A Rapid and Cost‐Effective Absorption Factor Method for the Multicomponent Quantification of Paracetamol and Orphenadrine

Development and validation of colorimetric-assisted chemometrics methods based on the localized gold nanoparticles surface plasmon resonance for fast simultaneous estimation of anti-hepatitis C virus drugs in their combined dosage form: A comparative study with HPLC method

Background: Chromolaena odorata (Siam weed) is a perennial shrub used in the treatment of many ailments and disease conditions, also known as Siam weed. A potential weed of tropical and sub-tropical regions inhabits waterways. The medicinal values of Chromolaena odorata lie in their phytochemical's component. The present study aims to develop and validate an UV spectrophotometric method according to ICH guidelines for the estimation of C. odorata. Materials and Method: The study is focused on generating a specific, linear, accurate and precise UV spectrophotometric method for estimation of aqueous C. odorata. The method's parameters were assessed within a concentration range of 0.2 µg/ml - 1 µg/ml, with recovery rates specifying accuracy and low % relative standard deviation (RSD) values confirming precision. Limits of detection (LOD) and quantification (LOQ) for C. odorata were determined. Results and Discussion: Validation is conducted to ensure that the analytical methods are accurate, specific, reproducible, and resistant to the analyte range to be analyzed. The method was validated for many parameters. Solvent development step involves the use of water in which Siam showed spectrum with maximum absorbance at 211nm. A coefficient of correlation of 0.9975 was discovered in accordance with Beer's law. After determining the technique's sensitivity, the limit of detection and limit of quantification were determined to be 1.07 µg/ml and 3.25 µg/ml, respectively. Conclusion: In conclusion, the development and validation of a UV-visible spectrophotometric method for the estimation of aqueous Chromolaena odorata extracts demonstrate a promising approach for routine quality control analysis. The method offers a simple, cost-effective, and efficient means of analysis when adequately optimized. The validation according to ICH Q2 (R1) guidelines confirms that the method meets the necessary acceptance criteria, making it suitable for the routine analysis of Chromolaena odorata.

A simple, accurate, rapid and sensitive UV spectrophotometric method has been developed for the estimation of Tenofovir disoproxil fumarate (TDF) in bulk as well as in Pharmaceutical dosage form. TDF is used as antiretro-viral agent. The present research work involves the estimation of TDF using methanol as solvent. An absorption maximum (λ max) was found to be 259.5 nm. It obeys the beer's law in the concentration range of 550 μg/ml with a correlation coefficient value of 0.9998. Validation of the method has been carried out statistically as per ICH guidelines and the results were found to be satisfactory. The result of mean % recovery was found to be 99.42 + 0.36% for TDF which shows that the method was not affected by the presence of common excipients in tablet dosage form. The % RSD for both inter-day and intra-day precision was found to be less than 2.0%. The limit of detection and limit of quantification were found to be 0.47 μg/ml and 1.63 μg/ml respectively. The method was validated by determining its sensitivity, linearity, accuracy and precision which proves suitability of the developed method for the routine quality control analysis for the estimation of Tenofovir disoproxil fumarate (TDF) in bulk and tablet dosage form.

An environmentally friendly and simple method was developed for the simultaneous separation and determination of Rhodamine B (RhB) and Rhodamine 6 G (Rh6G) in red pencil samples by vortex assisted microextraction using NADES (Natural Deep Eutectic Solvent). A two-phase system was established using lactic acid-based DES (Deep Eutectic Solvent) and tetrahydrofuran (THF) for the extraction of RhB and Rh6G. In method optimization, sample amount, pH, DES type, DES volume, solvent type and solvent volume parameters were investigated. Limit of detection (LOD) and limit of quantification (LOQ) values were 4.13, 5.03 and 12.5, 15.3 µg/mL for RhB and Rh6G, respectively. The correlation coefficients obtained at concentrations ranging from 1–12 µg/mL are 0.9973 and 0.9985. Red pencil samples were spiked at two different concentrations (3–5 µg/mL). The recovery values obtained were in the range of 84.7%-107.4%. The relative standard deviation (RSD) values of the developed method are in the range of 2.77%-5.45%, indicating that the method is reproducible. The results showed that the developed microextraction method can be successfully applied for the separation and determination of RhB and Rh6G from red pencil samples.

