector’s financial security was 0,485-0,539; and in 2018 it became 0,626. The behavioral analysis of the partial integral indicator of the “Financial stability” component with the withdrawn assets located in offshore jurisdictions revealed the causal relation of the negative impact of capital outflow on the financial stability of the banking sector. This study has a practical value for determining the level of the banking sector financial security.

СЕНСИБІЛІЗАЦІЯ ДО АЛЕРГОКОМПОНЕНТІВ КЛІЩІВ ДОМАШНЬОГО ПИЛУ У ДІТЕЙ З БРОНХІАЛЬНОЮ АСТМОЮ В УКРАЇНІ

SENSITIZATION TO ALLERGENIC COMPONENTS OF HOUSE DUST MITES IN CHILDREN WITH BRONCHIAL ASTHMA IN KHARKIV REGION V. A. Klymenko1 , T. V. Kulik1 , V. M. Belous2 , O. V. Pyontkovskaya3 , O. M. Savvo3 1 Kharkiv National Medical University, Kharkiv, Ukraine 2 Ecomed Medical Center, Kharkiv, Ukraine 3 Municipal non-profit enterprise of Kharkiv Regional Council «Regional Children’s Clinical Hospital G1», Kharkiv, Ukraine Abstract. The aim of the work is to determine the molecular profile of sensitization to house dust mites in children with bronchial asthma in the Kharkiv region. Object and methods of study. 42 children aged from 6 to 18 years were under observation. Evaluation of the sensitization profile was performed by the method of multicomponent photometric analysis ALEX. Results and discussion. Boys predominated among the patients — 76 %. Patients had intermittent (46 %), mild persistent (31 %), moderate persistent (15 %) and severe persistent asthma (8 %). Allergic rhinitis was noted in 88 % of patients. Elevated IgE levels were observed in 69 % of patients. The median IgE is 385.50 [122.75; 991.00] kU/L. Sensitization to house dust mites was detected in 23 (54 %) patients, of which monosensitization — 10 %; co-sensitization with other aeroallergens — 44 %. Among pediatric patients in the Kharkiv region, the leading sensitization is sensitization to D. farinae (44 %) and D. pteronyssinus (48 %). Molecular sensitization profile: Der f1 — 38.1 %; Der f2 — 38.1 %; Der p1 — 33.33 %; Der p2 — 38.1 %; Der p5 — 14.29 %; Der p7 — 16.67 %; Der p10 — 9.52 %; Der p20 — 2.38 %; Der p23 — 26.19 %. Only minor components (Der p5, 7, 10, 20 or 21) were found in 7.14 % of patients, which proves the need for molecular diagnosis when prescribing immunotherapy. Among the «new» allergens for our region — Blomia tropicalis — sensitizationin 11.9 %; molecular profile: Blo t1 — 2.38 %; Blot 10 — 9.52 %; Blo t21 — 4.76 %. Isolated cases of sensitization to ticks Glycyphagus domesticus, Tyrophagus putrescentiae, Lepidoglyphus destructor have been identified. Conclusions. Differences in sensitization to molecular components of house dust mites in children of the Kharkiv region were proved . It should be taken into account in the diagnosis and treatment of patients with allergic diseases. Key words: bronchial asthma, sensitization, house dust mites, molecular components.

LC-MS/MS and GC-MS/MS cross-checking analysis method for 247 pesticide residues in sweet pepper (Capsicum annuum)

ABSTRACT A simultaneous analysis method using LC-MS/MS and GC-MS/MS was developed for improving the analysis accuracy of various pesticide residues. Samples spiked with 247 and 34 pesticide residues were analyzed by LC-MS/MS and GC-MS/MS, respectively. The method was verified by measuring sensitivity, linearity, selectivity, precision, and accuracy. LC-MS/MS LOD and LOQ values were determined to be 0.03–0.5 μg/kg, and 0.6–1.5 μg/kg, respectively, while the corresponding values for GC-MS/MS were found to be 0.9–2.0 μg/kg and from 3.0–5.7 μg/kg, respectively. Most of the 34 common residues had recovery rates of 70–120%. The results showed that the developed method can be a reliable and more accurate than the general multi component analysis method.

Microorganism@UiO-66-NH2 Composites for the Detection of Multiple Colorectal Cancer-Related microRNAs with Flow Cytometry.

