Simultaneous Analysis Method Research Articles

Comprehensive analysis of respiratory pharmaceuticals in dietary supplements using advanced chromatographic techniques

Recently, the number of people suffering from respiratory symptoms has continued to increase because of COVID-19 and particulate contamination. Accordingly, the demand for respiratory-related dietary supplements is increasing. Over the past few years, dietary supplements adulterated with pharmaceutical drugs have continued to appear, increasing the risk of side effects; thus, preventive measures are needed. In this study, we developed a simultaneous analysis method for 11 respiratory-related pharmaceutical compounds using ultra-performance liquid chromatography with a photodiode array (UPLC-PDA). The sample preparation method was optimized by comparing filtration and two clean-up methods (QuEChERS), for solid and liquid formulations, and the optimal analytical conditions were established by comparing various analysis parameters. Concerning method validation, all parameters meet International Council for Harmonisation guidelines. Subsequently, 54 types of dietary supplements promoting relief of respiratory-related symptoms were purchased online and analyzed using UPLC-PDA. As a result, theobromine, azelastine, and dexamethasone were detected in three products. In addition, the detected compounds were confirmed by comparing fragmentation patterns using liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF/MS). This study will contribute to preemptively blocking dietary supplements adulterated with respiratory-related drugs from entering the market and can be used as a reference for future research.

Simultaneous Analysis of 272 Pesticides in Agricultural Products by the QuEChERS Method and Gas Chromatography with Tandem Mass Spectrometry.

The aim of this study is to develop a rapid and accurate method for simultaneous analysis of multi-residue pesticides and conduct pesticide monitoring in agricultural products produced by the production and distribution stage in Korea. The representative agricultural products were selected as brown rice, soybean, potato, mandarin, and green pepper and developed using gas chromatography with tandem mass (GC-MS/MS) for the analysis of 272 pesticide residues. The experimental samples were extracted by the QuEChERS-EN method and then cleaned up by using d-SPE, including MgSO4 and primary secondary amine (PSA) sorbents. The established method was validated in accordance with Codex CAC-GL/40, and the limit of quantitation (LOQ) was determined to be 0.01 mg/kg. A total of 243 pesticides satisfied the guidelines in five samples at three levels with values of 60 to 120% (recovery) and ≤45% (coefficient of variation, CV). The remaining 29 pesticides did not satisfy the guidelines, and these pesticides are expected to be used as a screening method for the routine inspection of agricultural products. As a result of analyzing 223 agricultural products in South Korea by applying the simultaneous analysis method, none of the detected levels in the samples exceeded the standard values based on maximum residue limits (MRLs). The developed method in this study will be used to inspect residual pesticides in agricultural products, and it is anticipated to contribute to the distribution of safe agricultural products to consumers.

Development of a Simultaneous Analysis Method for 3-Carene, Limonene, and Terpinolene in Health Functional Foods Pine Needle Distilled Concentrate

Development of a Simultaneous Analysis Method for 3-Carene, Limonene, and Terpinolene in Health Functional Foods Pine Needle Distilled Concentrate

Metabolomic Analysis of Amino Acid and Organic Acid Profiles in Tissue From Ovarian Cancer Patients Using High-Performance Liquid Chromatography-Tandem Mass Spectrometry (HPLC-MS/MS) and Gas Chromatography-Tandem Mass Spectrometry (GC-MS/MS)