Lobeglitazone sulfate is a novel thiazolidinedione drug used for the therapy of type 2 diabetes. Recent pre-clinical studies show that the drug is also effective in attenuating mucus hypersecretion and airway inflammation caused due to ovalbumininduced asthma. This study aimed to develop an accurate, simple, and cost-effective analytical method for the quantification of lobeglitazone sulfate in bulk and pharmaceutical dosage forms by UV spectrophotometric technique. The drug was identified by FTIR (ATR) instrument and the method development was performed with methanol as the solvent. In compliance with the ICH Q2(R2) guidelines, all the important validation parameters, such as linearity, accuracy, Limit of Detection (LOD), precision, specificity, Limit of Quantification (LOQ), and robustness were determined. The maximum absorption wavelength of lobeglitazone sulfate was found to be 248 nm. The linearity range was established from 2-14 μg/mL with a linearity equation of y = 0.0361x + 0.0024 and r² = 0.9987. The accuracy of the analytical method was found to be in the range of 99.37-100.41%. The precision studies were performed under three subsets of repeatability, intra-day, and inter-day, and the results recorded were within the acceptance limits, i.e., %RSD (<2%). The developed analytical method's Limit of Detection (LOD) and Limit of Quantification (LOQ) values were 0.07 μg/mL and 0.22 μg/mL, respectively. The developed analytical method has been found to be valuable in regular quality control analysis of lobeglitazone sulfate in pharmaceutical industries. The adopted approach of the developed method has been found to be facile, accurate, precise, and economical.

A highly sensitive and specific spectrofluorimetric method for the analysis of captopril (CAP) in the pure form and in the tablet dosage forms has been described. The method was based on the oxidation of captopril by cerium(IV) in the presence of sulphuric acid and subsequent monitoring the fluorescence of the induced Ce(III) ion produced at λex= 256 nm and λem= 354 nm. All variables affecting the reaction conditions such as cerium(IV) concentration, type and concentration of acid medium, reaction time, diluting solvents, temperature and heating time were carefully studied and optimized. Under the experimental conditions used, an excellent linear relationship was obtained between fluorescence intensity and the concentration of CAP. A linear range of determination was verified for captopril concentrations between 0.1–1.3 μg mL−1and the correlation coefficient of determination was 0.9997. Quantitation and detection limits were calculated. The precision of the method was satisfactory; the values of relative standard deviations did not exceed 1.14%. No interference could be observed from the excipients and additives are commonly presented in dosage forms. The proposed method was applied successfully for the assay of the studied drug in pure form and in pharmaceutical dosage forms. Recovery experiments revealed recovery of 99.82–100.21%. The results of the analysis show a good agreement with those obtained by official method stated in the United State Pharmacopoeia.

In this study, a green synthesis strategy was developed to fabricate highly stable gold nanoparticles (AuNPs) using the extract from discarded longan peel, designated GN-LP. The synthesized GN-LP has an average particle size of 11.94 ± 4.83 nm, a zeta potential of – 28.4 mV, a typical face-centered cubic (fcc) crystal structure and enriched with oxygen-containing functional groups, acted as the primary reducing agents. The optimal conditions for streptomycin (STR) detection were as follows: 0.6 M potassium chloride (KCl), an aptamer concentration of 75 nM, and a reaction time of 45 min. Under these optimized conditions, a smartphone-based colorimetric aptasensor was established, exhibiting a linear absorbance–concentration relationship within the range of 400.0 ng·mL-1–2400.0 ng·mL-1. The limit of detection (LOD) and limit of quantification (LOQ) were calculated as 126.74 and 425.48 ng·mL-1, respectively. The method was successfully applied to detect STR in environmental waters, yielding recovery rates between 96.8% and 109.4%, with values of relative standard deviation (RSD) below 9.6%. The results offer operational simplicity, high sensitivity, minimal solvent consumption, and environmental sustainability, making it well-suited for on-site STR monitoring in real water.

A fast and simple multi-residue method for the analysis of 15 organophosphorus (OP), 17 organochlorine (OC), 8 pyrethroids (PYR), 12 N-methyl-carbamate (NMC) pesticide residues and bromopropylate in honey is presented. Ready–to–use EXtrelut®NT 20 column, eluted with dichloromethane, was used to extract the pesticide residues from the aqueous-acetone honey sample, obtaining a clean extract directly analyzable. Determination was carried out by gas chromatography (GC) coupled with flame photometric detector (FPD) for OP compounds and by GC coupled with mass spectrometry detector (MSD) for OC and PYR pesticides and bromopropylate. The NMC pesticides were analysed by liquid chromatography-double derivatization coupled with spectrofluorimetric detector (LC/DD/Fl). This method allows the determination of the 53 pesticide residues at low concentrations (0.0005–0.074 mg/kg) and can be used to assess the compliance with the Maximum Residues Levels (MRLs) set by the European Union. The performance of the method was evaluated and specificity, linearity, recovery, repeatability, reproducibility, limit of quantification (LOQ) and limit of detection (LOD) were determined. A good linearity (r2⩾ 0.99) was found in the range 0.0005–0.074 mg/kg for the majority of the compounds studied. Most of the pesticides had recoveries in the range 70–103 % and values of relative standard deviation (RSD) < 20 for repeatability and reproducibility, showing good accuracy and precision of the method. Aldicarb partially degraded in aldicarb sulphoxide during the analytical procedure, giving anomalous values. The LOQ for all pesticides investigated was from 0.0005 to 0.025 mg/kg while the LOD ranged from 0.0002 to 0.008 mg/kg.

