Ultrasound-Assisted One-Pot Cloud Point Extraction for Iron Determination Using Natural Chelating Ligands from Dipterocarpus intricatus Dyer Fruit

An ultrasound-assisted, one-pot cloud point extraction was developed for the determination of iron in vegetable samples by UV-Visible spectrophotometry. This method was based on the complexation of iron with an environmentally-friendly natural chelating agent extracted from Dipterocarpus intricatus Dyer fruit at pH 5.5 in the presence of Triton X-114. Reagent extraction, complexation, and preconcentration were performed simultaneously using ultrasound-assisted extraction at 45 °C. The surfactant-rich phase was diluted with ethanol and loaded through a syringe barrel packed with cotton that acted as a filter to trap the reagent powder. Analyte-entrapped on cotton was eluted using 0.1 mol·L⁻¹ nitric acid solution. Filtrate and eluate solutions were measured absorbance of the dark-blue product at 575 nm. Influential parameters for the procedure were investigated. Under the optimum experimental conditions, the calibration curve was linear, ranging from 0.1 to 1.0 mg·L⁻¹ with r² = 0.997. Limits of detection and quantification were 0.03 and 0.09 mg·L⁻¹, respectively while precision values of intra-day and inter-day were less than 5%. Recovery at 0.5 mg·L⁻¹ ranged from 89.0 to 99.8%, while iron content in vegetable samples ranged from 2.45 to 13.36 mg/100 g. This method was cost-effective, reliable, eco-friendly, and convenient as a green analytical approach to determining iron content.

A simple and green LC method for the determination of ibuprofen in milk-containing simulated gastrointestinal media for monitoring the dissolution studies of three dimensional-printed formulations

A fast and green ultra high-performance LC method was developed for the determination of ibuprofen in milk-containing simulated gastrointestinal media to monitor the dissolution of three-dimensional printed formulations. To remove interfering compounds, protein precipitation using methanol as a precipitation reagent was performed. The separation of the target analyte was performed on an C18 column using a mobile phase consisting of 0.05% v/v aqueous phosphoric acid solution: methanol, 25:75% v/v. Method validation was conducted using the total error concept. The β-expectation tolerance intervals did not exceed the acceptance criteria of ± 15%, meaning that 95% of future results will be included in the defined bias limits. The relative bias ranged between ─ 1.1 to + 3.2% for all analytes, while the relative standard deviation values for repeatability and intermediate precision were less than 2.8% and 3.9%, respectively. The achieved limit of detection was 0.01 μg mL^-1 and the lower limit of quantitation was established as 2 μg mL^-1 . The proposed method was simple, and it required reduced organic solvent consumption following the requirements of Green Analytical Chemistry. The method was successfully employed for the determination of ibuprofen in real biorelevant media obtained from dissolution studies. This article is protected by copyright. All rights reserved.

A Mini Review on Characteristics and Analytical Methods of Otilonium Bromide

Irritable bowel syndrome (IBS) is a world-wide disease prevalently in Western nations. It influences about 15% of the western populace, with a negative effect on the quality of life and furthermore on medical services costs. Anticholinergic antispasmodics are first line of treatment for discomfort or abdominal pain, particularly if unrelieved after alleviation of stoppage or antidiarrheal treatment. Otilonium bromide (OTB) is quaternary ammonium compound with action on distal GI tract as antispasmodic. It is utilized in the treatment of patients influenced by Irritable inside disorder (IBS) because of its particular pharmacokinetic and pharmacodynamic properties. OTB is poorly absorbed systematically was viable in contrast with different medications used for same purpose, for example, pinaverium bromide and mebeverine, with a good tolerability profile. The effects are long lasting, even after stopping the dosage regime for reduction of abdominal pain. In this review, an overview of mechanism of action, pharmacologic action, synthesis and particularly various analytical and bioanalytical methods are discussed. The analytical methods discussed are spectrophotometry including Near Infrared Spectroscopy (NIRS), chromatography and capillary electrophoresis methods are described with the range, limit of detection and quantification. The paper also provides details of scope of further extension of analytical methods. It was found that most of the analytical methods involves usage of toxic solvents e.g., methanol, acetonitrile, chloroform etc. posing risk to the analyst as well as environment.

A sustainable UPLC-UV method for quantification of donepezil hydrochloride in biorelevant media applied to dissolution profile comparison

Donepezil hydrochloride is one of the most prescribed anti-Alzheimer's drugs, despite being available for more than two decades, chromatographic methods for the quantification of the drug in biorelevant media that mimics pH physiological conditions in vivo (pH 1.2, 4.5, and 6.8) are not available in the literature. These media are used in the dissolution test, an important tool, for registration and quality control of medicines. Considering the need for methods with this purpose, this work aimed to develop and validate a sustainable UPLC-UV method for quantification of donepezil hydrochloride in tablets, specifically on assay and dissolution profile, with reduced environmental impacts. The proposed method has a run time of 2 min and requires for each run, only 0.8 mL of solvents, providing excellent green analysis. The method proved to be selective, linear, precise, accurate, robust in the range of 2-14 µg/mL. Three products (reference, similar, and generic) were analyzed and showed very rapid dissolution. The average content varied from 100.2 ± 0.6% to 109.5 ± 2.1%. Using dissolution efficiency (DE), the drug release profiles were compared in different biorelevant media.