Targeted metabolomics studies on organic acids (OAs) and amino acids (AAs) were performed to search for biomarkers for ovarian cancer progression. Simultaneous AA profiling analysis method was developed through LC-MS/MS. Under optimal conditions, method showed good linearity (r ≥ 0.998) with limits of detection (LOD) ≤ 0.22 ng/mL and limits of quantification (LOQ) of ≤0.72 ng/mL. Repeatability varied from 1.4 to 17.3 relative standard deviation (%RSD) and accuracy varied from −20.6% to 12.1% relative error (% RE). Twenty-six AAs and 13 OAs were detected in the analyses of ovarian tissue from patients with benign ovarian tumors (BOT), borderline tumors (BT), and ovarian serous carcinoma (OSC). Star pattern recognition analysis was performed by normalizing each group to the BOT group. The star symbol plots in the BT and OSC groups were distinct and easily distinguished from those in the BOT group. The BT and the OSC groups exhibited higher 3-hydroxybutyric acid and lactic acid levels, lower pyruvic acid and OA levels in the TCA cycle, and alterations in AA metabolic patterns in comparison to the BOT group. Especially, citrulline and leucine were significantly reduced, while fumaric acid and malic acid significantly increased in the OSC group compared to the BT group. The BT and the OSC groups were completely separated in orthogonal partial least squares-discriminant analysis (OPLS-DA) and heatmap analysis. These findings, elevated ketone body levels, increased anaerobic glycolysis, reduced energy production related to mitochondrial dysfunction in the TCA cycle, and AA metabolic patterns associated with the impaired antioxidant system, may explain the characteristic metabolic reprogramming and Warburg effect related to the progression of the OSC into malignancy.

Establishment of Rapid Simultaneous Analysis Method for Plant Toxins by LC-TOF-MS

Assuming food poisoning caused by toxic plants, an LC-TOF-MS-based method for the rapid and simultaneous analysis of 16 plant toxins was established. After adding water-methanol (1 : 9) and n-hexane, the samples were homogenized and extracted, and then subjected to centrifugal separation. Without any purification procedures, LC-TOF-MS measurements were performed, and qualitative and quantitative analyses using monoisotopic ion [M+H]+ (m/z) were conducted. The addition-recovery test using curry showed that qualitative analysis was possible under a setting with a retention time of ±0.2 minutes or less and mass accuracy of 5 ppm or lower and that quantitative analysis was possible with a recovery rate of 68-142% and a repeatability of 1.4-10.1%. Furthermore, measurements of the amount of plant toxins in the boiled plants and broths of cooked toxic plants demonstrated the transfer of plant toxins to broths. These suggest that in the event of food poisoning, broths may be used as an analysis sample, even when plants are not available.

Development and validation of simultaneous HPLC-PDA analysis method for quality control of Hwang-ryeon-hae-dok-tang: An analytical quality by design approach

This study introduces an advanced analytical method for quality control of botanical drugs, focusing on Hwang-ryeon-hae-dok-tang (HRHDT), a traditional herbal prescription utilized for inflammation, gastritis, fever, and hypertension. Botanical drugs pose a challenge due to their complex composition, requiring reliable and robust analytical techniques. Our step-by-step procedure included defining the analytical target profile, risk assessment, screening and optimizing design of experiment, measuring the design space, and Monte Carlo simulation. The established HPLC-PDA method enables the simultaneous analysis of four major compounds (geniposide, baicalin, palmatine, and berberine) present in HRHDT. The optimized conditions involve a gradient elution with acetonitrile and water, both containing 0.1% trifluoroacetic acid, a 32 °C column temperature, 254 nm detection wavelength, and 1.0 mL/min flow rate. A successful validation demonstrated excellent linearity (R2: 0.9984–0.9989) and accuracy (recovery: 100.61%–102.44%), with precise repeatability and intermediate precision (%RSD: 0.39%–0.83%). These results further confirm the reliability and accuracy of the analytical method. Overall, our design-based approach not only facilitated the development of robust analytical methods but also allowed for flexible operation ranges. Therefore, this methodology holds significant potential for ensuring the quality of botanical drug products within the pharmaceutical industry.

Study of the characteristics of organic mining materials affecting their explosive properties

The article analyzes the explosive and fire-hazardous properties of coal dust of various dispersions using the example of coal mine dust. The authors proposed sample preparation methods for obtaining and studying dust fractions with a dispersity of less than 800 microns. The results of a study of the shapes of dust particles are presented. To study the characteristic particle sizes the authors suggested using the optical microscopy method implemented using a LEICA DM 4000 microscope and the “Image Scope Color” information processing application. To assess the reactivity of dust particles, the authors used a simultaneous thermal analysis method implemented using an STA 449 F1 Jupiter with NETZSCH Proteus Software. The results of a thermogravimetric study of narrow fractions of organic coal dust are presented. The influence of dispersion on the explosive properties of dusts has been established. The results obtained showed the need and expediency of further study of precisely fine fractions of explosive dusts of this kind.

