Trifluoromethanesulfonic acid as a catalyst for the formation of dansylhydrazone derivatives

Determination of progesterone and 17-hydroxyprogesterone by high performance liquid chromatography after pre-column derivatization with 4,4-difluoro-5,7-dimethyl-4-bora-3a,4a- diaza-s-indacene-3-propionohydrazide

“…Hydrochloric acid and trifluoroacetic acid have been used as catalysts in methanol or ethanol solution. [6][7][8][9] Recently, the use of triflouromethanesulfonic acid was also reported, 10,11 but it is very hazardous and not easy to use. Moreover, it was necessary to decompose the excess trifluoromethanesulfonic acid with 2 m aqueous ammonia.…”

“…3), e.g., over 1.5 h at 50 °C and over 11 h at 25 °C. Room temperature was selected in all previous work using dansylhydrazine [6][7][8][9][10][11] to avoid the decomposition of steroids and metabolites in biological samples. We therefore selected 15 h at room temperature (about 22 °C) Comparison of derivatizing reagents.…”

“…As simultaneous determinations were needed for each metabolite, chromatographic methods were the main approach used. Gas chromatography (GC), gas chromatography-mass spectrometry (GC-MS) [1][2][3][4][5] and high performance liquid chromatography (HPLC) [6][7][8][9][10][11] have been reported for the simultaneous determination of progesterone, 17-hydroxyprogesterone and other 3-keto steroids. HPLC is widely used because simple extraction and derivatization methods can be employed.…”

“…Using HPLC, each steroid was separated on a normal-or reversed-phase column after prelabeling with 1-dimethylaminonaphthalene-5-sulfonylhydrazine (dansylhydrazine). [6][7][8][9][10][11] These steroids were detected by fluorescence [6][7]10,11 or chemiluminescence detection. 8,9 We have developed an HPLC method for monitoring estrogens [12][13][14] in biological fluids from pregnant women.…”

“…but the detection limits of reported HPLC methods with dansylhydrazine were 60-4000 ng ml 21 in serum or plasma. [6][7][8][9][10][11] Hence it was necessary to improve the sensitivity after prelabeling for monitoring progesterone and 17-hydroxyprogesterone in serum from pregnant women. We therefore studied new pre-labeling reagents and HPLC conditions.…”