Method For Routine Analysis Research Articles

Development and validation of an LC-MS/MS method for quantification of Osimertinib and its two metabolites AZ7550 and AZ5104 in human plasma including long-time storage.

Osimertinib (AZD9291) is a widely used tyrosine kinase inhibitor for the treatment of non-small cell lung cancer patients with activating EGFR mutations. However, the correlation between dose and efficacy has been debated for several years. For this reason, there is a need for standardized methods for routine analysis, clinical studies on pharmacokinetics and dose-response relationships, and greater understanding of preanalytical conditions, such as sample storage stability. The objective of this study was to develop and validate a sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for simultaneous quantification of osimertinib and its two metabolites, AZ7550 and AZ5104, in human plasma and to investigate long-term storage stability of the analytes. Samples were prepared by protein precipitation and separated on a Kinetex EVO C18 column (2.1 × 150 mm, 2.6 µm). Electrospray ionization in positive mode and multiple reaction monitoring were used to monitor the ion transitions. The validated concentration ranges were from 1.25 to 3000 ng/mL. Interassay precisions and accuracies were all ≤ 15 %. Linearity, dilution integrity, and carry-over were also examined and satisfied the validation criteria. Stability was examined under different conditions, and the analytes were found to be stable for more than 3 years at -80°C (< 15 % decline). Finally, the analytical method was successfully applied in a clinical setting on plasma samples from 30 patients with non-small cell lung cancer in treatment with osimertinib, demonstrating its suitability for use in clinical studies and its potential for therapeutic drug monitoring.

Comparative validation of UV-spectrophotometry and RP-HPLC methods for cefixime and moxifloxacin analysis

AimThis study presents the development and validation of UV-spectrophotometry and RP-HPLC methods for the simultaneous quantification of Cefixime Trihydrate (CEFI) and Moxifloxacin Hydrochloride (MOXI) in pharmaceutical formulations. MethodologyTwo UV-spectrophotometric methods, including the absorbance ratio (Q-Absorption) and First Order Derivative Spectroscopy, were developed and validated for their linearity, precision, accuracy, and sensitivity. Additionally, a robust RP-HPLC method using a C18 column and optimized mobile phase was employed for efficient separation and simultaneous estimation of CEFI and MOXI. All methods were validated in accordance with ICH guidelines, with system suitability parameters confirming the reliability of the RP-HPLC method for routine analysis. ResultsThe absorbance ratio and First Order Derivative methods demonstrated low %R.S.D values, high accuracy, and satisfactory sensitivity for both drugs. Similarly, the RP-HPLC method achieved high resolution, precision, and robustness. Statistical analysis through ANOVA revealed no significant differences between the methods in terms of accuracy and precision. The methods were applied to analyze marketed formulations, further confirming their applicability in routine quality control. ConclusionIn conclusion, the validated methods provide accurate, precise, and sensitive techniques for the simultaneous estimation of CEFI and MOXI, making them suitable for pharmaceutical quality control and regulatory compliance.

Application of GO@ZIF-8 MOF/molecularly imprinted polymer composite for multiple monolithic fiber solid phase microextraction: Determination of illegally added amphetamines in snacks and beverages and quantitation by GC-MS

Some adulterated products are marketed to promote weight loss, increase energy or cognition, build muscle, or promote athletic and sexual performance. They may contain undisclosed or mislabeled substances. In this study, a new method for the determination of amphetamine derivatives illegally added to beverages and snacks using a GO@ZIF-8 MOF fiber combined with molecularly imprinted polymer (MIP)/solid-phase microextraction (SPME), followed by gas chromatography-mass spectrometry (GC-MS) analysis is presented. The prepared fiber is characterized by Fourier-transform infrared (FT-IR), X-ray powder diffraction (XRD), and scanning electronic microscope (SEM) techniques. Following optimization of the extraction factors, a linear range between 0.1 and 400 μg L−1 with a coefficient of determination (R2) exceeding 0.9976 was achieved for the specified compounds. Detection limits for amphetamine derivatives were found to be between 0.023 and 0.033 μg L−1. The limits of detection were found to comply with regulatory limits, indicating the sensitivity of the method for routine analysis. This method was effectively utilized to quantify amphetamine derivatives in snakes and beverages samples. The recovery rate exceeded 96.2 %, and the error under 6.7 %, demonstrating the reliability of method. No significant interference from sample matrix components was observed, demonstrating the selectivity of the method.

