Determination of chemical stability of sitagliptin by LC-UV, LC-MS and FT-IR methods.

Sitagliptin was stored at high temperature/high humidity, dry hot air, UV/VIS light and different pH. Then, a selective LC-UV method was developed for determination of sitagliptin in the presence of degradation products and for estimation of degradation kinetics. Because parent drugs can react with excipients in final pharmaceutical formulations, stability of sitagliptin was also examined in the presence of excipients of different reactivity, using FT-IR and LC-UV methods.

Correction: Chemical stability and interactions in a new antihypertensive mixture containing indapamide and dihydralazine using FT-IR, HPLC and LC-MS methods.

[This corrects the article DOI: 10.1039/C8RA06707D.].

Chemical stability and interactions in a new antihypertensive mixture containing indapamide and dihydralazine using FT-IR, HPLC and LC-MS methods.

Indapamide and dihydralazine can be combined in fixed-dose formulations because of their complementary actions against hypertension. On the other hand, combined formulations present the problem of chemical interactions between the active ingredients, accelerated degradation of constituents or generation of quite new degradation products. Therefore, the main goal of the present study was to examine the chemical stability of indapamide and dihydralazine, as individuals and as a mixture, to detect potent interactions between both constituents, using FT-IR, HPLC and LC-MS methods.

New hydrazide-hydrazones of isonicotinic acid: synthesis, lipophilicity and in vitro antimicrobial screening.

This study describes the synthesis, lipophilicity and in vitro antimicrobial assays of 15 new hydrazide-hydrazones of isonicotinic acid. New derivatives were obtained on the basis of the condensation reaction of isonicotinic acid hydrazide with different aromatic aldehydes. The chemical structure of synthesized compounds was confirmed by spectral methods.

Stability-indicating validated HPLC method for simultaneous determination of oral antidiabetic drugs from thiazolidinedione and sulfonylurea groups in combined dosage forms.

For type 2 diabetes treatment, combinations of drugs from the thiazolidinedione and sulfonylurea groups are now available in the same tablet or capsule. Therefore, a stability-indicating and validated HPLC method was developed for simultaneous determination of pioglitazone, rosiglitazone, and glipizide in combined dosage forms. The examined drugs were subjected to different conditions such as acid and base, temperature, and UV light, and degradation of pioglitazone and glipizide was observed under thermal and acidic stress.

Revisiting thin-layer chromatography as a lipophilicity determination tool--a comparative study on several techniques with a model solute set.

The lipophilicity of a compound is a fundamental property related to pharmaceutical and biomedical activity. As many approaches are mixed together in every-day published studies, the subject needs some standardization. The paper presents a comparative study on several approaches of TLC lipophilicity determination: a single TLC run, extrapolation of a retention, principal component analysis of a retention matrix, PARAFAC on a three-way array and a PLS regression.

Development and validation of a new high-performance liquid chromatography method for the determination of gliclazide and repaglinide in pharmaceutical formulations.

A new high-performance liquid chromatography method was developed and validated for the quantitation of gliclazide and repaglinide in pharmaceutical formulations. Determination was performed using a LiChroCART RP-18 column, a mobile phase containing acetonitrile-phosphate buffer (pH 2.1; 60 + 40, v/v), and ultraviolet (UV) detection at 225 nm.