Substantiation of an approach to determination of ketoprofen macrogol 400 esters

The aim. work is concerned with the substantiation of approach to identification and quantitative determination ketoprofen macrogol 400 esters. Materials methods. Ketoprofen, 400, ester (KM400E), as well model cream-gels were studied by following methods: absorption spectrophotometry ultraviolet (UV) visible, high-performance liquid chromatography (HPLC), gas (GC), GC / mass spectrometry, nuclear magnetic resonance (NMR) spectrometry thermogravimetry. Results. It was found that average molecular (Mr) test 383.50 it contains oligomers masses from 150.17 546.65. KM400E, which a mixture esters oligomers, synthesized. formed characterized 1H NMR spectra. shown ratio calculated for monoesters, corresponds specific absorbances solutions this fact indicated formation monoesters. Taking into account risk variability fractional composition in different batches, advisable quantify KM400E using reference standard (RS) not RS. Using HPLC diode array detection peak should be identified UV spectrum λmax≈255 nm, characteristic ketoprofen, relative retention time (RRt) peak; quantified content impurity. During storage impurity significantly lower than propylene glycol (mixture isomers). Conclusions. substantiated. analytical procedure RS developed. Correctness proved results validation studies.