Pharmacokinetic study on spinosin in rat plasma after oral administration of suanzaoren extract at a single dose.
OBJECTIVE
To study the pharmacokinetics of spinosin in rat plasma after oral administration of Suanzaoren extract using sulfamethoxazole (SMZ) as internal standard by RP-HPLC method.


METHODS
Plasma samples were deproteined with acetonitrile, followed by evaporation of the acetonitrile to dryness. The residual was then resolved in mobile phase and HPLC separation was achieved on a Hypersil C18 (5 microns, 200 mm x 4.6 mm ID) column at 35 degrees C. The mobile phase consisted of acetonitrile-water-acetic acid (15:85:1) at a flow rate of 0.7 mL.min-1. The UV detection wavelength was set at 334 nm.


RESULTS
The calibration curve was shown to be linear over the range from 18.1 to 903.5 micrograms.L-1 (r2 > or = 0.995). Mean recovery was 94.5%. Within-day and between-day precisions RSD were less than 9.0%. The limit of quantitation was 18.1 micrograms.L-1. The plasma spinosin was stable at -20 degrees C.


CONCLUSIONS
The simple, sensitive and accurate HPLC method developed has been applied to determine the pharmacokinetics of spinosin in rat plasma after having taken Suanzaoren extract at a single dose.
D000284:Administration, Oral; D000818:Animals; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D004365:Drugs, Chinese Herbal / Q000008:administration & dosage / Q000302:isolation & purification / Q000493:pharmacokinetics*; D005419:Flavonoids / Q000097:blood* / Q000302:isolation & purification / Q000493:pharmacokinetics; D010946:Plants, Medicinal / Q000737:chemistry*; D051381:Rats; D017208:Rats, Wistar; D012639:Seeds / Q000737:chemistry; D031957:Ziziphus / Q000737:chemistry*
D004365:Drugs, Chinese Herbal; D005419:Flavonoids; C055669:spinosin