Photodiode Array Detector Research Articles

Advanced HPLC Method with Diode Array Detection Using a Phenyl-Bonded Column for Simultaneous Quantitation of Three Sunscreen Filters in a Moisturizing Sunscreen Cream for Acne-Prone Skin

This study introduces a novel, robust, and efficient method for the simultaneous quantitative determination of three sunscreen filters, namely, 4-methylbenzylidene camphor, octyl methoxycinnamate, and avobenzone, in a moisturizing sunscreen cream specifically designed for acne-prone skin. The method employs high-performance liquid chromatography with photodiode-array detection, providing a reliable separation of the analytes. Chromatographic separation was achieved using a Fortis Phenyl analytical column (150.0 × 2.1 mm, 5 μm), with isocratic elution at a flow rate of 0.4 mL/min. The mobile phase was composed of a 57/43 (v/v) mixture of acetonitrile/45 mM aqueous ammonium formate solution, ensuring sufficient resolution and peak symmetry for the target compounds. The method was validated comprehensively for critical performance parameters, including linearity, precision, accuracy, and robustness. Linearity was established across a suitable range for all three analytes, with high correlation coefficients. Precision was confirmed with intra-run and total precision coefficients of variation of ≤4.6%, while accuracy assessments yielded a percent recovery between 98.6 and 100.4, for all quality control levels. Additionally, the method was able to effectively separate the sunscreen filters from other cosmetic ingredients, such as [β-(1.3), (1.6)-D-glucan], low molecular weight (LMW) hyaluronic acid and plant extracts ensuring specificity in complex formulations. This straightforward and time efficient sample preparation process, involving methanol extraction followed by serial dilution, makes the method suitable for routine quality control in cosmetic laboratories. The method was successfully applied to the analysis of two different lots of a commercial sunscreen cream, achieving excellent recovery for all filters, ranging between 94.6% and 99.8%, thus demonstrating its reliability and applicability for the quality control of cosmetics.

Suspended Stir Bar Sorptive Extraction Based on Zr-MOF-Modified Cotton Thread for Enrichment and Detection of Three Trace Quinolones in Fish Tissue.

In this study, an efficient and practical method was established to enrich and detect three trace quinolones in fish tissue. Low-cost and environment-friendly cotton threads were coated with PCN-224 using a simple one-pot hydrothermal method. The PCN-224-modified cotton threads (PCN-224@CTs) were characterized to ensure that the crystal was successfully fabricated on the surface of cotton threads. The prepared PCN-224@CTs were wrapped around steel needles to form suspended bars. Key factors of extraction and desorption were optimized, and analytical performance was tested. Suspended bar sorptive extraction coupled with ultra-performance liquid chromatography (UPLC) with a photodiode array detector was used to analyze the quinolones in fish tissue. The detection limits of quinolones were 0.26-1.15ng/mL, and the recoveries were achieved in the range of 81.31%-115.81%, indicating a simple method with high sensitivity and satisfactory practicability of enriching, separating, and detecting trace quinolones was successfully established.

Development and Validation of a New Eco-Friendly HPLC-PDA Bioanalytical Method for Studying Pharmacokinetics of Seliciclib

Background and Objectives: Seliciclib (SEL) is the first selective, orally bioavailable potential drug containing cyclin-dependent kinase inhibitors. Preclinical studies showed antitumor activity in a broad range of human tumor xenografts, neurodegenerative diseases, renal dysfunctions, viral infections, and chronic inflammatory disorders. To support the pharmacokinetics and aid in therapeutic monitoring of SEL following its administration for therapy, an efficient analytical tool capable of quantifying the concentrations of SEL in blood plasma is needed. In the literature, there is no existing method for quantifying SEL in plasma samples. This study introduces the first HPLC method with a photodiode array (PDA) detector for the quantitation of SEL in plasma. Materials and Methods: The chromatographic resolution of SEL and linifanib as an internal standard (IS) was achieved on Zorbax Eclipse Plus C18 HPLC column (150 mm length × 4.6 mm internal diameter, 5 µm particle size), with a mobile phase composed of acetonitrile–ammonium acetate, pH 5 (50:50, v/v) at a flow rate of 1.0 mL min−1. Both SEL and IS were detected by PDA at 230 nm. The method was validated according to the ICH guidelines for bioanalytical method validation. Results: The method exhibited linearity in concentrations ranging from 50 to 1000 ng mL−1, with a limit of quantitation of 66.1 ng mL−1. All remaining validation parameters satisfied the ICH validation criteria. The environmental sustainability of the method was verified using three extensive tools. The proposed HPLC-PDA method was effectively utilized to study the pharmacokinetics of SEL in rats after a single oral administration of 25 mg/kg. Conclusions: The proposed method stands as a valuable tool for studying SELs for pharmacokinetics in humans. It aids in achieving the targeted therapeutic advantages and safety of treatment with SEL by optimizing the SEL dosage and dosing schedule.

