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47. Chiral resolution methods for racemic pharmaceuticals based on cocrystal formation.

Author

Kaviani, Raha, Jouyban, Abolghasem, and Shayanfar, Ali

Subjects
RESOLUTION (Chemistry), CHIRAL drugs, RACEMIC mixtures, ASYMMETRIC synthesis, DRUG marketing, DRUGS, ENANTIOMERIC purity
Abstract

Currently, more than half of available drugs on the market are chiral, and approximately 90% of these drugs are marketed as racemates. When these racemic medications are exposed to the chiral environment of the human body, differences in their activity appear. The enantiomers of a chiral drug may potentially have distinct pharmacokinetic, metabolic, and toxicological features. As a result, regulatory requirements promote the production of enantiopure drugs to reduce the complexity of pharmacodynamics and the administration dose or to eliminate unwanted side effects, while also providing some economic savings by enabling a totally effective pharmaceutical formulation. There are a variety of procedures employed in the pharmaceutical industry for chiral separation of racemic drugs, such as developing de novo enantiomerically pure pharmaceuticals by asymmetric synthesis or chiral resolution of currently available racemic compounds via different approaches like chiral chromatography methods, diastereoisomeric salt formation, and cocrystallization-based methods. This review will focus on cocrystallization techniques such as the generation of host–guest inclusion compounds, diastereomeric cocrystal pairs, enantiospecific cocrystals, conglomerates, ionic cocrystals, and preferential enrichment of cocrystals. Overall, this review outlined the crucial importance of pharmaceutical cocrystals in chiral resolution techniques of racemic compounds. [ABSTRACT FROM AUTHOR]

Published
2023
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50. Salting-Out Assisted Liquid-Liquid Extraction for Quantification of Ammonia Compounds in Food Samples.

Author

Ziban, Behnaz, Nemati, Mahboob, and Shayanfar, Ali

Subjects
AMMONIA compounds, LIQUID-liquid extraction, BREAD, SOLUTION (Chemistry), POTASSIUM chloride, RESPONSE surfaces (Statistics), EXTRACTION techniques
Abstract

The extraction of ammonia compounds from food samples is a challenging topic due to the hydrophilic property of ammonia. A simple and rapid extraction method was developed for the determination of ammonia in a type of local bread (Ahari bread) and milk samples using a salting-out assisted liquid-liquid extraction and spectrophotometry. Acetonitrile was used to clean up, and potassium chloride salt solution was added to separate the acetonitrile and aqueous phase by creating two phases. The ammonia concentration in the aqueous phase was determined based on a colorimetric method. Various parameters affecting absorption intensity were optimized using the response surface methodology. Then, the optimized parameters were applied to establish a valid analytical method. The developed method was used to quantify ammonia compounds in food samples, i.e. Ahari bread and milk, by the standard addition method. The linearity of the method was from 2.5 to 40 µg ml with a coefficient of determination (R2) of 0.994, and numerical values of a limit of detection, and limit of quantification was found to be 0.39 and 1.29 µg ml-1, respectively. The accuracy (%error) and precision (%relative standard deviation) were in the acceptable range. The established extraction technique and standard addition method could detect ammonia in real food samples. These data showed that the established analysis approach is a simple and sensitive technique for extraction and determination of ammonia concentration in foodstuff. [ABSTRACT FROM AUTHOR]

Published
2023

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