Determination of TNBG in Plasma by RP-HPLC

A specific and simple high-performance liquid chromatographic(HPLC) method was developed for the determination of TNBG in plasma with UV-visible detection.HPLC separation on Lichrospher C18(4.6 mm×250 mm,5 μm) was carried out with an isocratic mobile phase of 90% methanol in 100 mL methanol-deionized water(pH 6.5),containing 0.1% triethyl amine and detection at 260 nm.The retention time of TNBG was less than 6 min.The linearity was good over the concentration range 1-20 μg/mL(r≥ 0.995).The recoveries were in the range 98.1-104.5%(n=5),and the inter-and intra-day RSD were less than 8.0%.The detection limit was 0.4 μg/mL.This novel and rapid method can be employed in a routine clinical setting.