Evaluation of selenocysteine contents in Se-enriched yogurt by Utilizing online post column derivative − High-Performance liquid chromatography

This study demonstrated a novel method using online post-column derivatization high-performance liquid chromatography (PCD-HPLC) to evaluate selenocysteine (SeC) in Se-enriched yogurt. The liquid chromatography process utilized a C18 column. The mobile phase A was composed of 4.0 mM borate buffer adjusted to pH 5.0, while mobile phase B was a 50:50 (v/v) mixture of methanol and acetonitrile. The mobile phases were combined at a ratio of 70:30, with a flow rate of 1 mL min−1. SeC was derivatized to bis-Fmoc selenocystine after separation, using a PCD solution (0.03 mM Fmoc, pH 10, 20 mM borate buffer, and 1.0 mL min−1 flow rate) and detected with a photodiode array detector (DAD) for sensitivity enhancement. The method exhibited excellent linearity (0.023 to 0.20 mg L-1, r2 = 0.9996), with a low LOD and LOQ of 0.018 mg L-1 and of 0.040 mg L-1, respectively. Repeatability and reproducibility were satisfactory, with recoveries of 95.50 % ± 1.49 % (the proposed PCD-HPLC) and 94.33 % ± 0.44 % (sample preparation). This method effectively analyzed the conversion of selenite ions (SeO32-) to SeC by lactic acid bacteria in yogurt, highlighting Se-enriched yogurt as a valuable dietary source of SeC. However, the synthesis efficiency of SeC decreased at inorganic Se supplementation levels above 1.0 mg Se L-1, potentially leading to the formation of less toxic elemental Se (Se0). Therefore, the proposed online PCD-HPLC method proves reliable for SeC analysis in Se-enriched yogurt, providing insights into Se speciation and optimizing Se enrichment processes.

Green and Sensitive Analysis of the Antihistaminic Drug Pheniramine Maleate and Its Main Toxic Impurity Using UPLC and TLC Methods, Blueness Assessment, and Greenness Assessments

For the first time, two direct and eco-friendly chromatographic approaches were adapted for the simultaneous estimation of pheniramine maleate (PAM) and its major toxic impurity, 2-benzyl pyridine (BNZ). Method A used reversed-phase ultra-performance liquid chromatography; separation was achieved within 4 min using a C18 column with a developing system of methanol/water (60:40 v/v) with a 0.1 mL/min flow rate. Photodiode array detection was adjusted at 215 nm. The method was linear in the ranges of 5.0–70.0 and 0.05–10.0 µg/mL for PAM and BNZ, correspondingly. Method B used thin-layer chromatography; separation was applied on silica gel TLC F254 using ethanol/ethyl acetate/liquid ammonia (8:2:0.1, in volumes) at room temperature, at 265 nm. Linearity was assured at concentration ranges 0.5–8.0 and 0.1–3.0 µg/band for the two components, respectively. Generally, the new UPLC and TLC methods outperform the old ones in terms of quickness, greenness, and sensitivity. Concisely, the greenness features were partially achieved using the Green Analytical Procedure Index (GAPI) and the Analytical Greenness (AGREE) pictograms. In contrast, the usefulness of the novel approaches was assured via the Blue Applicability Grade Index (BAGI) tool.

