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Acta Chromatographica
Authors:
Thanh Duy Nguyen
,
Thuy Ngan Ha Nguyen
,
Tuan Kiet Ly
,
Thanh Tho Le
,
Ngoc Minh Truong
,
Tien Dat Nguyen
, and
Quoc Hung Nguyen

Abstract

Aflatoxins, potent carcinogenic mycotoxins produced by Aspergillus species, persist in various foods, posing significant health risks upon consumption. This study assesses dietary aflatoxin B1 (AFB1) exposure in Vietnam using Margin of Exposure (MOE) and Hazard Index (HI) to evaluate risk levels in peanuts, chili powder, corn, and raisins. AFB1 levels were quantified by UPLC-FLD. AFB1 was detected in 71.5% of chili powder, 29.3% of peanuts, and 26.0% of corn samples, with no detectable levels in raisins. Peanuts and corn kernels were classified as high-risk, with MOE values below 10,000 (peanuts: 25.8–56.6; corn: 42.3–92.6) and HI values exceeding 1, potentially contributing to 20.4–44.7 and 12.5–27.3 liver cancer cases per 100,000 adults, respectively. In contrast, chili powder had MOE values between 3,208 and 7,021 and HI below 1, indicating a low public health risk. Raisins were deemed safe with MOE over 200,000 and HI at 0.01. Results also indicated higher cancer risk for women and lean individuals consuming the same AFB1 levels. These findings underscore the need for focused risk management strategies to mitigate AFB1 exposure and protect public health in Vietnam.

Open access
Acta Chromatographica
Authors:
Muhammad Sajid Nawaz
,
Muhammad Hasnat
,
Muhammad Zaman
,
Majid Alhomrani
,
Abdulhakeem S. Alamri
,
Waqar Siddique
,
Muhammad Amer
,
Qurat-ul-ain shoaib
, and
Kanwal Shahzadi

Abstract

In the field of pharmaceutical analysis, high-performance liquid chromatography (HPLC) is considered to be the key technique, which is one of the most efficient, quick, and easy methods for the simultaneous determination of two are more drugs. The purpose of the current study is to develop and validate the reversed-phase high-performance liquid chromatographic (RP-HPLC) method for the simultaneous determination of Paracetamol and Fexofenadine HCl. This approach was validated by the standards and The International Conference on Harmonization (ICH), and United States Pharmacopeia (USP) were followed in the development and validation of the method. The chromatographic conditions including a mobile phase comprised of a 35:65 buffer mix and acetonitrile with a 1.0 mL min−1 flow rate were used. A thorough investigation was performed, including linearity and range, specificity, robustness, accuracy, precision, solution stability, and system suitability. The outcomes of the studies have shown that, both Active Pharmaceutical ingredients i.e., Paracetamol and Fexofenadine HCl were separated in about 7.5 min. The variation coefficient for Paracetamol and fexofenadine HCl varied between 0.9992 R 2 and 0.9983 R 2, respectively. The devised method was proved accurate, as API recoveries in both cases of Paracetamol and Fexofenadine ranged from (99.79%, 100.72%, and 98.64%) to (99.96%, 100.64%, and 99.00%). The method's accuracy was further demonstrated by the solution stability which was 99.84% for Paracetamol, and 100.53% for Fexofenadine HCl. The suggested method for simultaneously measuring Paracetamol and Fexofenadine HCl was established, validated, and there was no evidence of any excipient interaction was observed.

Open access

Abstract

The need to develop environmentally friendly analytical approaches has driven the pharmaceutical industry to seek greener alternatives. Ultra-Performance Liquid Chromatography (UPLC) is known for its efficiency but traditionally relies on toxic solvents. Integrating Green Analytical Chemistry (GAC) principles aims to address environmental concerns while maintaining analytical performance. This work aims to advance and authenticate a green, efficient UPLC method for the concurrent quantification of Metformin (MET) and Empagliflozin (EPI) in tablet formulations, adhering to green chemistry principles and ensuring high analytical accuracy. The method was optimized using a UPLC-PDA system with a phenyl column and a mobile phase of ethanol and perchloric acid. Analytical Quality by Design (AQbD) was employed to optimize critical method parameters. Environmental impact was assessed using metrics such as GAPI, AMGS, and AGREE. Degradation studies under various stress conditions were performed to test method robustness. The method achieved high recovery rates for MET and EPI, with minimal interference from excipients. The environmental evaluation showed a high Analytical Eco-Score (AES) of 97, indicating low environmental impact. The AGREE score of 0.89 confirmed excellent alignment with green chemistry principles. Degradation studies confirmed the method's stability and reliability under stress conditions. The developed UPLC method demonstrates a significant advancement in analytical sustainability, offering an eco-friendly, efficient, and precise approach to drug analysis. The method's high alignment with green chemistry principles and its effectiveness in quantifying MET and EPI highlight its potential as a model for sustainable analytical practices in pharmaceutical analysis.