High-throughput analyses of multitarget markers can facilitate rapid and accurate clinical diagnosis. Suspension array assays, a flow cytometry-based analysis technology, are among some of the most promising multicomponent analysis methods for clinical diagnostics and research purposes. These assays are appropriate for examining low-volume, complex samples having trace amounts of analytes due to superior elimination of background. Physical shape is an important and promising code system, which uses a set of visually distinct patterns to identify different assay particles. Here, we presented a morphology recognizable suspension arrays based on the microorganisms with different morphologies. In this study, UiO-66-NH2 (UiO stands for University of Oslo) metal-organic frameworks (MOFs), was wrapped on the microorganism surface to form an innovative class of microorganism@UiO-66-NH2 composites for suspension array assays. The use of microorganisms endowed composites barcoding ability with their different morphology and size. Meanwhile, the UiO-66-NH2 provided a stable rigid shell, large specific surface area, and metal(IV) ions with multiple binding sites, which could simplify the protein immobilization procedure and enhance detection sensitivity. With this method, simultaneous detection of three colorectal cancer-related microRNA (miRNA), including miRNA-21, miRNA-17, and miRNA-182, could be easily achieved with femtomolar sensitivity by using a commercial flow cytometer. The synergy between microorganisms and MOFs make the composites a prospective barcoding candidate with excellent characteristics for multicomponent analysis, offering great potential for the development of high throughput and accurate diagnostics.

Development of a Gas Chromatography-Flame Ionization Method for the Detection and Quantification of 12 Flavoring Agents in Supplementary Feed.

A flavoring agent is a compound that serves to add flavor with a pleasant scent and is used as a feed additive. Current flavor analysis methods include reflux pretreatment, titration, neutralization titration, and inversion; these are all analytical methods in which deviations and errors between experiments are generated. Titration methods are characterized by difficult selectivity analysis both for mixtures containing two or more types of flavoring agents and also for very low content samples. Current analysis methods are therefore particularly unsuitable for these sample types. Thus, more precise and accurate analysis of flavor agents is needed. This study intends to develop and verify a multi-component simultaneous analysis method that can accurately confirm the guaranteed content of 12 flavor agents of supplementary feeds distributed in the market, the goal being to establish a universally trusted method. Method validation was performed according to the International Conference on Harmonization (ICH) and International Union of Pure and Applied Chemistry (IUPAC) guidelines. Method validation was performed in terms of linearity, sensitivity, selectivity, accuracy, and precision. The limits of detection (LOD) for the instrument employed in these experiments ranged from 0.44-4.77 mg/kg, and the limits of quantification (LOQ) ranged from 1.32-14.31 mg/kg. Average recoveries of the 12 flavoring agents ranged from 75.1-111.4%. Maximum %RSD values for intraday and interday peak area variation are 13.09% and 13.08%, respectively. A novel and simple method for detecting 12 flavoring agents in animal feed supplements using a gas chromatography-flame ionization detector (GC-FID) was developed.

A Local Binary Pattern-Based Method for Color and Multicomponent Texture Analysis

Local Binary Patterns (LBPs) have been highly used in texture classification for their robustness, their ease of implementation and their low computational cost. Initially designed to deal with gray level images, several methods based on them in the literature have been proposed for images having more than one spectral band. To achieve it, whether assumption using color information or combining spectral band two by two was done. Those methods use micro structures as texture features. In this paper, our goal was to design texture features which are relevant to color and multicomponent texture analysis without any assumption. Based on methods designed for gray scale images, we find the combination of micro and macro structures efficient for multispectral texture analysis. The experimentations were carried out on color images from Outex databases and multicomponent images from red blood cells captured using a multispectral microscope equipped with 13 LEDs ranging from 375 nm to 940 nm. In all achieved experimentations, our proposal presents the best classification scores compared to common multicomponent LBP methods. 99.81%, 100.00%, 99.07% and 97.67% are maximum scores obtained with our strategy respectively applied to images subject to rotation, blur, illumination variation and the multicomponent ones.

Assessment of absorbed dose of gamma rays using the simultaneous determination of inactive hemoglobin derivatives as a biological dosimeter.

Biological dosimetry based on sulfhemoglobin (SHb), methemoglobin (MetHb), and carboxyhemoglobin (HbCO) levels was evaluated. SHb, MetHb and HbCO levels were estimated in erythrocytes of mice irradiated by γ rays from a 60Co source using the method of multi-component spectrophotometric analysis developed recently. In this method, absorption measurements of diluted aqueous Hb-solution were made at λ = 500, 569, 577 and 620nm, and using the mathematical formulas based on multi-component spectrophotometric analysis and the mathematical Gaussian elimination method for matrix calculation, the concentrations of various Hb-derivatives and total Hb in mice blood were estimated. The dose range of γ rays was from 0.5 to 8Gy and the dose rate was 0.5Gymin-1. Among all Hb-derivatives, MetHb, SHb and HbCO demonstrated an unambiguous dose-dependent response. For SHb and MetHb, the detection limits were about 0.5Gy and 1Gy, respectively. After irradiation, high levels of MetHb, SHb and HbCO persisted for at least 10days, and the maximal increase of MetHb, SHb and HbCO occurred up to 24h following γ irradiation. The use of this "MetHb + SHb + HbCO"-derivatives-based absorbed dose relationship showed a high accuracy. It is concluded that simultaneous determination of MetHb, SHb and HbCO, by multi-component spectrophotometry provides a quick, simple, sensitive, accurate, stable and inexpensive biological indicator for the early assessment of the absorbed dose in mice.