Fabrication of high performance 2D flexible SERS substrate based on cellulose nanofibrils and its application for pesticide residue detection

Cellulose nanofibrils (CNFs) can serve as an efficient surface enhanced Raman scattering (SERS) platform for in situ detection of trace targets. In this study, a highly reproducible SERS platform based on TEMPO-oxidized CNFs (T-CNFs) was fabricated by the ion-exchange. Self-assembly of silver nanoparticles (AgNPs) was accomplished in only 120 s. The abundant carboxylate groups and good hydrophilicity of T-CNFs facilitated uniform and dense loading of AgNPs over the surface area. The obtained SERS substrate greatly enhanced the Raman signal of different pesticides, and the detection limits of thiram and thiabendazole were 5.81 × 10−8 M and 9.63 × 10−8 M, respectively. SERS substrate could produce homogeneous Raman-enhanced signals (relative standard deviation (RSD) = 6.59 %). In addition, due to the good flexibility, SERS substrate could collect and detect pesticide residues from the surface of apples. The intensities of Raman characteristic peak at 1384 cm−1 showed a good linear relationship with the analyte concentrations (0.96 ng/cm2–9600 ng/cm2). The constructed SERS substrate provided a theoretical basis for the preliminary rapid screening of hazardous chemical residues in food, which was of great value for the SERS technique to become a routine on-site analysis method for pesticide residues.

Scientifc Validation and Chromatographic Method Development for the Estimation of Piperine in Herbal Formulation Babbularishta: A Quality Control Strategy for Critical Quality Attributes

Background: Babbularishta is an Ayurvedic medicine in liquid form used for the treatment of phthisis, skin diseases, urinary disorders,, and breathing problems. It is also beneficial in cases of blood disorders, acne, dermatitis, hemoptysis, lung injury, asthma, persistent cough, whooping cough, etc. Objective: The functional role of this study is to develop a simple, novel, precise, accurate, reliable, and selective RP-HPLC method for the estimation of piperine content in herbal drug formulations (Babbularista). Methods: A traditional approach to method development could fail to meet the desired separation. Consideration of the current regulatory requirement for analytical method development and RP-HPLC method for routine analysis of piperine in the herbal formulation has been optimized using an analytical Quality by Design (QbD) approach. Three laboratory formulations and three marketed preparations of Babularishta were investigated for organoleptic parameters, physicochemical parameters, and validation. The mobile phase composition (methanol and water % as A), pH (B), and flow rate (mL/min as C) were selected as independent variable,. In contrast, retention time (min. as Y2), area (AU as Y1) is selected as dependent variables. Results: The fingerprinting method was developed and optimized by using the AQbD approach. Piperine content was found to be in Piper nigrum (Marica) 3.01±0.01527 % w/w and in Piper longum (Pipali) 2.74±0.01154% w/w in Babbularista. Conclusion: An attempt has been made to develop quality control parameters of Babbularista by developing a suitable and sensitive HPLC methods for the quantitation of piperine in herbal drug formulations (Babbularista). The developed method was found to be simple, accurate, precise,, and economical for the estimation of piperine in herbal formulations.

Improvements and Heterogeneities of the Global Centroid Moment Tensor Catalog

Abstract Earthquake catalogs are heterogeneous, especially those developed over long time spans. Changes in seismological monitoring, which provides the records on which these catalogs are based, are common. Typically, instruments and networks become more sensitive over time, allowing for the detection and characterization of smaller earthquakes. In pursuit of improvement, new methods for routine data analysis are occasionally introduced, modifying the procedures for catalog compilation. The resulting heterogeneities may not be evident to users, but they should be unveiled and considered in any application of the catalog, especially in statistical seismology, which analyzes large earthquake data sets. The Global Centroid Moment Tensor catalog is considered the most homogeneous database of global seismicity. However, a detailed analysis of its heterogeneities has been lacking. This work reviews changes in the catalog’s development from 1976 to 2023 and reveals how these have caused improvements and heterogeneities in the resulting data. Several periods are distinguished, separated by milestones in the methods employed for moment tensor inversion and catalog compilation, as well as by the advent of global broadband monitoring in 2004. These changes are shown to have caused variations in the catalog’s completeness and in the determinations of centroid depths, scalar seismic moments, and moment tensors. The magnitude of completeness is measured here in detail, both temporally and spatially. It has decreased over the years and shows spatial variations within each period, correlated to regional differences in network monitoring and compilation biases. Moment tensor determinations have been significantly different since 2004, resulting in a different frequency distribution of rake angles and a different dependence of the double-couple component as a function of rake. This work is expected to benefit all future uses of the catalog, enabling better characterization of seismicity properties and improved building and testing of models for earthquake occurrence.