In Situ Raman Methodology for Online Analysis of CO2 and H2O Loadings in a Water-Lean Solvent for CO2 Capture.

Carbon capture represents a key pathway to meeting climate change mitigation goals. Powerful next-generation solvent-based capture processes are under development by many researchers, but optimization and testing would be significantly aided by integrating in situ monitoring capability. Further, real-time water analysis in water-lean solvents offers the potential to maintain their water balance in operation. To explore data acquisition techniques in depth for this purpose, Raman spectra of CO2, H2O, and a single-component water-lean solvent, N-(2-ethoxyethyl)-3-morpholinopropan-1-amine (2-EEMPA) were collected at different CO2 and H2O concentrations using an in situ Raman cell. The quantification of CO2 and H2O loadings in 2-EEMPA was done by principal component regression and partial least squares methods with analysis of uncertainties. We conclude with discussions on how this simultaneous online analysis method to quantify CO2 and H2O loadings can be an important tool to enable the optimal efficiency of water-lean CO2 solvents while also maintaining the critical water balance under operating conditions relevant to post-combustion CO2 capture.

Identification and Simultaneous HPLC-PDA Quantification of Anti-glycation and α-Glucosidase Inhibitory Compounds From Atractylodes lancea Water Extract

Objective: The anti-diabetic efficacy of Atractylodes lancea water extract was verified by identifying the major active compounds, and quality control standards for water extracts were established by simultaneous HPLC quantification analysis. Methods: Thirteen compounds were isolated from the butanol fraction by bioactivity-guided approach using open-column chromatography. The compounds were identified by NMR and ESI/LTQ-Orbitrap-HRMS. The anti-diabetic activity was evaluated with anti-glycation and α-glucosidase assay. The simultaneous quantification by nine compounds was conducted by HPLC-PDA. Results: In total, 13 compounds from the butanol fraction were isolated. The water extract showed greater inhibitory effects than the hexane extract. Compounds 1, 2, 3, 5, 8, 10, 11, 12, and 13 showed high or significant activity. HPLC simultaneous analysis for these compounds was developed and validated to establish quality control standards, and the content standards of each compound were established through quantitative evaluation. Conclusion: To our knowledge, this study is the first to identify the main components and anti-glycation, α-glucosidase inhibitory activity of the water extract of A. lancea. This study scientifically and systematically established the quality control standards of traditional herbal medicine traditional herbal medicine through the development of a simultaneous HPLC quantitative analysis method and the establishment of content standards. It also demonstrates the potential of A. lancea water extract as a natural alternative treatment for diabetes.

A High-Performance Liquid Chromatography with Photodiode Array Detection Method for Simultaneous Determination of Three Compounds Isolated from Wikstroemia ganpi: Assessment of the Effects on Cytochrome P450-Mediated Metabolism In Vitro and In Vivo.

In natural products, the content and quality of the marker components differ depending on the part, production area, collection period, and extraction method; therefore, a standardized analysis method is required to obtain consistent results. This study developed a simultaneous analysis method for three marker components (7-methoxylutolin-5-O-glucoseide, pilloin 5-O-β-d-glucopyranoside, rutarensin) isolated and purified from Wikstroemia ganpi (W. ganpi). Simultaneous analysis was performed using high-performance liquid chromatography with photodiode array detection (HPLC-PDA) method that was validated according to the International Council for Harmonisation (ICH) guidelines. The developed analytical method exhibited linearity (r2 > 0.999), detection limits (0.72-3.34 μg/mL), and quantification limits (2.19-10.22 μg/mL). The relative standard deviation (RSD) value of intra- and inter-day precisions was less than 1.68%, and analyte recoveries (93.42-117.55%; RSD < 1.86%) were validated according to the analytical procedures, and all parameters were within the allowable range. Quantitative analysis of the three marker components from W. ganpi MeOH extract (WGM) showed 7-methoxylutolin-5-O-glucoseide with the highest content (51.81 mg/g). The inhibitory effects of WGM on cytochrome P450 (CYP) substrate drugs were further investigated. The in vitro study revealed that WGM inhibited the CYP3A-mediated metabolism of buspirone and that 7-methoxylutolin-5-O-glucoseide and pilloin 5-O-β-d-glucopyranoside inhibited the metabolism of buspirone with IC50 values of 2.73 and 18.7 μM, respectively. However, a single oral dose of WGM did not have significant effects on the pharmacokinetics of buspirone in rats, suggesting that WGM cannot function as an inhibitor of CYP3A-mediated metabolism in vivo.