Open access

Abstract

Tea's beneficial effects have long been attributed to its abundance of natural bioactive compounds; however, the influence of variations in these compounds on taste and aroma remains poorly understood. To investigate the relationship between metabolomic profiles and tea processing adaptability, this study employed sensory evaluation and untargeted metabolomics to compare four tea cultivars from Guangxi—Ying Hong No.9 (YH), Gui Hong No.3 (GH), Gui Cha No.2 (GC), and Mei Zhan (MZ)—cultivated under the same conditions. Sensory evaluation revealed that GH and MZ exhibited the highest quality in green tea and black tea, respectively, while GC showed moderate quality, and YH performed less favorably than the other three cultivars. Metabolomics analysis uncovered significant differences in the metabolic profiles among the four tea cultivars, with MZ and YH displaying higher levels of flavonol glycosides, and GC and GH showing elevated levels of organic acids and fatty acids. Pathway analyses of GH and MZ indicated that the differentially enriched pathways were primarily related to linoleic acid metabolism and flavonoid and flavanol synthesis. Correlation analyses further revealed that the sensory quality of green tea was closely linked to fatty acids and organic acids in fresh leaves, whereas the sensory quality of black tea was strongly associated with flavonol glycoside levels. This study provides a comprehensive understanding of the complex relationship between metabolite characteristics and processing suitability in different tea cultivars, offering valuable insights into the development of tea germplasm resources in the Guangxi region.

Open access

Abstract

This research dealing with salting out TLC technique for simultaneous determination of two antihistaminic drugs Loratadine and its active metabolite desloratadine in pure, tablets and rabbit spiked plasma. Separation was performed on silica gel 60 F254 plates using aqueous ammonium sulfate and acetonitrile (6:4, v/v) as a mobile phase. The R f values were 0.51 ± 0.02 and 0.70 ± 0.004 for Loratadine and desloratadine, respectively in pure or dosage form while in spiked plasma R f values were 0.39 ± 0.004 and 0.61 ± 0.004 for both drugs respectively using levocetirizine as internal standard (R f 0.74 ± 0.004). The separated bands were scanned under UV light at λ 254 nm and the TLC chromatograms were captured by camera and treated with Image J software. Method validation was according to ICH and complied with USP31- NF26 guidelines. The correlation coefficients of calibration curves were 0.997 and 0.998 for Loratadine and desloratadine in pure and dosage form while in rabbit spiked plasma were 0.996 and 0.995 for both drugs respectively in the range 100–2,000 μg mL−1. limits of detection LOD and limits of quantitation LOQ for Loratadine and desloratadine were 7.84, 30.06 and 23.52, 91.18 μg mL−1 respectively as pure or as dosage form while LOD and LOQ in rabbit spiked plasma were 17.46, 14.03 and 52.38 and 42.09 μg mL−1 respectively.

Open access
Acta Chromatographica
Authors:
Feifei Lin
,
Runrun Wang
,
Jingye Du
,
Congcong Wen
,
Xianqin Wang
,
Yongxi Jin
, and
Lingjiu Shao

Abstract

Febrifugine, a potent quinazolinone compound derived from the Chinese herb Chang Shan (Dichroa febrifuga), exhibits diverse biological activities and has demonstrated anti-tumor effects by functioning as focal adhesion kinase (FAK) inhibitors. In this study, our objective was to establish a quantitative UPLC-MS/MS method and investigate the pharmacokinetic characteristics of febrifugine in rats following intravenous and oral administration routes. The rat tail vein was used for the collection of blood samples at designated time intervals following intravenous (2.0 mg kg−1) and oral (6.0 mg kg−1) administrations. Plasma samples were pretreated with acetonitrile as a protein precipitant and methylcytisine as an internal standard. Febrifugine concentration in rat plasma was determined using the UPLC-MS/MS method, and pharmacokinetic parameters were calculated using drug and statistics (DAS) software version for statistical analysis. The linear range of febrifugine in rat plasma was 1.5–1,500 ng mL−1, meeting the precision, recovery, and stability requirements for determination purposes. Febrifugine had a half-life (t1/2) of 3.2 ± 1.6 h after administered via intravenous route, while t1/2 was 2.6 ± 0.5 h after oral administration. The developed UPLC-MS/MS method is facile to operate while adhering to rigorous methodological verification standards, rendering it suitable for investigating the pharmacokinetics of febrifugine; and bioavailability was determined as 45.8%.