Potential Sampling Errors in Stability Studies Due to Dead Volume in Closed System Transfer Devices

Background: Closed system transfer devices (CSTD) help to reduce the exposure of healthcare professionals to hazardous drugs. They may be used in stability studies conducted on anticancer drugs. During a stability study about polyolefin bags of gemcitabine, Tevadaptor® device was suspected of causing a bias in the evaluation of the concentrations of the first aliquots extracted from the bags. Objective: The objectives are to determine whether the use of a CSTD to prepare a drug solution and to withdraw it from a bag can interfere on the measured concentration compared to the expected one and to suggest hypothesis to explain the phenomenon. Method: In the first experiment, three polyolefin bags of gemcitabine (5.4 mg/mL) were prepared under aseptic conditions using the Tevadaptor Luer Lock Adaptor®. The day of preparation, five aliquots of 3.8 ml each were sequentially withdrawn from each polyolefin bag using the same device. After one day, a new aliquot was withdrawn from each bag. In the second experiment, three polyolefin bags of gemcitabine (5.4 mg/ml) were prepared under aseptic conditions using a needle. One aliquot was extracted using a needle after the preparation from each bag, and another aliquot was extracted after one day. The concentrations of all aliquots were measured by liquid chromatography coupled to a photodiode array detector during the same run. Results and discussion: The concentrations of the first aliquots extracted on day zero from the polyolefin bags using the Tevadaptor Luer Lock Adaptor® exhibit an overestimation of 26% ([95%CI: 23%-29%] P<0.001) compared to the others. Overestimation is not found for subsequent aliquots, or while using a needle to bypass the Tevadaptor® device. Conclusion: This case highlights the bias that may arise when using CSTDs in stability studies. They should be used with comprehensive understanding of their technical specifications.

In vial thin-film solid-phase microextraction using silver nanoparticles as coating for the determination of phenols in waters

A novel thin-film solid-phase microextraction (TF-SPME) device based on glass vials internally coated with silver nanoparticles (AgNPs) was developed for the first time, and used for determining five phenols in wastewater, bottled water, and irrigation water samples by high-performance liquid chromatography coupled to a photodiode array detector (HPLC-PDA). Different AgNPs were synthesized varying the ratio of metallic salt versus the reduction agent, and the pH of the synthesis. The preparation of the TF-SPME glass vial device was optimized in terms of the type of AgNPs used and the number of layers of AgNPs. Besides, the TF-SPME procedure was also optimized. The TF-SPME method was very simple, only requiring the addition of 18 mL of water and 5 min of agitation, followed by the disposal of the water and addition of the 750 µL as desorption solvent, and direct HPLC-PDA injection. The entire method showed adequate analytical performance, with limits of detection ranging from 3 to 8 μg·L-1, and intra-day and inter-day precision (as RSD), both evaluated with different vials and therefore showing inter-batch precision, with values between 8.70 and 16.4 %, and 6.0 and 19.7 %, respectively. The TF-SPME-HPLC-PDA procedure was compared with previous methods for the determination of phenols, both in terms of analytical performance and greenness assessments applying different metrics, showing clear advantages.

The HPLC-PDA Method for Simultaneous Determination of Regalosides from Bulbs of Lilium lancifolium Thunb. and Their Antioxidant Effects.

Lilium lancifolium Thunb. is a herbal medicine that is widely used to treat inflammation and lung diseases. In this study, a simultaneous quantitative method was developed for the quality control of BLL using high-performance liquid chromatography coupled with a photodiode array detector (HPLC-PDA), and their antioxidant effects were evaluated. Eight regalosides (i.e., regaloside A, B, C, E, F, H, I, and K) were selected as marker substances and separated on a Gemini C18 reversed-phase analytical column by gradient elution with distilled water-acetonitrile mobile phase containing 0.1% (v/v) formic acid. The method was validated with respect to linearity, sensitivities (limit of detection (LOD) and limit of quantitation (LOQ)), accuracy, and precision. The antioxidant effects of the extract and each component were evaluated using the 2,2-diphenyl-1-picrylhydrazyl radical scavenging assay and 2-2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) assay. The coefficients of determination values used as indicators of linearity for all components were ≥0.9999. LOD and LOQ concentrations were 0.10-0.66 μg/mL and 0.29-2.01 μg/mL, respectively. The recovery was 95.39-103.925% (relative standard deviation; RSD ≤ 2.55%), and precision RSD was <2.78%. The HPLC-PDA method was applied to real samples, and all components were detected at 1.12-29.76 mg/freeze-dried g. The evaluation of antioxidant effects showed that regalosides C, E, and K exhibited significant antioxidant effects. Our knowledge will be appropriately utilized in raw material management and conducting clinical and non-clinical studies on L. lancifolium or herbal medicine prescriptions containing L. lancifolium.