Simultaneous determination of the free and total forms of nonylphenol, nonylphenol monoethoxylate, and nonylphenol diethoxylate in human urine by gas chromatography-mass spectrometry.

Nonylphenol (NP), nonylphenol monoethoxylate (NP1EO), and nonylphenol diethoxylate (NP2EO) are widely used in various daily products and have been cataloged as endocrine-disrupting chemicals. Due to their high lipophilicity and low biodegradability, these compounds remain in the environment and enter the human body through the food chain. Growing concerns regarding the potential negative effects of NP, NP1EO, and NP2EO on human health have raised the need for biomonitoring to investigate human exposure to these compounds. In this study, a simultaneous analysis method using solid-phase extraction (SPE) combined with gas chromatography-mass spectrometry (GC-MS) was established by controlling the background contamination of NP, NP1EO, and NP2EO, which are ubiquitous in laboratory environments. The proposed method showed proper linearity of over 0.999 and a recovery greater than 85.8% for all analytes. Accuracy and precision were verified in ranges of 92.97-116.30% and 0.65-9.29%, respectively. The detection limits for NP, NP1EO, and NP2EO were 0.0363μg L-1, 0.0401μg L-1, and 0.0364μg L-1, respectively, which were suitable for determining the trace analytes in human urine. Therefore, this simple and integrated analytical method was applied to measure the free and total forms of the target analytes in 25 human urine samples collected in Korea. Overall, free NP, NP1EO, and NP2EO were detected with average contents of 3.94 ± 4.14μg L-1, 4.63 ± 2.62μg L-1, and 0.293 ± 0.638μg L-1, respectively, and with total NP, NP1EO, and NP2EO contents of 6.14 ± 8.24μg L-1, 5.99 ± 2.91μg L-1, and 0.806 ± 1.10μg L-1, respectively. These data showed that these compounds are prevalent in human urine, and indicate the need for further studies.

P2E5-12 A method of simultaneous record and analysis of voice and high-density surface electromyography of laryngeal muscle

P2E5-12 A method of simultaneous record and analysis of voice and high-density surface electromyography of laryngeal muscle

Maxwell–Bloch equations without spectral broadening: the long-time asymptotics of an input pulse in a long two-level laser amplifier

We study the problem of propagation of an input electromagnetic pulse through a long two-level laser amplifier under trivial initial conditions. In this paper, we consider an unstable model described by the Maxwell–Bloch equations without spectral broadening. Previously, this model was studied by Manakov in (1982 Zh. Eksp. Teor. Fiz. 83 68–75) and together with Novokshenov in (1986 Teor. Mat. Fiz. 69 40–54). We consider this model in a more natural formulation as an initial-boundary (mixed) problem using a modern version of the inverse scattering transform method in the form of a suitable Riemann–Hilbert (RH) problem. The RH problem arises as a result of applying the Fokas–Its method of simultaneous analysis of the corresponding spectral problems for the Ablowitz–Kaup–Newell–Segur equations. This approach makes it possible to obtain rigorous asymptotic results at large times, which differ significantly from the previous ones. Differences take place both near the light cone and in the tail region, where a new type of solitons is found against an oscillating background. These solitons are physically relevant, their velocities are smaller than the speed of light. The number of such solitons can be either finite or infinite (in the latter case, the set of zeros has a condensation point at infinity). Such solitons cannot be reflectionless, they are generated by zeros of the reflection coefficient of the input pulse (and not by poles of the transmission coefficient). Thus our approach shows the presence of a new phenomenon in soliton theory, namely, the boundary condition (input pulse) of a mixed problem under trivial initial conditions can generate solitons due to the zeros of the reflection coefficient, while the poles of the transmission coefficient do not contribute to the asymptotics of the solution.