Advancing Bioanalytical Method Validation: A Comprehensive ICH M10 Approach for Validating LC-MS/MS to Quantify Fluoxetine in Human Plasma and Its Application in Pharmacokinetic Studies.

A fast and sample cleanup approach for fluoxetine in human plasma was developed using protein precipitation coupled with LC-MS-MS. Samples were treated with methanol prior to LC-MS-MS analysis. Chromatographic separation was performed on a reverse phase column with an isocratic mobile phase of methanol and 10 mM ammonium formate pH acidified with formic acid (80:20, v/v) at a flow rate of 0.2 mL/min. The run time was 4 min. Mass parameters were optimized to monitor transitions at m/z [M + H]+ 310 > > 148 for fluoxetine and m/z [M + H]+ 315.1 > > 153 for fluoxetine-d5 as an internal standard. The lower limit of quantification and the dynamic range were 0.25 and 0.25-50 ng/mL, respectively. Linearity was good for intra-day and inter-day validations (R2 = 0.999). The matrix effect was acceptable with CV% < 15 and accuracy% < 15. The hemolytic effect was negligible. Fluoxetine was stable in human plasma for 48 h at room temperature (25 °C), for 12 months frozen at -25 °C, for 48 h in an auto-sampler at 6 °C, and for three freeze/thaw cycles. The validated method was applied in a pharmacokinetic study to determine the concentration of fluoxetine in plasma samples. The study provides a fast and simple bioanalytical method for routine analysis and may be particularly useful for bioequivalence studies. The method was successfully applied to a pharmacokinetic study of fixed-dose fluoxetine in nine healthy volunteers.

A practical HPLC-MS method for the analysis of nitrosamine drug substance related impurities using an inexpensive single quadrupole mass spectrometer

Nitrosamine drug substance related impurities (NDSRIs) are often analyzed using high performance liquid chromatography (HPLC) with mass spectrometry (MS) detection. Due to high sensitivity requirements, high resolution MS or MS/MS is commonly used. However, it is difficult to implement this type of method for routine analysis at a supply site. Herein, we report a systematic approach to develop and validate a practical, robust, and user-friendly method for the analysis of NDSRIs using an inexpensive single quadrupole MS instrument such as QDa. We used 7-nitroso-3-(trifluoromethyl)-5,6,7,8-tetrahydro- [1,2,4] triazolo [4,3-a] pyrazine (NTTP) as an example to demonstrate the method development process. By optimizing the HPLC and MS parameters, we were able to develop a simple HPLC-MS method that provides the desired specificity and sensitivity for the analysis of NTTP and can be easily implemented in an analytical lab. The limit of quantitation is 0.5 ng/mL, corresponding to 0.1 ppm with respect to 5 mg/mL sitagliptin. The method has been successfully validated per ICH guidelines.

Rapid UV-Vis spectrophotometric method aided by firefly-PLS models for the simultaneous quantification of ciprofloxacin, lomefloxacin, and enrofloxacin in their laboratory mixture, dosage forms and water samples: greenness and blueness assessment