Insights into the wound-healing properties of medicinally important South African Bulbine species – A comparative study

Ethnopharmacological relevanceSouth Africa harbours a large number of Bulbine (Xanthorrhoeaceae) species, which includes ethnobotanically important indigenous species. Traditionally, Bulbine leaves are used by several ethnic groups in South Africa to treat dermatological conditions including wounds, which led to the development of Bulbine-containing cosmetic products. However, scientific evidence is needed to support the claims in treating skin conditions and wound-healing. Aim of the studyThis comparative study was undertaken to investigate the wound-healing properties of five Bulbine species indigenous to South Africa, using in vitro and in vivo models. Materials and methodsFive Bulbine species, B. abyssinica, B. asphodeloides, B. frutescens, B. latifolia and B. narcissifolia were collected from natural populations in the Eastern Cape Province of South Africa. The chemical profiles of the methanol leaf extracts were acquired using ultra-performance liquid chromatography with photodiode array detection in tandem with quadrupole time-of-flight mass spectrometry. The methyl thiazolyl tetrazolium (MTT) assay and maximum tolerated concentration (MTC) assay were used to assess the in vitro and in vivo toxicity of the extracts, respectively. The in vitro scratch assay was employed to monitor cell migration and wound-closure in a HaCaT cell monolayer, following treatment with the plant extracts for 48 h. In vivo wound-healing potential was determined using the zebrafish larvae caudal fin amputation assay, assessed in three-days post fertilization larvae and various concentrations of the plant extracts were tested in both assays to determine the concentration-response effect. Data were analysed using MS Excel® enhanced with the Real Statistics add-in. Results and discussionUsing UPLC-MS, 11 major compounds were tentatively identified in the five Bulbine species. Although the compounds varied between species, all five Bulbine species contained the phenylanthraquinone, knipholone. Kaempferol glucoside was identified in four species, but not in B. abyssinica. The five Bulbine species were non-cytotoxic (cell viability > 80%) towards keratinocytes at all three tested concentrations. However, B. latifolia was toxic towards zebrafish larvae at all the tested concentrations, while the other four species were non-toxic at low concentrations. The results of the scratch assay revealed that B. abyssinica was the most active extract at 100 μg/mL. Compared to the untreated control, wound-closure notably increased by 28% (p < 0.05), 44% (p < 0.01) and 34% (p < 0.05) after 12 h, 24 h and 36 h post-treatment, respectively. Although none of the species achieved 100% caudal fin regeneration by the end of the treatment period, B. frutescens demonstrated the highest regeneration (90%) and most significant difference (p < 0.01) compared to the untreated control. ConclusionThe results revealed that the five Bulbine species have complex chemical profiles, however, they share major compound classes (i.e. phenylanthroquinones and flavonoid analogues) across the species. The study highlights the wound-healing properties of the five species, which is consistent with their traditional use.

High-throughput LC-PDA method for determination of Δ9-THC and related cannabinoids in Cannabis sativa

Before the passage of the Agriculture Improvement Act of 2018, more commonly referred to as the 2018 Farm Bill, forensic laboratories were only required to perform qualitative measurements to confirm the identity of seized plant samples as Cannabis sativa (hemp or marijuana). The new law defines hemp at a federal level as Cannabis sativa containing 0.3 % or less Δ9-THC. Because forensic laboratories were not adequately equipped with the proper methods or training to meet these requirements, significant backlogs in casework resulted. The National Institute of Standards and Technology (NIST) responded by providing analytical tools to the forensic community. An accurate and precise method was previously developed to determine Δ9-THC, Δ9-THCA, and total Δ9-THC in botanical samples based on liquid chromatography with photodiode array detection (LC-PDA). Cannabis plant samples were ground and extracted with methanol using routine laboratory equipment. The original sample preparation procedure was time-consuming, taking over 70 min. The method described here has been optimized with the time required for sample preparation and LC-PDA analysis has been reduced to less than 30 min.