Evogliptin is an anti-diabetic drug, which comes under the class of gliptin derivatives for the inhibition of selective dipeptidyl peptidase-4 inhibitor. The developed ultraviolet spectrophotometric method was simple, sensitive, accurate, precise and economic for the development and validation of evogliptin in bulk and tablet dosage form. In this present study, the analytical method validation and development of evogliptin was done using the different parameters of method validation as per International Council for Harmonisation Q2(R1) guidelines. Water using as a solvent and it shows the maximum wavelength at 266 nm and then performed all the parameters of analytical method validation like accuracy, precision, linearity, range, robustness, ruggedness, limit of detection and limit of quantitation. Evogliptin showed linearity over the range of 2-48 µg/ml. The correlation coefficient value obtained was 0.996 with the regression equation y=0.0032x+0.0005. The accuracy studies was done in spiking method and the recoveries ranging from 97.07 %-106.13 %. The percentage relative standard deviation for intra-day precision was 0.44 and inter-day precision was 0.59. The limit of detection was 1.1 µg/ml and limit of quantitation was 3.33 µg/ml respectively. The method has shown good and consistent recoveries and is validated as per International Council for Harmonisation guidelines and can be used for routine quality control analysis of evogliptin in dosage form.

A new and completely automated method for the determination of ten relevant polycyclic aromatic hydrocarbons (PAHs) in olive oil is proposed using an extraction by the headspace (HS) technique. Quantification and confirmation steps are carried out by gas chromatography-mass spectrometry (GC-MS) combining simultaneously selected-ion monitoring (SIM) and tandem mass spectrometry (MS/MS). This combination offers on one hand an increased sensitivity and on the other hand, selective and reliable qualitative information. Sample pretreatment or clean-up are not necessary because the olive oil sample is put directly into an HS vial, automatically processed by HS and introduced into the GC-MS instrument for analysis. Because of its high selectivity and sensitivity, a triple-quadrupole (QqQ) detector coupled with the gas chromatograph allows us to limit handling. Each sample is completely processed in approximately 63 min (45 min for HS isolation and 18 min for GC-MS determination), a reduced time compared with previously published methods. The chemical and instrumental variables were preliminarily optimized using uncontaminated olive oil samples spiked with 25 microg kg(-1) of each target compound. The final method was validated to ensure the quality of the results. The precision was satisfactory, with relative standard deviation (RSD) values in the range 3-9%. Recovery rates ranged from 96 to 99%. Limits of detection (LOD) were calculated as 0.02-0.06 microg kg(-1) and the limits of quantification (LOQ) were obtained as 0.07-0.26 microg kg(-1). It must be mentioned that the LOD and LOQ are much lower than the maximum levels established by the European Union (EU) in oils and fats intended for direct human consumption or for use as an ingredient in foods, which are set at 2 microg kg(-1). All the figures of merit are completely in accordance with the latest EU legislation. This fact makes it possible to consider the proposed method as a useful tool for the control of PAHs in olive oils.

A simple yet sensitive high performance liquid chromatography method was developed and validated for the determination of paracetamol (PCM) content in different tablets dosage form. The mobile phase consisted of a mixture of methanol: water (80:20 v/v). The HPLC analysis was performed at a flow rate of 1 mL/min using a Thermo Synchronise C18 (150 × 4.6mm, 5μM) and an UV detection wavelength of 254 nm was used. The method was validated for selectivity, linearity, precision, accuracy, limit of quantification (LOQ), limit of detection (LOD), robustness and solution stability. The calibration curve was linear over a concentration range of 20 to 70 µg/mL (r2 = 0.9997) with LOD and LOQ of 0.01 and 0.03 μg/mL, respectively. The retention time for paracetamol was 1.5 min. The relative standard deviation percent (%RSD) and the relative error percent (%RE) of calibration curve were between 0.03-1.03% and 0.05-1.11%, respectively. The intra- and inter-day precision and accuracy were between 0.02-1.55% and 0.10-0.78%, respectively. In addition, the %RSD of short term stability and the method robustness were between 0.4-1.20% and 0.09-1.43%, respectively. All results followed the ICH guideline Q2 (R1) which indicates the precision and accuracy of the developed method. The method was successfully applied to assess PCM content in different marketed tablets in Iraq.