Multicomponent Analysis of Biomarkers in Exhaled Air Using Diode Laser Spectroscopy

We have proposed methods of multicomponent spectral analysis of exhaled air based on the use of tunable diode lasers to solve some problems in biomedical diagnostics. Simultaneous laser spectral analysis of CO and CO2, CO and N2O pairs near 4.7 µm can be used to examine gas exchange in the studies on the physiology of respiration and cardiovascular diagnostics conducted using various stress tests and for solving problems of anesthesiology and continuous monitoring ventilation–perfusion status. Simultaneous analysis of NO and CO2 at approximately 5.4 µm can be useful for monitoring the breathing maneuver in studies of inflammatory processes in the distal lungs. Simultaneous detection of NH3, CO2, and C2H4 near 10.5 µm is promising for studies of general metabolism and major metabolic cycles. Simultaneous analysis of 13CO2 and 12CO2 near 2.05 µm can be used to measure the ratio of 13CO2 to 12CO2 when conducting isotopic breathing tests. The results of the analysis of promising spectral ranges and the relative position of the analytical lines in them are given. The possibility of simultaneous detection of several molecules under study in the proposed spectral regions was experimentally demonstrated, and laser transmission spectra were obtained. The proposed approach can be applied to the analysis of the microcomposition of exhaled air.

Многокомпонентный анализ биомаркеров в выдыхаемом воздухе методами диодной лазерной спектроскопии-=SUP=-*-=/SUP=-

Methods of multicomponent spectral analysis of exhaled air based on application of tunable diode lases were proposed for biomedical diagnostics. Simmultaneous laser based spectral analysis of the gas pairs like CO and CO2, and CO and N2O in the 4.7 micron spectral region could be used for investigation of gas exchange in studies on breathing phisiology and cardiovascular diagnostics conducted with application of different loading tests, as well as for studies in anesteziology and for on-line monitoring of ventilation-perfusion ratio. Simmultaneous analysis of NO and CO2 in 5.4 micron region could be useful fot the control of breating maneuver in studies of inflammation processes in the distal part of the lungs. Simmultaneous detection of NH3, СO2 and C2H4 near 10.5 m could be promising in studies of basal metabolizm and metabolis cycles. Simmultaneous analisis of 13СO2 and 12С O2 near 2.05 m could be used for the detection of 13СO2/12СO2 izotope ratio for izotope breath tests. The results of promising spectral region analysis and of mutual location of absorption analytical lines in these regions are presented. A possibility of simmultaneous detection of several studied molecules in the provided spectral regions was experimetally demonstrated as well as experimental laser spectra of molecular absorption were obtained. A possibility of the proposed approach in applications to analysis of trace gases in exhaled air was demonstrated.

Deconvolution of ion mobility mass spectrometry arrival time distributions using a genetic algorithm approach: Application to α1-antitrypsin peptide binding

Ion mobility mass spectrometry (IM-MS) is a fast and sample-efficient method for analysing the gas phase conformation of proteins and protein complexes. Subjecting proteins to increased collision energies prior to ion mobility separation can directly probe their unfolding behaviour. Recent work in the field has utilised this approach to evaluate the effect of small ligand binding upon protein stability, and to screen compounds for drug discovery. Its general applicability for high-throughput screening will, however, depend upon new analytical methods to make the approach scalable. Here we describe a fully automated program, called Benthesikyme, for summarising the ion mobility results from such experiments. The program automatically creates collision induced unfolding (CIU) fingerprints and summary plots that capture the increase in collision cross section and the increase in conformational flexibility of proteins during unfolding. We also describe a program, based on a genetic algorithm, for the deconvolution of arrival time distributions from the CIU data. This multicomponent analysis method was developed to require as little user input as possible. Aside from the IM-MS data, the only input required is an estimate of the number of conformational families to be fitted to the data. In cases where the appropriate number of conformational families is unclear, the automated procedure means it is straightforward to repeat the analysis for several values and optimize the quality of the fit. We have employed our new methodology to study the effects of peptide binding to α1-antitrypsin, an abundant human plasma protein whose misfolding exemplifies a group of conformational diseases termed the serpinopathies. Our analysis shows that interaction with the peptide stabilises the protein and reduces its conformational flexibility. The previously unresolved patterns of unfolding detected by the deconvolution algorithm will allow us to set up a fully automated screen for new ligand molecules with similar properties.