Comparison of piperine content, antimicrobial and antioxidant activity of Piper chaba root and stem

Piper chaba (locally known as “Choi Jhal”) is used traditionally as spices and folk medicine in different parts of Bangladesh. One of the most important bioactive compounds in this plant is piperine. In this study, the amount of piperine in P. chaba root and stem was investigated and the optimal solvent for piperine extraction at room temperature was also studied. High performance liquid chromatography (HPLC) was operated using a reverse phase column where methanol and water (70:30) were used as mobile phase. The detection was performed using photo diode array (PID) detector at a wavelength of 345 nm. The standard piperine showed linearity between 0.005 % and 0.04 % and the correlation co-efficient found for the linearity was 0.9933. The percentage of relative standard deviation (RSD) for both retention time and peak area were less than 2.0 %. The theoretical plate number (N) > 3000 and a tailing factor (T) < 1.5 were found in the acceptable range. The recovery percentage (%) of standard piperine was 99.16 %. Low value of co-efficient of variation and standard deviation are recognized for high precision of the method. The highest amount of piperine was found in root extracted with methanol (MR) amounting to 1.75 % in the root powder. The maximum amount of piperine in the stem was 1.59 % when extracted with methanol (MS). The piperine quantification in other extract like n-hexane root (HR), ethyl acetate root (ER), n-hexane stem (HS), ethyl acetate stem (ES) were 0.76 %, 1.69 %, 0.33 % and 1.46 % respectively. Methanol has given the highest yield of piperine compared to ethyl acetate and n-hexane for both root and stem. The developed method was simple, rapid, economic and validated in terms precision, accuracy and recovery. This selective method is found to be repeatable, accurate and successfully utilized for the Piper extract in marketed and pharmaceutical samples with well chromatographic conditions. The ethyl acetate extract of root and stem showed promising DPPH (1, 1-diphenyl-2-picrylhydrazyl) free radical scavenging activity with an IC50 value of 39.62 ± 0.95 μg/mL and 43.85 ± 1.50 μg/mL respectively. The study reports potential antibacterial activity and antifungal activity of P. chaba root and stem extracts. These outcomes revealed that different extracts of P. chaba may be used as natural preservatives.

Simultaneous determination of acid carnosic and carnosol in rosemary-containing foods by high-performance liquid chromatography with photodiode array detection (HPLC–PDA)

The research was conducted to develop and validate a simultaneous quantification method for acid carnosic (CA) and carnosol (CAR) in rosemary-containing foods using highperformance liquid chromatography coupled with photodiode array detection (HPLC&amp;ndash;PDA), with a simple and fast sample processing procedure. Analytical samples were extracted using a methanol&amp;ndash;phosphoric acid mixture (99.5:0.5, v/v) at room temperature for 20 minutes. The chromatographic conditions were as follows: Sunfire C18 column (4.6 mm x 250 mm; 5 &amp;micro;m), mobile phase consisting of 0.1% phosphoric acid &amp;ndash; acetonitrile (40:60, v/v), flow rate of 1 mL/min, injection volume of 10 &amp;micro;L, detection at 230 nm. The method was validated according to the Association of Official Analytical Chemists (AOAC) criteria. The results showed that the method had good specificity, and the standard curves of acid carnosic and carnosol were linear in the concentration range of 2.5 &amp;ndash; 200 &amp;micro;g/mL. The limits of detection (LOD) for acid carnosic and carnosol were 0.3 &amp;micro;g/mL and 0.25 &amp;micro;g/mL, respectively. The limits of quantification (LOQ) for acid carnosic and carnosol were 1 &amp;micro;g/mL and 0.75 &amp;micro;g/mL, respectively. The recovery rates were in the range of 98.8 &amp;ndash; 100.6% (acid carnosic) and 97.5 &amp;ndash; 102.2% (carnosol). Repeatability and internal reproducibility met the requirements of AOAC. The method was applied to evaluate the acid carnosic and carnosol levels in 20 food samples collected from the market, such as rosemary leaf powder, dried rosemary leaves, rosemary herbal tea,...

