Liquid chromatographic determination of sitagliptin either alone or in ternary mixture with metformin and sitagliptin degradation product

Simultaneous determination of sitagliptin and metformin in ternary mixture with sitagliptin acid degradation product

“…Structure elucidation of the obtained secondary amine was confirmed using infra-red, mass and 1 H NMR spectroscopic techniques and proved to be: 3-amino-4-(2,4,5-trifluorophenyl) butanoic acid. It is worth noting that the other hydrolysis product which is: 3-(trifluoromethyl)-5,6,7,8-tetra hydro-[1,2,4]triazolo[4,3-a]pyrazine could not be separated from the reaction medium with the acid but it was studied in a previous work by the same authors of this work [7]. The IR spectrum of SDP showed the shift of the characteristic peak of the carbonyl group of the amide bond at 1639 to 1697 cm -1 which is the characteristic peak of the carbonyl group of the carboxylic acid in addition to the appearance of the characteristic broad peak of the OH of the carboxylic group.…”

“…In a previous work by the same authors of the present work [7], the determination of STG was carried out alone and was also simultaneously determined with MET in the presence of STG alkaline degradation product (SDP). However, the acid degradation of STG could not be separated.…”

“…A few methods have been described for the determination of STG in pharmaceutical preparations including spectrophotometry [1,6], HPLC [2,3,7] and fluorometry [8]. Besides, some methods have been reported for determination of MET in pharmaceutical preparations including LC/MS/MS [4] and HPLC [9][10][11].…”

Voltammetric Assay of Metformin Hydrochloride Using Pyrogallol Modified Carbon Paste Electrode

“…[1][2][3] Published methods for the determination of MET are based on different techniques like capillary electrophoresis, 4,5 NMR spectrometry, 6 potentiometry, [7][8][9] spectrofluorimetry and spectrophotometry, [9][10][11][12][13][14][15][16][17][18][19][20] conductometry, 21,22 voltammetry, [23][24][25][26][27][28][29] IR spectrometry 30 and chromatography. [31][32][33][34][35][36][37][38][39] Although many of the reported methods are accurate and sensitive, they require the use of sophisticated equipment and expensive reagents. Some are cumbersome, requiring prolonged sample pretreatment, strict control of p-H and long reaction times.…”

Development and validation of a reversed phase liquid chromatographic method for the determination of three Gliptins and Metformin in the presence of Metformin impurity (1-cyanoguanidine)

“…Few methods have been described for the determination of STG in pharmaceutical preparations or biological fluids including spectrophotometry [2] and high performance liquid chromatography (HPLC) [1,3]. A liquid chromatographic (LC) method was reported for the determination of STG in ternary mixture with MET and sitagliptin degradation product [4]. For VDG, literature survey reveals that only one spectroscopic method and one LC method were reported for its determination [5,6].…”