Herein, a novel UV spectrophotometric method coupled with chemometric tools was developed for the simultaneous determination of three fluoroquinolone antibiotics: ciprofloxacin, lomefloxacin, and enrofloxacin. Such integration of UV spectroscopy and chemometric analysis proved to be a simple, rapid, and cost-effective approach for the quantification of these clinically important pharmaceutical compounds and aid in their quality control analysis. The method employed firefly algorithm for variable selection and partial least squares (PLS) regression for model calibration. The developed method was validated by independent test set in addition the accuracy, intra and inter-day precision as per ICH guidelines which showed a satisfactory performance with mean recovery ranged between 98.18 and 101.83 with %RSD < 2. Besides, the developed method displayed ultrasensitive levels with LODs (0.0803, 0.1125, 0.1309 µg/mL) and LOQs (0.2434, 0.3409, 0.3968 µg/mL) for ciprofloxacin, lomefloxacin, and enrofloxacin, respectively. The greenness and blueness of the developed method were also evaluated using the recently proposed Analytical GREEnness metric approach (AGREE) and Blue applicability grade index (BAGI) tools, which showed a high AGREE score of 0.79 and a BAGI score of 77.5. These results indicate that the developed method provides an environmentally friendly alternative to the traditionally used chromatographic techniques, while maintaining high analytical practicability. Finally, the application of the developed methodology was demonstrated on real pharmaceutical and tap water samples, and the results were in good agreement with those obtained by the reference HPLC method indicating the reliability and suitability of the proposed spectrophotometric method for routine analysis of fluoroquinolone antibiotics.

ESTIMATION OF TENOFOVIR BY UV VISIBLE SPECTROSCOPY

In view of the need for a suitable Spectroscopic method for routine analysis of Tenofovir(antiretroviral medicine) in formulations, attempts were made to develop simple, precise and accurate analytical method for estimation of Tenofovir in formulation. As Validation is a necessary and important step in both framing and documenting the capabilities of the developed method it was done in accordance with USP and ICH guideline for the assay of active ingredient. The method was validated for parameters like linearity, precision, accuracy, specificity, and robustness, limit of detection and limit of quantification. This method provides means to quantify the component. This proposed method was suitable for the analysis of Pharmaceutical dosage forms.The utility of the developed method to determine the content of drug in commercial formulation was also demonstrated. KEY WORDS: Tinofovir,Validation,UV Visible spectroscopy.

Direct Determination of Glyphosate and Its Metabolites in Foods of Animal Origin by Liquid Chromatography-Tandem Mass Spectrometry.

Glyphosate is the most used herbicide in agriculture. Its major metabolite is AMPA (aminomethylphosphonic acid), but N-acetyl-AMPA and N-acetylglyphosate are also metabolites of interest. For risk assessment, a general residue definition was proposed as the sum of glyphosate, AMPA, N-acetyl-glyphosate and N-acetyl-AMPA, expressed as glyphosate. A confirmatory method for glyphosate in fat, liver and kidneys, as well as a confirmatory method for AMPA and N-acetyl-glyphosate in all matrices, are still missing. In this paper, we present a method for the quantitative determination of glyphosate residues and its metabolites AMPA, N-acetyl-AMPA and N-acetyl-glyphosate by liquid chromatography-mass spectrometry (LC-MS/MS) in adipose tissue, liver, eggs, milk and honey without derivatization. Different chromatographic columns were tested, with the Hypercarb column providing the best results. The analytes were eluted with mobile phases of acidified water with 1.2% formic acid and 0.5% formic acid in acetonitrile. Sample purification procedures were also optimized by varying the solvent extraction mixtures (water, methanol and mixture ψ (methanol, water) = 1:1, each with the addition of 1% formic acid (v/v)), using different sorbents in solid phase extraction (SPE) (polymeric cationic (PCX) and anionic (PAX)) and using dispersive solid phase extraction (dSPE) (C18 and PSA) by modifying the extraction procedures. Finally, the analytes were extracted from the samples with 1% formic acid in water (v/v). Milk and adipose tissue were purified by the addition of dichloromethane, while liver and egg samples were purified by SPE with a mixed cation exchange sorbent and ultrafiltration with cut-off filters. The proposed analytical procedures were validated according to SANTE/11312/2021 guidelines: linearity, limits of quantification, precision and accuracy were determined for all matrices. The limits of quantification (LOQs) ranged from 0.025 to 0.2 mg kg-1. Precision, expressed as relative standard deviation, was <20%, while accuracy, expressed as analytical recovery, ranged from 70% to 120%. During method validation, the measurement uncertainty was estimated to be <50% for all analytes. Good validation parameters according to the SANTE document were achieved for all analytes. Therefore, the method can be considered reliable and sensitive enough for routine monitoring of polar pesticides. The application of the accredited method in routine analysis will provide data that are useful for the re-evaluation of risk assessment studies in foods of animal origin.