UPLC-PDA factorial design assisted method for simultaneous determination of oseltamivir, dexamethasone, and remdesivir in human plasma

A green and simple UPLC method was developed and optimized, adopting a factorial design for simultaneous determination of oseltamivir phosphate and remdesivir with dexamethasone as a co-administered drug in human plasma and using daclatasvir dihydrochloride as an internal standard within 5 min. The separation was established on UPLC column BEH C18 1.7 μm (2.1 ×\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\ imes $$\\end{document} 100.0 mm) connected to UPLC pre-column BEH 1.7 μm (2.1 ×\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\ imes $$\\end{document} 5.0 mm) at 50 °C with an injection volume of 10 μL. The photodiode array detector (PDA) was set at three wavelengths of 220, 315, and 245 nm for oseltamivir phosphate, the internal standard, and both dexamethasone and remdesivir, respectively. The mobile phase consisted of methanol and ammonium acetate solution (40 mM) adjusted to pH 4 in a ratio of 61.5:38.5 (v/v) with a flow rate of 0.25 mL min−1. The calibration curves were linear over 500.0–5000.0 ng mL−1 for oseltamivir phosphate, over 10.0–500.0 ng mL−1 and 500.0–5000.0 ng mL−1 for dexamethasone, and over 20.0–500 ng mL−1 and 500.0–5000.0 ng mL−1 for remdesivir. The Gibbs free energy and Van't Hoff plots were used to investigate the effect of column oven temperatures on retention times. Fluoride-EDTA anticoagulant showed inhibition activity on the esterase enzyme in plasma. The proposed method was validated according to the M10 ICH, FDA, and EMA’s bioanalytical guidelines. According to Eco-score, GAPI, and AGREE criteria, the proposed method was considered acceptable green.

Metabolomics and quantitative analysis to determine differences in the geographical origins and species of Chinese dragon's blood.

The aim of this study was to comprehensively analyze the differences in Chinese dragon's blood (CDB), specifically Dracaena cochinchinensis and Dracaena cambodiana, from different geographical origins. Metabolomic analysis of CDB was performed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). A reliable ultrahigh-performance liquid chromatography method with a photodiode array detector (UHPLC-PDA) was developed and applied for the quantitative analysis of 12 phenolic compounds in 51 batches of samples. A total of 1394 metabolites were detected, of which 467 were identified as differentially accumulated metabolites. Multivariate analysis revealed that both origin and species had an effect on the composition of CDB, with greater variation between species. 19 phenolic compounds were selected as quality markers to distinguish D. cochinchinensis (Hdsp) from D. cambodiana (Hdca), and oppositin and spinoflavanone a were identified as quality markers to discriminate D. cochinchinensis samples from Hainan (Hdsp) and Guangxi Provinces (Gdc). Quantitative analysis indicated that four phenolic compounds, including loureirin D, 4H-1-benzopyran-4-one,2,3-dihydro-3,5,7-trihydroxy-3-[(4-methoxyphenyl)methyl]-,(R)-, loureirin B, and pterostilbene, showed significant differences between Gdc and Hdsp. Additionally, five phenolic compounds, namely resveratrol, loureirin D, pinostilbene, 4H-1-benzopyran-4-one,2,3-dihydro-3,5,7-trihydroxy-3-[(4-methoxyphenyl)methyl]-, (R)-, and loureirin B, exhibited significant differences between Hdsp and Hdca. There are significant differences in the quality of CDB from different geographical origins and species, which lays the foundation for the in-depth development and utilization of different sources of CDB.

Characterization, quantitation, and natural variability of phenolics in Rhododendron arboreum leaves of western Himalayan origin using UPLC-PDA and UHPLC-ESI-Q/TOF-MS/MS

Rhododendron arboreum Sm. is very popular in the Indian Himalayan region due to its significant ethnomedicinal importance and potential commercial applications. Apart from the ornamental value derived from its vibrant red flowers, fresh flowers are used to prepare medicinal juices, and dried are utilized as spices. Despite being a rich source of phenolics, these lack identified marker chemicals and validated methods. The present work encompasses the chemical investigation of R. arboreum leaves using UHPLC-ESI-Q/TOF-MS/MS. The chemotypic variability was assessed through a reverse phase ultra-performance liquid chromatography method coupled with a photodiode array detector (RP-UPLC-PDA) chemical signatures of R. arboreum leaves from different altitudes combined with chemometric analysis. The chromatographic method was developed and validated for the quantitative analysis of three vital secondary metabolites, i.e., Isoquercetin or Quercetin-3-O-glucoside (Qg), Reynoutrin or Quercetin-3-O-xyloside (Qx), and Quercitrin or Quercetin-3-O-rhamnoside (Qr)The hyphenation of the method with ESI-Q/TOF-MS/MS has confirmed the distribution of 11 chemicals (nine known and two unknown) in R. arboreum leaves belonging to the phenolic and hydrolyzable tannins class. Samples from higher altitudes >3000 m (above mean sea level) were exceptionally rich in Quercitrin. The chemometric investigation, comprising hierarchical cluster analysis (HCA), principal component analysis (PCA), and partial least square method-discriminant analysis (PLS-DA), successfully categorized thirty-three samples from diverse geographic regions into two distinct categories. This current study provides a validated method for the chemotypic discrimination and quality assessment of the R. arboreum leaves from Uttarakhand, Western Himalayan region of India, and laid the foundation for the comprehensive utilization of these renewable and sustainable resources.

