Mochammad Yuwono

Validation of Chromatographic Methods of Analysis

Publisher Summary Analytical method validation is performed by regulated laboratory, and deals with the testing of significant method characteristics to ensure that under routine use, the analytical method is accurate, precise, specific, reproducible, and rugged over the whole specified range, for which an analyte (s) is determined. The validation of chromatographic methods should be performed before the first routine use of the procedure, and a validation of methods of analysis is crucial in all phases of drug development. The necessity for validation in analytical laboratories is derived from regulations as the current Good Manufacturing Practices (cGMP), Good Laboratory Practices (GLP), and the Good Clinical Practices (GCP). Other regulatory requirements are found in quality and accreditation standards as the International Organization for Standardization (ISO) 9000 series, ISO 17025, the European Norm (EN45001) , United States Pharmacopoeia (USP) , Food and Drug Administration (FDA ) and Environmental Protection Agency (EPA). Analytical procedures are classified as being compendial or non‐compendial in character. Compendial methods are considered to be valid, but their suitability should be verified under actual conditions of use. For non‐compendial procedures, the performance parameters determine specificity/selectivity, linearity, accuracy, precision (repeatability and intermediate precision), detection limit (DL) , quantitation limit (QL) , range, ruggedness, and robustness. In chromatography techniques, selectivity can be proved by the existence of good separation between the analyte and the other components. The accuracy of an analytical method is given by the extent, by which the value obtained deviates from the true value.

Densitometric Determination of Desloratadine in Tablets, and Validation of the Method

A simple and rapid densitometric method has been developed for determination of desloratadine in tablets. After extraction of the samples with 96% ethanol the solutions were spotted on precoated silica gel TLC plates and these were eluted with ethyl acetate–n-butanol–25% aqueous ammonia–methanol, 21 + 5.0 + 4.0 + 5.0 (v/v), as mobile phase. Quantitative evaluation was performed by measuring the absorbance reflectance of the desloratadine spots at λ = 279 nm. The TLC–densitometric method is selective, precise, and accurate and can be used for routine analysis of tablets in pharmaceutical industry quality control laboratories.

HPLC Determination of Cilostazol in Tablets, and Its Validation

Abstract A simple, rapid, and validated HPLC method has been developed for determination of cilostazol in tablets. A LiChrospher 100 RP‐18 column was used with a mobile phase consisting of methanol–acetonitrile–water (20:50:30). Quantitative evaluation was performed at 260 nm. The HPLC method is selective, precise, and accurate, and it can be used for routine analysis of the preparations in pharmaceutical industry quality control laboratories.

Densitometric Determination of Tranexamic Acid in Tablets: Validation of the Method

Abstract A simple and rapid densitometric method has been developed for determination of tranexamic acid in tablets and its dissolution media. After extracting the samples with a mixture of a 96% ethanol and water (1 : 1, v/v), the solutions were spotted on precoated silica gel TLC plates, which were eluted with a mixture of n‐butanol–glacial acetic acid–water (8.0 : 2.0 : 2.0, v/v). Quantitative evaluation was performed by measuring the absorbance reflectance of the tranexamic acid spots at λ=488 nm by using ninhydrin reagent. The TLC‐densitometric method is selective, precise, and accurate, and can be used for routine analysis of tablets in the pharmaceutical industry quality control laboratories.

HPLC Determination of Piracetam in Tablets; Validation of the Method

Abstract A simple, rapid, and validated HPLC method has been developed for determination of Piracetam in film coated tablets. A Lichrospher® (100 RP‐18 column was used with a mobile phase consisting of methanol–water (5:95). Quantitative evaluation was performed at 215 nm. The HPLC method is selective, precise, and accurate and can be used for routine analysis of the preparations in pharmaceutical industry quality control laboratories.