Multicomponent quantitative spectroscopic analysis without reference substances based on ICA modelling.

A fast and reliable spectroscopic method for multicomponent quantitative analysis of targeted compounds with overlapping signals in complex mixtures has been established. The innovative analytical approach is based on the preliminary chemometric extraction of qualitative and quantitative information from UV-vis and IR spectral profiles of a calibration system using independent component analysis (ICA). Using this quantitative model and ICA resolution results of spectral profiling of "unknown" model mixtures, the absolute analyte concentrations in multicomponent mixtures and authentic samples were then calculated without reference solutions. Good recoveries generally between 95% and 105% were obtained. The method can be applied to any spectroscopic data that obey the Beer-Lambert-Bouguer law. The proposed method was tested on analysis of vitamins and caffeine in energy drinks and aromatic hydrocarbons in motor fuel with 10% error. The results demonstrated that the proposed method is a promising tool for rapid simultaneous multicomponent analysis in the case of spectral overlap and the absence/inaccessibility of reference materials.

Chemometrics-assisted spectrophotometric method for simultaneous determination of Pb2+ and Cu2+ ions in different foodstuffs, soil and water samples using 2-benzylspiro [isoindoline-1,5′-oxazolidine]-2′,3,4′-trione using continuous wavelet transformation and partial least squares – Calculation of pKf of complexes with rank annihilation factor analysis

A new multi-component analysis method based on zero-crossing point-continuous wavelet transformation (CWT) was developed for simultaneous spectrophotometric determination of Cu2+ and Pb2+ ions based on the complex formation with 2-benzyl espiro[isoindoline-1,5oxasolidine]-2,3,4 trione (BSIIOT). The absorption spectra were evaluated with respect to synthetic ligand concentration, time of complexation and pH. Therefore according the absorbance values, 0.015mmolL−1 BSIIOT, 10min after mixing and pH 8.0 were used as optimum values. The complex formation between BSIIOT ligand and the cations Cu2+ and Pb2+ by application of rank annihilation factor analysis (RAFA) were investigated. Daubechies-4 (db4), discrete Meyer (dmey), Morlet (morl) and Symlet-8 (sym8) continuous wavelet transforms for signal treatments were found to be suitable among the wavelet families. The applicability of new synthetic ligand and selected mother wavelets were used for the simultaneous determination of strongly overlapped spectra of species without using any pre-chemical treatment. Therefore, CWT signals together with zero crossing technique were directly applied to the overlapping absorption spectra of Cu2+ and Pb2+. The calibration graphs for estimation of Pb2+ and Cu 2+were obtained by measuring the CWT amplitudes at zero crossing points for Cu2+ and Pb2+ at the wavelet domain, respectively. The proposed method was validated by simultaneous determination of Cu2+ and Pb2+ ions in red beans, walnut, rice, tea and soil samples. The obtained results of samples with proposed method have been compared with those predicted by partial least squares (PLS) and flame atomic absorption spectrophotometry (FAAS).

Application of isoabsorption plots generated by high-performance liquid chromatography with diode array detection to the development of multicomponent quantitative analysis of traditional herbal medicines.

Multicomponent quantitative analysis is one of the mainstream quality control methods of traditional herbal medicines. Since the constituents of traditional herbal medicines samples are complex, the development of high-performance liquid chromatography methods is laborious. In this study, an isoabsorption plot, a chromatographic/spectrometric data image plotted by diode array detection was utilized to facilitate the establishment of a high-performance liquid chromatography method by optimizing and validating the detection conditions off-line. Consequently a simple, reliable and accurate method for simultaneous determination of seven active polyphenolic components (protocatechuic acid, chlorogenic acid, caffeic acid, p-coumaric acid, rosmarinic acid, scutellarin, and apigenin) in Qingfei mixture, a long-used Chinese prescription, was developed. The chromatographic separation was performed on a C18 column with gradient elution of phosphoric acid aqueous solution (0.05%, v/v) and acetonitrile, and a wavelength switch program optimized with isoplot was adopted for detection. The method was validated in terms of linearity, sensitivity, precision, repeatability, and accuracy and was successfully applied to the simultaneous determination of the seven polyphenolic components in different production batches of Qingfei Mixture. These results indicated that isoplot is an effective tool to improve the establishment of multicomponent quantitative analysis methods.