HPLC-PDA Analysis of Polyacetylene Glucosides from Launaea capitata and Their Antibacterial and Antibiofilm Properties against Klebsiella pneumoniae.

Background/Objectives: Bacterial resistance and virulence are challenges in treating bacterial infections, especially in Klebsiella pneumoniae. Plants of the Launaea Cass. genus are used traditionally to address a variety of diseases, including infections, but the potential bioactive compounds are unknown. Our goals were to verify the potential contribution of two major polyacetylene glycosides isolated from our previous study, (3S,6E,12E)-6,12-tetradecadiene-8,10-diyne-1-ol 3-O-β-D-glucopyranoside (1) and bidensyneoside A (syn. gymnasterkoreaside A) [(3R,8E)-3-hydroxy-8-decene-4,6-diyn-1-yl β-D-glucopyranoside] (2), to the anti-infective properties of Launaea capitata and to develop a dependable HPLC method for their quantification; Methods: On a panel of K. pneumoniae clinical isolates, the antibacterial action of 1, 2, and the methanol extract of the whole L. capitata plant were evaluated by broth microdilution assay, while their antibiofilm action was evaluated by the crystal violet assay. qRT-PCR investigated luxS, mrkA, wzm, and wbbm genes that encode biofilm formation and quorum sensing (QS). The antibacterial activity of 1 was revealed by employing mice infection. Chromatographic separation was conducted using isocratic elution on a Hypersil BDS C18 column using a photodiode array (PDA) detector; Results: Compound 1 showed antibacterial activity with MIC values of 16-128 µg/mL. It remarkably reduced strong and moderate biofilm-forming bacterial isolates from 84.21% to 42.1% compared with the extract (68.42%) and 2 (78.95%). Compound 1 also downregulated the QS genes, luxS, mrkA, wzm, and wbbm, and exhibited in vivo antibacterial action through the enhancement of the histological construction of the liver and spleen, decreased TNF-α immunoreaction, bacterial burden, and the inflammatory mediators IL-1β and IL-6. A successful HPLC-PDA approach was developed to separate the binary mixture of 1 and 2 in less than 10 min with high sensitivity, with detection limits down to 0.518 and 0.095 µg/mL for 1 and 2, respectively; Conclusions: Compound 1 exhibited remarkable antibacterial and antibiofilm properties and may contribute to the anti-infectious traditional uses of L. capitata, meriting further clinical studies and serving as a reliable quality control biomarker for the plant.

Innovative UPLC technique for concurrent quantification of etofenamate and benzyl nicotinate in the presence of methylparaben and benzyl alcohol in their topical cream: Greens, white, and Six Sigma methodologies.

The efficacious treatment of muscle and joint pain relies heavily on etofenamate (ETO) and benzyl nicotinate (BN), which possess robust anti-inflammatory and pain-relieving properties when paired with methylparaben (MP) or benzyl alcohol (BA). In this study, we have established and validated innovative RP-UPLC methods for assessing ETO and BN in the presence of MP or BA in their dosage forms, employing eight green tools to evaluate their eco-friendliness and effectiveness. Reversed phase-ultra-performance liquid chromatography (RP-UPLC) technique employs a flow rate of 0.3mL/min on Waters Acquity UPLC BEH Column (C18, 1.7μm, 100 mm × 2.1mm), detection at 254 nm using a photo diode array (PDA) detector and mobile phase of 0.05 M KH2PO4 buffer, acetonitrile, and methanol (50:15:35, v/v/v) adjusted pH6.0 with 0.2% triethylamine. For ETO, BN, MP, and BA, the calibration curves were linear and ranged from 0.005 to 1.0, from 0.001 to 0.2, from 0.002 to 0.08, and from 0.0001 to 0.1mg/mL, respectively. The correlation value was 0.9999, and the accuracy findings ranged from 98.81% to 100.56%. Consequently, the methodology has been successfully implemented in assay testing for the pharmaceuticals in the presence of the MP or BA, demonstrating the high selectivity of these approaches. The present study presents the Blue Applicability Grade Index (BAGI), an innovative approach that complements green metrics in practical white analytical chemistry. According to the International Council for Harmonisation (ICH) criteria, the procedures were effectively validated.