Automation and standardisation of a quantitative multiplex PCR assay using PCR.Ai

BackgroundWe previously undertook a prospective clinical study to evaluate PCR.Ai’s (www.pcr.ai) accuracy and impact when automating the manual data-analysis and quality control steps associated with routine clinical pathogen testing using a non-quantitative multiplex quantitative real-time PCR (qPCR). In this study we demonstrated 100 % concurrence between our manual routine analysis method and PCR.Ai. This paper expands the evaluation of PCR.Ai’s (www.pcr.ai) accuracy and impact using a multiplex quantitative real-time PCR (qPCR). ObjectivesWe evaluated the impact of PCR.Ai when used as the final interpretation/verification step for routine in-house multiplex quantitative qPCR tests for CMV, EBV and adenovirus from blood samples for a total of 1350 interpretations. Study DesignWe compared PCR.Ai to our existing manual interpretation, to determine accuracy and hands on time savings. Results and ConclusionsThere was 100 % concurrence between validated CMV, EBV and adenovirus detection and quantitation by our manual routine analysis method and PCR.Ai. Furthermore, there were significant routine savings with PCR.Ai of 63 minutes/ run. Our conclusion is that for quantitative tests PCR.Ai is a highly accurate time-saving tool that reduces complexity of qPCR analysis and hence the need for specialists and hands-on time. It demonstrated capabilities to enable us to get results out more quickly with lower costs and less risk of errors.

Development of recombinant adeno-associated virus empty capsids as a reference standard for quality control of gene therapy products

INTRODUCTION. The development of adeno-associated virus (AAV)-based gene therapy products in Russia requires establishing reference standards, which are used throughout the pharmaceutical development cycle, and monitoring their stability during the storage period. A preparation of empty capsids of AAV serotype 9 (AAV9) is an appropriate material for a reference standard for empty AAV9 capsids (AAV9 RS).AIM. This study aimed to develop analytical procedures to evaluate the AAV9 RS physicochemical quality parameters for its characterisation and to study its storage stability.MATERIALS AND METHODS. Empty AAV9 capsids were produced in HEK293 suspension culture using serum-free medium and optimised transfection parameters. The next steps involved AAV9 clarification, concentration, and purification by affinity chromatography with AAVx resin and diafiltration. The analysis of AAV9 samples used electrophoresis, transmission electron microscopy, enzyme-linked immunosorbent assay (ELISA), size-exclusion chromatography, dynamic light scattering, spectrophotometry, and bio-layer interferometry. The concentration of capsids was measured by ELISA. Analytical procedures for physical titre determination were developed using an AAV9 standard with a known physical titre. The stability study of the AAV9 RS involved storage at –80 °C for 9 months.RESULTS. Size-exclusion chromatography demonstrated the high purity of the established AAV9 RS, with at least 98% content of the viral capsid monomer. Dynamic light scattering, size-exclusion chromatography, and electron microscopy confirmed that the AAV9 RS was free of aggregates. The stability study showed that the AAV9 RS remained stable for 9 months. Dynamic light scattering and spectrophotometry were deemed optimal methods for routine quality analysis measuring the AAV9 RS physical titre, and bio-layer interferometry was recommended for regular analysis. The viral particle titres determined by these methods ranged from 1.48×1013 to 5.6×1013.CONCLUSIONS. The AAV9 RS established in this study is suitable for quality control of AAV9-based gene therapy products.

Development and validation of a multi-substance method for routine analysis of pesticides in post-mortem samples by Ultra-High Performance Liquid Chromatography-Tandem Mass Spectrometry