In vitro cytotoxicity assay of Sauropus androgynus on human mesenchymal stem cells

Sauropus androgynus is a well-known Indonesian medicinal herb that is used extensively to increase human breast-milk production. However, many studies have also revealed side effects associated with bronchiolitis obliterans in Taiwan and Japan. The present study evaluated the in vitro toxic effects of S. androgynus on human mesenchymal stem cell culture derived from bone marrow (hMSCs-BM). This is the first report of a cytotoxicity assay of S. androgynus extracts from Indonesia. After 72 hours of incubating cell cultures with varying concentrations of extracts (250–2500 mg L−1), cytotoxicity was assayed by the reduction of 3-(4,5-dimethyl- thiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and reported in terms of cell viability. The apoptotic effects of the extract were determined by a terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) colorimetric assay. The S. androgynus methanol extract from East Java, Indonesia, was less cytotoxic to hMSCs-BM with an IC50 of 2450 mg L−1, but it could inhibit cell viability via the apoptosis pathway. A sample extract of plants collected near Purwosari had the lowest hMSCs-BM viability percentage (37%), while the extract from plants collected near Surabaya Pusat had a cell viability of 75%. Further studies are required to investigate the metabolites in S. androgynus that are highly correlated with its toxic effects.

Oxytetracycline: Analytical Profile

Publisher Summary This chapter deals with oxytetracycline that occurs as yellow crystals or crystalline powder, having a bitter taste and is also odorless. Oxytetracycline is produced by the growth of certain strain of Streptomyces rimosus. Detailed of compendial methods of analysis, electrochemical method, spectroscopic methods of analysis, and chemiluminescence methods are explained in the chapter. The chemiluminescence can be achieved by direct reaction or by energy‐ transfer mechanism. Capillary electrophoresis (CE) has recently become a very valuable tool for pharmaceutical analysis due to its high‐resolution speed and the very small sample volume needed. Microbiological methods are simple, versatile, and relatively cheap. However, they are time consuming and poor in terms of sensitivity and specificity. The immunoassay approaches, such as radioimmuno assays (RIAs) and enzyme‐linked immunosorbent assays (ELISAs) are the methods that offer more sensitive and selective results than microbiological methods. Different types of chromatographic methods are also described. Oxytetracycline is a broad‐spectrum antibiotic, which is been used worldwide in veterinary medicine and in aquaculture for the prevention and treatment of disease and as feed additives to promote growth.

Acyclovir: Comprehensive Profile

Publisher Summary The chapter presents a comprehensive profile of acyclovir. In compendial methods of analysis, the identification of acyclovir is verified on the basis of characteristic infrared absorption. Identification is effected using a liquid chromatography procedure. Other compendia also use the infrared absorption method for identification purposes. The chapter outlines two categories of assay methods for compendial methods of analysis, such as acyclovir bulk drug substance and acyclovir in pharmaceutical preparations. An official method for the assay of acyclovir is based on the use of potentiometric titration. The chapter describes various spectrophotometric methods for the assay of acyclovir in its pharmaceutical preparations, such as cream formulations, eye ointment formulations, intravenous infusion formulations, and tablets. A fluorimetric method for the assay of acyclovir in oral suspension preparations is discussed. The chapter describes the application of selected reaction monitoring/mass spectrometry for the determination of acyclovir and ganciclovir in plasma and tissue. The chapter also presents the chromatographic methods of analysis, such as thin-layer chromatography, high-performance liquid chromatography, and capillary electrophoresis.

Densitometric Determination of Allylestrenol in Tablets, and Validation of the Method

Abstract A simple and rapid densitometric method has been developed for determination of allylestrenol in tablets. After extracting the samples with 96% ethanol, the solutions were spotted on pre‐coated silica gel TLC plates, which were eluted with a mixture of n‐hexane–ethyl acetate–dichloromethane (9.0:2.0:0.2, v/v). Quantitative evaluation was performed by measuring the absorbance reflectance of the allylestrenol spots at λ = 609 nm, after reaction with anisaldehyde–sulphuric acid reagent (5 min, 100°C). The TLC‐densitometry method is selective, precise, and accurate, and can be used for routine analysis of tablets in pharmaceutical industry quality control laboratories.