| Liquid-mass spectrometry(LC-MS)has become a useful tool for trace component analysis due to its high sensitivity and high selectivity.However,mass spectrometry chiral derivatization reagents are still in development compared to fluorescent chiral derivatization reagents.In many cases,the pharmacological and pharmacokinetics of the two isomeric drugs are sometimes significantly different.The pre-column derivatization method is the primary method for the separation and detection of chiral compounds.Non-steroidal anti-inflammatory drugs(NSAIDs)are widely used in the treatment of multiple inflammatory diseases.Most of them have a chiral center,and its two enantiomers’ in vivo pharmacological activity,metabolic processes and toxic reactions are significantly different.The severe side effects caused by administrating the racemic drugs.Since most of the NSAIDs have carboxyl functional groups,in this study we developed novel mass spectrometric chiral derivatization reagents that are capable to detect two enantiomers by chiral resolution and high sensitivity.Firstly,(4-Carboxybutyl)triphenylphosphonium bromide(TPPP)and(S)-3-(Boc-amino)pyrrolidine(PR-Boc-N)were used as a precursor to synthesize a novel mass spectrometric derivative reagent with positive charge structure for targeting carboxyl chiral compounds,N-[1-Oxo-5-(triphenylphosphonium)pentyl]-(S)-3-amino pyrrolidine(OTPA).In order to evaluate the chiral separation efficiency of this reagent,four NSAIDs:Ibuprofen(IBU),naproxen(NAP),ketoprofen(KET),Loxoprofen(LOX)and two chiral carboxy compounds 2-phenylbutyric acid(PBA),2-phenylpropyl acid(PPA)were used to derivatize with OTPA,The derivatized products were chiral resolution and methodological study by HPLC-UV and C18 reversed-phase columns,and the human plasma and tablets were used to carry out standard addition recovery experiments.The resolution of each diastereomer derivative products was 1.54～2.23 under optimized separation conditions with 0.1%formic acid acetonitrile-water as the mobile phase,which achieved good chiral separation.The limits of detection were 14～76 pmol,limit quantitative of 50～343 pmol.For the derivatization products in the range of 0.05～1.0 mmol/L,a good linearity was obtained from all the carboxylic acids(R2≥0.997).Intra-day and Inter-day precisions are less than 6.77%.The recovery rate of plasma from healthy volunteers ranged between 88.58%and 104.66%and RSD was less than 7.86%.Two kinds of commercially available tablets were tested for the main ingredients,the recoveries of R,S-IBU(ibuprofen dispersant)and S-NAP(naproxen tablet)were 94.78%～95.40%and 93.71%～94.88%,respectively.The contents of the two tablets of active ingredients were measured and compared with the content of the drug specification.The content of R-and S-IBU in the ibuprofen dispersible tablets was 0.235±0.0018 mg/mg and 0.232±0.0012 mg/mg,respectively.The content of S-NAP in naproxen tablets was 0.864±0.0074 mg/mg.Accuracy is greater than 96.49%.In this study,a new mass derivatization reagent OTPA for the identification of carboxy chiral compounds with a triphenylphosphine positively charged structure was synthesized for the first time.And using the present method to high sensitivity detect chiral compounds with carboxyl functional groups in human plasma and tablets,so it can be used for pharmacokinetic studies of chiral drugs in biological samples and quantitative analysis of chiral carboxy metabolites.A novel chiral mass spectrometry reagent is provided for the separation and quantification of chiral carboxy compounds. |