Pesticides play an important role in forensic toxicology and are usually classified as a single class of chemicals. Despite their commonly perceived unity, pesticides encompass a spectrum of compounds, including organophosphates, carbamates, pyrethroids or organochlorines, among others, each with varying degrees of toxicity. Pesticide analysis in post-mortem samples can be difficult due to the complexity of the samples and to the high toxicity of these compounds. The aim of this study was to develop and validate an easy to use, sensitive, and robust method, using ultra-performance liquid chromatography-tandem mass spectrometry to be incorporated in the routine flow for pesticide analysis in post-mortem blood samples. Described herein is a streamlined, expeditious, yet highly efficient method facilitating the screening, qualitative assessment, and quantitative confirmation of 15 pesticides, including acetamiprid, azinphos-ethyl, bendiocarb, carbofuran, chlorfenvinphos, dimethoate, imidaclopride, malathion, methiocarb, methomyl, parathion, pirimicarb, strychnine, tetrachlorvinphos, and thiacloprid in post-mortem blood, recognizing the pivotal role blood plays in forensic investigations. The developed method was linear from 10 to 200 ng/mL; limits of detection were between 1 and 10 ng/mL, depending on the compound; it was successfully evaluated a dilution ratio of 1–2, 5 and 10; and 8 substances showed maximum stability for the time interval studied. This UHPLC-MS/MS method is useful and a powerful tool in a toxicology lab because it is fast, simple, effective, and trustworthy. The results of this validation highlight the robustness of the analytical method, providing a valuable tool for the accurate and sensitive detection of pesticides in post-mortem blood. Poised for routine implementation, this method has already found success in suspected intoxication cases, promising to elevate the standards of forensic pesticide analysis.

Detection of common adulterants in bulk bovine milk using fourier transformed mid-infrared spectroscopy

Fourier transformed mid-infrared spectroscopy is a widespread method for routine analysis in milk. This method can also be used for the detection of adulterants in bovine milk which represent a current risk for dairy industries and public health. This work focuses on the detection of seven adulterants present in three known concentrations in bulk milk sample. The adulterants were: sodium bicarbonate, sodium chloride, hydroxyproline, glucose, sodium citrate, water, and urea. Partial least squares – discriminant analysis was used to develop statistical models to predict the presence of adulterants in milk samples. The obtained models could provide an easy, efficient, and rapid tool for the dairy industry to detect specific adulterants in milk.

Development of a vortex-assisted switchable-hydrophilicity solvent-based liquid phase microextraction for fast and reliable extraction of Zn (II), Fe (II), Pb (II), and Cd (II) from various baby food products

This manuscript describes the development of a novel liquid phase microextraction (LPME) method for the extraction and determination of Zn (II), Fe (II), Pb (II), and Cd (II) in various infant/baby food and supplements products. The method is based on vortex-assisted extraction combined with a switchable-hydrophilicity solvent (SHS) sample preparation. The SHS, which undergoes reversible phase changes triggered by pH change, enables selective extraction and easy phase separation. A flame atomic absorption spectroscopy was used in the final determination step. Optimization studies revealed, that the optimal pH of the sample solution (after digestion) during analytes extraction is 5.5. A l-proline is added to the sample (375 mM) to ensure the complexation of the target metal cations. After the complexation step, 750 µL of SHS - a N, N-Dimethylcyclohexylamine along with 0.9 mL of 2 M of acetic acid solution is added (hydrophilicity switch-on stage) and mixed manually to obtain a homogeneous solution. In the last stage, 0.45 mL of 10 M NaOH solution (hydrophilicity switch-off stage) is added to the sample solution and a vortex for 100 s is applied to ensure the effective extraction and separation of the complex containing the analytes. At this stage, a cloudy solution is immediately obtained. Finally, the effective phase separation is obtained at the centrifugation step (4000 rpm for 2 mins). The method limit of detection was as 0.03, 0.009, 0.6, and 0.2 ng/L for Zn (II), Fe (II), Cd (II), and Pb (II) respectively with RSD% below 2.0 %. The analysis of certified reference materials and real samples proved the full applicability of the method for routine analysis, contributing to the field of heavy metal analysis and ensuring the safety of baby products. According to the AGREE methodology, this method can be named as green analytical chemistry method with a score of 0.77.