Open access

Abstract

This study presents the development and validation of a robust HPLC-UV method for the simultaneous detection and quantification of vitamin D2, vitamin D3, ergosterol, and 7-dehydrocholesterol in a single analytical run, adhering to ICH Q2 (R1) guidelines. Application of the HPLC-UV method to six vegetable oils demonstrated inherent vitamin D content and its enhancement under different radiation conditions. Oils were exposed to direct sunlight, UVA, and UVB radiation, with UVB showing the most significant impact on vitamin D levels. Notably, UVB exposure increased vitamin D3 in castor oil from 2.82 μg mL−1 to 4.29 μg mL−1 and vitamin D2 in mustard oil from 0.73 μg mL−1 to 1.89 μg mL−1. The findings highlight the potential of UVB radiation to convert vitamin D precursors to active forms more effectively than other radiation sources. This study provides a novel approach for naturally enriching vitamin D in vegetable oils, offering a promising strategy to mitigate vitamin D deficiencies in populations with limited sun exposure or dietary restrictions. The developed HPLC-UV method and resultant insights into the radiation-induced enhancement of vitamin D content in oils contribute valuable knowledge to nutritional science.

Open access

Abstract

Zanubrutinib (Brukinsa, BeiGene) is a FAD approved second-generation Bruton's tyrosine kinase inhibitor that has more selectivity and reduced off-target action, resulting in mitigated cardiotoxicity compared to ibrutinib. The target of this investigation was to establish a fast, precise, green, and extremely sensitive UPLC-MS/MS approach for quantifying the level of zanubrutinib (ZNB) in human liver microsomes (HLMs). The separation of ZMB and revumenib was achieved using C8 column and isocratic gradient of the mobile phase. The linearity of the constructed ZNB calibration curve was ranged from 1 to 3,000 ng mL−1. The StarDrop software package including DEREK and WhichP450 modules was used in screening for the toxic alerts the in silico metabolic lability of ZNB. The AGREE score was 0.76 that approves the greenness of the established method. The low in vitro t1/2 (17.61 min) and high intrinsic clearance (46.03 mL min−1 kg−1) of ZNB revealed that ZNB shares similarities with medications that have a high extraction ratio. The present LC-MS/MS approach is considered the first analytical methodology for assessment of ZNB metabolic stability in HLMs matrix. In silico data from WhichP450 and DEREK modules suggest that making small structural changes (bioisosteric replacement) to the carboxamide moiety during drug design can potentially improve the metabolic safety and stability of novel compounds relative to ZNB. These methods are essential for advancing the development of new pharmaceuticals, particularly in enhancing metabolic stability.

Open access

Abstract

Eleutherococcus senticosus (Rupr. & Maxim.) Maxim. fruits (ESF) is a natural health food that has been widely used in traditional medicine. This study aimed to establish and validate a rapid and sensitive method for determining of six phenolic acids in plasma of normal and T2DM rats by ultra-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS). Separation and quantification were performed on a Waters HSS T3 column (100 × 2.1 mm, 1.8 μm) with water (A) and methanol (B). The electrospray ionization (ESI) source was operated in negative ionization mode. Multiple reaction monitoring (MRM) was used to quantitatively analyzed hyperoside m/z 463.2→301.1, caffeic acid m/z 179.1→135.1, chlorogenic acid m/z 353.2→190.9, gallic acid m/z 169.0→125.1, protocatechuic acid m/z 153.1→109.1, and isofraxidin m/z 221.1→191.0, respectively. The hypoglycemic effect of ESF was verified by determining blood glucose and lipid levels in a type 2 diabetes model. This study laid the foundation for exploring ESF clinical guidelines in the future.

Open access

Abstract

High Performance Thin Layer Chromatography has capacity to run many samples simultaneously and its reduced solvent usage. Simultaneous quantification of gallic acid, ferulic acid, rutin and berberine in Asthimajja Pachak Kwath has been developed and validated using a specific, precise, accurate, and low-cost high performance thin layer chromatography technique. Toluene: ethyl acetate: chloroform: methanol: formic acid (5:2:2:2:1, v/v/v/v/v) was used as mobile phase during separation, which took place on a stationary phase of pre-coated silica gel aluminum plate 60 F254. At 270 nm, separated components were densitometrically measured. The method was validated for linearity and range, precision, reproducibility, specificity, robustness, accuracy, limit of detection and limit of quantification as per International Council for Harmonization Q2 (R2) guideline. Gallic acid, ferulic acid, rutin and berberine regression coefficients (R 2) were found to be 0.9995, 0.9990, 0.9985 and 0.9997 accordingly. Gallic acid, ferulic acid, rutin and berberine percentage recoveries were measured to be 99.81 ± 0.833, 99.15 ± 0.776, 99.56 ± 0.582 and 99.90 ± 0.719 respectively. Having a reliable analytical method is essential for ensuring the quality, consistency, and efficacy of herbal formulations in traditional medicine. This meticulous approach is crucial for accurate quantification of the target compounds in the Asthimajja Pachak Kwath.

Open access