Transfer of thin layer chromatography (TLC) methods for semiquantitative detection of counterfeit and substandard pharmaceutical products published in the Global Pharma Health Fund (GPHF) Minilab and U.S. Food and Drug Administration (FDA) Compendium of Unofficial Methods for Screening of Pharmaceuticals to high performance TLC (HPTLC)-densitometry quantitative methods using a model process has been reported earlier in a series of papers. In this paper, HPTLC-densitometry methods developed and validated using the model process are described for analyzing the products containing aminophylline, bisoprolol fumarate, griseofulvin, hydrochlorothiazide, and pyrimethamine for which screening methods have been published in the Minilab Manual. HPTLC-densitometry methods have also been described for analyzing the products containing bupropion HCl, carbamazepine, clomiphene citrate, mirabegron, and oxybutynin Cl, for which screening methods are not included in the Minilab Manual or FDA Compendium. These new methods use only relatively inexpensive and nontoxic solvents for preparation of sample and standard solutions and mobile phases; Merck KGaA Premium Purity HPTLC silica gel 60 F254 plates; semiautomated standard and sample solution application with a CAMAG Linomat 4; mobile phase development in a CAMAG twin trough chamber; automated densitometry using a CAMAG Scanner 3 for detection, assessment of peak purity and identity, quantitative assay; and validation by standard addition. Qualitative TLC screening methods based on the quantitative HPTLC-densitometry methods for the drug products not covered in the Minilab Manual or FDA Compendium were subsequently developed as supplements to the FDA Compendium and posted online with open access.
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