Developing a rapid analytical method for simultaneous determination of apigenin and gallic acid: validation and application in a nanoliposomal formulation

Objective Apigenin and gallic acid are natural compounds that are useful as antioxidant, anti-inflammatory and anticancer agents, especially when used together in combination. Therefore, the development and validation of a simultaneous method of analysis for both compounds in pure form and when encapsulated in an advanced delivery system such as liposomes would be useful. Methods Analysis was performed using C18 column under isocratic conditions. The mobile phase was acetonitrile: water containing 0.2% orthophosphoric acid at a ratio of 67:33, flow rate 1 ml/min, and detection wavelength 334 nm for apigenin and 271 nm for gallic acid. Results The assay method was linear at the concentration range (5–600 µg/mL) with R2 of 1 for both drugs. The method was also shown to be precise and robust with RSD less than 2% with LOD (0.12, 0.1 µg/mL) and LOQ (4.14, 3.58 µg/mL) for apigenin and gallic acid respectively. The method was also applicable for the determination of the entrapment efficiency of both drugs when co-loaded in a nanoliposomal formulation. Conclusion The described HPLC method was shown to be suitable, sensitive, and reproducible for the simultaneous identification and quantification of apigenin and gallic acid. The analytical results were accurate and precise, with good recovery, low limit of detection, and the chromatographic assay was accomplished in less than 3 min, suggesting the suitability of the method for routine analysis of both drugs in pharmaceutical formulations.

Development and Validation of RP-HPLC Method for Routine Analysis of Osimertinib

Osimertinib is a newly approved treatment line for the non-small cell lung carcinoma actively caused by mutation in EGFR and T790M. The present study was targeted to originate a validated method for the qualification as well as quantification of osimertinib through RP-HPLC in bulk and its pharmaceutical formulation. The mobile phase, 65% triethylamine buffer (pH 2.5) and 35% acetonitrile (v/v) was run through a prontosil column (C18, 4.6×150 mm i.d., 3.5 μm particle size) at a flow rate of 0.7 ml/min. A PDA plus detector was used to scan the absorbance over 210 to 360 nm. Validation study performed following the ICH guidelines Q2 (R1) was found the developed method to be specific, precise, accurate, linear over the range of 64–96 μg/ml with R2 &gt; 0.999, robust and rugged. The % recovery of osimertinib at different levels ranged between 99.32% and 100.37% from tablet formulation (Osicent). The method holds promise for analysis of osimertinib in bulk, pharmaceutical formulations and for further research. Bangladesh Pharmaceutical Journal 27(1): 85-91, 2024 (January)

A rapid HPTLC fingerprinting technique for identifying the various geo-floral origins of honeys

Honey has several nutritional and therapeutic uses due to the presence of different bioactive compounds.These substances are derived from floral nectar. Therefore, it becomes essential to identify the distinct chemical profiles of honey samples. The aim of this research was to provide an accurate, straightforward, and sensitive HPTLC approach for different types of honey verification. Eight mono floral honeys (mustard, eucalyptus, litchi, orange, tea, Indian plum, black plum and pineapple) were collected from different origin of West Bengal (eastern India) and examined. Standard procedures were followed to check the quality of each honey.The flora was identified by microscopically examining the pollen found in honeys. High-performance thin layer chromatography (HPTLC) was used to analyze lipophilic fractions of each honey. Chromatographic results identified distinct patterns of bands with specific Rf values for each type of mono floral honey. HPTLC is a simple and effective method for routine analysis and verification. It can serve as authentication for different types of honey.

Expert System for Fourier Transform Infrared Spectra Recognition Based on a Convolutional Neural Network With Multiclass Classification.

Fourier transform infrared spectroscopy (FT-IR) is a widely used spectroscopic method for routine analysis of substances and compounds. Spectral interpretation of spectra is a labor-intensive process that provides important information about functional groups or bonds present in compounds and complex substances. In this paper, based on deep learning methods of convolutional neural networks, models were developed to determine the presence of 17 classes of functional groups or 72 classes of coupling oscillations in the FT-IR spectra. Using web scanning, the spectra of 14 361 FT-IR spectra of organic molecules were obtained. Several different variants of model architectures with different sizes of feature maps have been tested. Based on the Shapley additive explanations (SHAP) and gradient-weighted class activation mapping (GradCAM) methods, visualization tools have been developed for visualizing and highlighting the areas of absorption bands manifestation for corresponding functional groups or bonds in the spectrum. To determine 17 and 72 classes, the F1-weighted metric, which is the harmonic mean of the class' precision and class' recall weighted by class' fraction, reached 93 and 88%, respectively, when using data on the position of absorption maxima in the spectrum as an additional source layer. The resulting model can be used to facilitate the routine analysis of spectra for all areas such as organic chemistry, materials science, and biology, as well as to facilitate the preparation of the obtained experimental data for publication.