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.

Validation of the Ultra-Performance Liquid Chromatography with Tandem Mass Spectrometry Method for Simultaneous Analysis of Eighteen Compounds in the Traditional Herbal Prescription, Sanjoin-Tang

Sanjoin-tang (SJIT) is an ancient oriental medicine prescription listed in the Jinguiyaolue that is mainly used for the treatment of primary insomnia. This study was conducted to develop and validate an ultra-performance liquid chromatography with tandem mass spectrometry (UPLC–MS/MS) simultaneous analysis method for the quality control of SJIT using 18 target compounds. The 18 analytes were separated on an Acquity UPLC BEH C18 column maintained at 45 °C using a mobile phase composed of distilled water and acetonitrile. The MS system was used to simultaneously detect all analytes using the multiple reaction monitoring (MRM) method of Xevo TQ-XS coupled with an electrospray ionization source. The concentrations of the 18 analytes investigated in the SJIT samples ranged from below the limit of detection to 9.553 mg/g. In conclusion, the validated UPLC–MS/MS MRM analysis method can be used to obtain basic data to establish chemical-nonclinical linkage efficacy and for the clinical research and quality evaluation of SJIT.

액체크로마토그라피-질량분석기(LC-MS/MS)를 이용한 소변 중 신종 벤조디아제핀류 27종의 동시 분석법 개발

Benzodiazepines (BDZ) are mainly used as a tranquilizer for anxiety, tension and depression. These drugs have a potential for abuse and addiction, serious side effects may occur when used for a long time or in combination with other central nervous system inhibitors including alcohol. As the distribution of counterfeit medicines has increased, and new BDZ also have been sold on the illicit market, it is increasing possibility of abuse, and the risk of being used for crimes such as sexual assault and gambling fraud increases. In this study, we developed a simultaneous analysis method for 27 new BDZ in urine. The urine samples were hydrolyzed with β-glucuronidase, and extracted by solid-phase extraction (SPE). Liquid chromatography tandem mass spectrometry (LC-MS/MS) with electrospray ionization (ESI) positive mode was used for analysis. The analysis method was validated with respect of parameters such as limit of detection (LOD), limit of quantification (LOQ), accuracy, precision, matrix effect, recovery and efficiency. The LOD ranged from 0.5 to 5 ng/mL and LOQ ranged from 2 to 10 ng/mL. The accuracy and precision ranged from -18.5% to 13.3% and 0.2% to 18.4%, respectively. The matrix effect, recovery and efficiency range was 67% to 130%, 52% to 110% and 50% to 124%, respectively. Of the target substances covered in this study, 25 BDZ satisfied the validation criteria. By applying this analysis method to the forensic investigation, it could be a significant contribution to demonstrate new BDZ intoxication and abuse rapidly and accurately.

Investigation of agrillaceous rock properties by thermal analysis

Background. The importance of studying the properties of argillaceous rock materials is determined by their widespread application in various industries. At the same time, identification of argillaceous minerals is associated with a number of difficulties.Aim. To study the properties of argillaceous rock materials collected in different sites by the method of simultaneous thermal analysis to reveal their characteristic patterns and to identify their composition.Materials and methods. Natural materials from different geographical sites in Russia and neighboring countries were studied by the method of simultaneous thermal analysis.Results. The use of simultaneous thermal analysis for studying the properties of argillaceous materials allows their behavior to be studied under temperature exposure. The composition of rock samples can be identified by comparing their thermogravimetric curves with those of known rocks.Conclusion. The possibility of using thermal analysis for identifying the presumed mineral composition of the studied rock material was established. However, the diversity of soils on the planet impedes drawing a definite conclusion about their mineral composition. Therefore, thermal analysis should be applied in combination with other research methods, such as XRD, sediment, optical, etc., analytical techniques.

