水飞蓟宾在不同介质中平衡溶解度和表观油水分配系数的测定

Determination of Equilibrium Solubility of Silibinin in Various Medium and Its Apparent Oil/Water Partition Coefficient

目的测定水飞蓟宾在水和表面活性剂溶液中的平衡溶解度以及在正辛醇-水/缓冲液体系中的表观油水分配系数。方法采用高效液相法测定了水飞蓟宾在水、缓冲液和表面活性剂溶液中的浓度,采用摇瓶法测定了水飞蓟宾的表观油水分配系数。结果37℃水飞蓟宾在水中的平衡溶解度为51.06 mg.L-1,在碱性缓冲液中溶解度增大;聚山梨酯80和泊洛沙姆188对水飞蓟宾有较强的增溶能力;水飞蓟宾的表观油水分配系数为989.0。结论水飞蓟宾的水溶性较差,提高其口服制剂的溶出度可能会提高其生物利用度。

OBJECTIVE To determine the equilibrium solubility of silibinin in various surfactant solutions and its partition coeffieients for the n-octanol-water/buffer solution systems. METHODS A high performance liquid chromatography method was established and used to detect the concentration of silibinin in water, buffer solutions and surfactant solutions; the partition coefficients for the n-octanol-water/buffer solution systems of silibinin were determined by shaking flask method. RESULTS The equilibrium solubility of silibinin in water was 51.06 mg·L^-1 at 37 ℃ and had higher values in basic buffer solutions; polysorhate 80 and poloxamer 188 were good solubilizers for silibinin; Papp of silibinin was 989.0. CONCLUSION Silibinin is a hydrophobic drug; increasing the dissolution rate of silibinin from its oral drug delivery system may have the possibility to enhance its bioavailability.