A New Highly Effective Development and Validation of Trastuzumab and Hyaluronidase-Oysk in Bulk and Pharmaceutical Dosage form by Using RP-HPLC Method

A simple, rapid, precise, sensitive, and reproducible Reverse phase High-performance liquid chromatography (RP-HPLC) method has been developed for the quantitative analysis of Trastuzumab and Hyaluronidase-OYSK in the pharmaceutical dosage form. Chromatographic separation of Trastuzumab and Hyaluronidase-OYSK was achieved on Waters Alliance-e2695by using Agilent Eclipse XDB (250x 4.6mm, 5µ) column and the mobile phase containing Acetonitrile: Ammonium formate pH-3.0/OPA in the ratio of 30:70% v/v. The flow rate was 1.0 ml/min; detection was carried out by absorption at 228nm using a photodiode array detector at ambient temperature. The number of theoretical plates and tailing factor for Trastuzumab and Hyaluronidase-OYSK were NLT 2000 and should not be more than 2 respectively. % Relative standard deviation of peak areas of all measurements always less than 2.0. The proposed method was validated according to ICH guidelines. The method was found to be simple, economical, suitable, precise, accurate &amp; robust method for quantitative analysis of Trastuzumab and Hyaluronidase-OYSK study of its stability.

Analytical quality by design-based stability-indicating high performance liquid chromatography method for the estimation of evogliptin tartrate in bulk and tablet dosage form.

The present study utilized Analytical Quality by Design (AQbD) approach to develop a stability-indicating high-performance liquid chromatography (HPLC) method for estimating evogliptin tartrate using design expert software. The key parameters were methodically optimized, contours were plotted, and stability was evaluated using various forced degradation conditions. Using an Agilent HPLC system with a photo diode array (PDA) detector along with Fortis C18 column (250 × 4.6mm, 5μm) effectively separated the drug from its degradants. The mobile phase used was methanol: water (pH adjusted to 3.0, 76:24; v/v) at 0.8mL/min flow rate. Evogliptin was eluted at 2.98 min, at a detection wavelength of 267 nm. The proposed method was found to be specific, precise, linear and robust. The drug was sensitive to acidic, basic, oxidative, thermal, and photodegradation resolving six degradation products. Thus, the developed AQbD-based stability-indicating HPLC method is applicable in analyzing evogliptin in bulk, tablet dosage form and stability samples.

Pharmacokinetic Pattern of Menbutone in Calves after Single Intravenous and Intramuscular Administration.

Menbutone is a choleretic agent currently used in Europe to treat digestive disorders in livestock and dogs. Pharmacokinetic parameters were established in 4-month Holstein calves after intravenous (IV) and intramuscular (IM) administration. The drug was administered to 12 animals (10 mg/kg) for both IV and IM routes following a crossover design. Plasma samples were collected at various time points over 24 h and analyzed by reverse-phase high-performance liquid chromatography with a photodiode-array detector, following a method validated according to European Medicines Agency guidelines. Pharmacokinetic parameters were calculated using compartmental and non-compartmental methods. Menbutone followed a two-compartment open model after IV injection, with a total clearance (Cl) of 71.9 ± 13.5 mL/h/kg, an elimination half-life (t½β) of 4.53 ± 2.45 h, and a volume of distribution at steady-state (Vss) of 310.4 ± 106.4 mL/kg. Non-compartmental elimination half-life (t½λ) was 4.2 ± 1.1 h. After IM administration, drug pharmacokinetics was best described by a one-compartment open model. The peak plasma concentration (Cmax) was 15.1 ± 4.3 µg/mL; the time to reach Cmax (tmax), 1.66 ± 0.55 h; and the mean absorption time (MAT), 2.50 ± 1.42 h. Absorption was high, with a fraction of the dose absorbed (F) of 83.5 ± 22.4%. Menbutone was rapidly eliminated from plasma for both routes of administration, with a fast and high IM bioavailability.