Polyampholite–Metal Complexes for Catalytic Processes

Polyampholyte–metal complexes based on polyacrylic acid; the aliphatic diamines ethylenediamine, 1,3-diaminopropane, and 1,4-diaminobutane; and Cu2+ was obtained by reacting aqueous solutions of polyampholytes and CuSO4. Using the method of simultaneous thermal analysis, it was found that the thermal degradation of the complexes occurs in three steps. The activation energy of thermal degradation of the polyampholyte–metal complexes is 22–99 kJ/mol. It was established by X-ray diffraction analysis that the products of thermal degradation of polyampholyte–metal complexes are heterogeneous systems composed of CuO and Cu2O phases, while catalysts based on them are heterogeneous systems consisting of Al2O3 and CuO phases. The size distribution of catalyst pores showed that the volume of pores with a diameter of less than 773 nm was 0.80–0.83 cm3/g, the specific surface area was 349–351 m2/g, and the predominant equivalent pore diameter was 6.2–6.3 nm. The mechanical crushing strength of catalyst pellets was found to be 7.1–7.3 MPa. In the process of CO oxidation to CO2, the catalyst began to exhibit its activity at 180–187°C; the complete conversion of CO in the oxidation reaction was achieved at 280–286°C. The performance of the obtained catalysts was 2.7–2.8 times higher than that of a reference sample.

Short-term forecast of U.S. COVID mortality using excess deaths and vector autoregression

We analyze overall mortality in the U.S. as a whole and several states in particular in order to make conclusions regarding timing and strength of COVID pandemic effect from an actuarial risk analysis perspective. No effort is made to analyze biological or medical characteristics of the pandemic. We use open data provided by CDC, U.S. state governments and Johns Hopkins University. In the first part of the paper, we suggest time series analysis (ARIMA) for weekly excess U.S. mortality in 2020 as compared to several previous years’ experience in order to build a statistical model and provide short-term forecast based exclusively on historical mortality data. In the second half of the paper, we also analyze weekly COVID cases, hospitalizations and deaths in 2020 and 2021. Two midwestern states, Minnesota and Wisconsin, along with geographically diverse Colorado and Georgia, are used to illustrate global and local patterns in the COVID pandemic data. We suggest vector autoregression (VAR) as a method of simultaneous explanatory and predictive analysis of several variables. VAR is a popular tool in econometrics and financial analysis, but it is less common in problems of risk management related to mortality analysis in epidemiology and actuarial practice. Efficiency of short-term forecast is illustrated by observing the effect of vaccination on COVID development in the state of Minnesota in 2021.

Analysis of Furan and Its Derivatives in Food Matrices Using Solid Phase Extraction Coupled with Gas Chromatography-Tandem Mass Spectrometry.

The objective of this study was to develop a simultaneous analysis method of furan and its 10 derivatives in different food commodities. The results indicated that furan and its 10 derivatives could be separated within 9.5 min by using a HP-5MS column and gas chromatography-tandem mass spectrometry (GC-MS/MS) with multiple reaction monitoring mode for detection. Furthermore, this method could resolve several furan isomers, such as 2-methyl furan and 3-methyl furan, as well as 2,3-dimethyl furan and 2,5-dimethyl furan. The most optimal extraction conditions were: 5 g of the fruit or juice sample mixed with 5 mL of the saturated NaCl solution, separately, or 1 g of the canned oily fish sample mixed with 9 mL of the saturated NaCl solution, followed by the equilibration of each sample at 35 °C for 15 min, using a carboxen-polydimethylsiloxane SPME arrow to adsorb the analytes for 15 min at 35 °C for subsequent analysis by GC-MS/MS. For method validation of all the analytes in the different food matrices, the recovery was 76-117% and the limit of the quantitation was 0.003-0.675 ng/g, while the relative standard deviation (RSD%) of the intra-day variability range from 1-16%, and that of the inter-day variability was from 4-20%. The method validation data further demonstrated that a reliable method was established for the analysis of furan and its 10 derivatives in commercial foods.