No abstract

No abstract

No abstract

Original PaperHigh performance liquid chromatography for the determination of glucosamine sulfate in human plasma after derivatization with 9-fluorenylmethyl chloroformateIn this study, we developed a simple, rapid, sensitive, and reliable method for the determination of glucosamine sulfate in human plasma, which was based on derivatization with 9-fluorenylmethyl chloroformate (FMOC-Cl) followed by reverse-phase HPLC-FLD. For the first time, FMOC-Cl was introduced into derivatization of glucosamine sulfate in human plasma. The amino groups of glucosamine sulfate and vertilmicin sulfate (the internal standard) were trapped with FMOC-Cl to form glucosamine-FMOC-Cl and vertilmicin-FMOC-Cl adducts, which can be very suitable for HPLC-FLD. Precipitation of plasma proteins by acetonitrile was followed by vortex mixing and centrifugation. Chromatographic separation was performed on a C 18 column (DIAMONSIL 15064 mm id, 5 lm) with a mobile phase gradient consisting of acetonitrile and water at a flow-rate of 1 mL/min. The retention times of glucosamine-FMOC-Cl and vertilmicin-FMOC-Cl adducts were 8.9 and 21.2 min, respectively. This method was shown to be selective and sensitive for glucosamine sulfate. The limit of detection was 15 ng/mL for glucosamine sulfate in plasma and the linear range was 0.1 -10 mg/mL in plasma with a correlation coefficient (r) of 0.9999. The relative standard deviations (RSDs) of intra-day and inter-day assays were 5.2 -8.1% and 6.1 -8.5%, respectively. Extraction recoveries of glucosamine sulfate in plasma were greater than 90%. The validated method was successfully applied to the determination of glucosamine sulfate in human plasma samples.

A liquid chromatography-electrospray ionization mass spectrometry (LC-ESI-MS) method was developed and validated for the assay of glucosamine sulfate in human plasma. Plasma proteins were precipitated by acetonitrile, followed by vortex mixing and centrifugation. The supernatant was transferred and derivatized with phenyl iso-thiocyanate in acetonitrile at 60 degrees C for 40 min. Chromatographic separation was performed on a C(18) column (Inertsil ODS-3 150 x 2.1 mm i.d., 5 microm, JP) with a mobile phase gradient consisting of 0.2% acetic acid (aqueous) and methanol at a flow-rate of 0.3 mL/min. MS detection using electrospray ionization (ESI) as an interface was used in single ion monitoring mode to determine positive ions at m/z 297. This method was shown to be selective and sensitive for glucosamine sulfate. The limit of detection was 35 ng/mL for glucosamine sulfate in plasma and the linear range was 0.1-20 microg/mL in plasma with a correlation coefficient (r) of 0.9991. The relative standard deviations (RSDs) of intra-day and inter-day assays were 8.7-11.4 and 9.8-12.6%, respectively. Extraction recoveries of glucosamine sulfate in plasma were greater than 73%. This method proved to be simple, reproducible and feasible for pharmacokinetic studies of glucosamine sulfate in healthy volunteers after a single oral administration (1500 mg). The pharmacokinetic parameters and relative bioavailabilities were investigated for both domestic glucosamine sulfate tablet and capsule preparations compared with an imported capsule product.