L‑Carnosine is a naturally occurring dipeptide widely used in pharmaceutical and nutraceutical formulations due to its antioxidant and anti-aging properties. The present study focuses on the development and validation of a simple, rapid, and economical analytical method for the quantitative estimation of L-Carnosine in tablet dosage form using UV–Visible Spectrophotometry. The method was developed using a suitable solvent system and the absorbance of L-Carnosine was measured at its maximum wavelength. Then the developed method is applied on the quantification of marketed formulation. The developed method was validated according to the guidelines of ICH and the parameters such as linearity, solution stability, accuracy, precision, specificity, limit of detection, limit of quantification, and robustness. The results indicated that the method is reliable and reproducible for the routine analysis of L-Carnosine in tablet formulations by UV Spectrometry. This method is suitable for this drug in pharmaceutical industries.

A simple and sensitive thermochemically induced fluorescence (TIF) method was developed to determine deltamethrin, an insecticide which has toxic effects on human beings and animals. After optimisation at different pH, temperature was increased from 25 to 50°C. TIF method is based on the thermolysis transformation of naturally non-fluorescent pesticides into a fluorescent thermoproduct. The thermolysis kinetics reaction investigated in water at optimal pH 12 and after 4 minutes heating at 40°C made it possible to obtain a low mean half-life time (t 1/2 = 1.41 ± 0.06 min), which shows that deltamethrin degrades very rapidly due to heat. The obtained calibration curve gave correlation coefficients close to unity. The limit of detection (LOD = 4.4 ng mL−1) and quantification (LOQ = 15 ng mL−1) values were very low, showing the high sensitivity of the TIF method. TIF method was applied to determination of deltamethrin residues in tap and well waters by standard addition procedure, with satisfactory recovery values between 107.6 and 111.4%. The relative standard deviation (RSD) value of the measured concentrations in spiked water samples was less than 6%, which demonstrated good reproducibility of the TIF method.

Objectives : Ongyeong-tang (OGT) is a traditional herbal formula used to cure gynaecological disorders. OGT consists of 12 herbal medicines containing various bioactive components. Therefore, the development of suitable analytical method for the marker compounds is necessary for the quality control of OGT. Methods : Determination of the 18 marker compounds in OGT preparations was quantitatively performed by high-performance liquid chromatography-photodiode array detection analysis. The marker compounds were separated on a reversed-phase C ₁₈ column and the analytical method was successfully validated, which was applied to compare OGT extracts from laboratory preparation and commercial OGT granules. Results : Limit of detection and limit of quantification values were in the ranges of <TEX>$0.001-0.016{\mu}g/mL$</TEX> and <TEX>$0.003-0.047{\mu}g/mL$</TEX>, respectively. Precision was 0.03-3.71 % within a day and 0.03-3.81 % over four consecutive days. Recovery of marker compounds ranged from 90.63-108.26 %, with relative standard deviation (RSD) values < 4.0 %. Reproducibility was < 2.5 % of the RSD value. The 18 marker compounds were stable within 16 h at <TEX>$10^{\circ}C$</TEX>, with the RSD value < 3.5 %. Quantitative analysis results showed that the quantities of the 18 marker compounds varied among OGT samples. Pearson coefficient evaluation and principal component analysis demonstrated that an OGT water extract produced by a laboratory method clearly differed from commercial OGT granules. Conclusions : The developed analytical method was simple, precise, and reliable. Therefore, it can be used for the quality assessment of OGT preparations.

Objectives : Ongyeong-tang (OGT) is a traditional herbal formula used to cu re gynaecological disorders. OGT consists of 12 herbal medicines containing various bioactive co mponents. Therefore, the development of suitable analytical method for the marker compounds is necessary for the quality control of OGT. Methods : Determination of the 18 marker compounds in OGT preparations w as quantitatively performed by high-performance liquid chromatography –photodiode array detection analysis. The marker compounds were separated on a reversed-phase C 18 column and the analytical method was successfully validated, which was applied to compare OGT extracts from laboratory preparation and commercial OGT granules.Results : Limit of detection and limit of quantification values were in the ranges of 0.001–0.016µg/mL and 0.003–0.047µg/mL, respectively. Precision was 0.03–3.71% within a day and 0.03–3.81% over four consecutive days. Recovery of marker compounds ranged from 90.63–108.26%, with relative standard deviation (RSD) values<4.0%. Reproducibility was <2.5% of the RSD value. The 18 marker compounds were stable within 16 h at 10℃, with the RSD value <3.5%. Quantitative analysis results showed that the quantities of the 18 marker compounds varied among OGT samples. Pearson coefficient evaluation and principal component analysis demonstrated that an OGT water extract produced by a laboratory method clearly differed from commercial OGT granules.Conclusions : The developed analytical method was simple, precise, and reliable. Therefore, it can be used for the quality assessment of OGT preparations.Key words : Ongyeong-tang, Quantitative analysis, Method development, Pear son coefficient, Principal component analysis