Determination of Solubility and Apparent Oil/Water Partition Cofficient of Salicylic Acid by RP-HPLC
10.3870/j.issn.1004-0781.2017.02.017
- VernacularTitle:反相高效液相色谱法测定水杨酸的平衡溶解度及表观油水分配系数
- Author:
Xifeng TENG
;
Feng WANG
;
Kunrong LI
;
Shanshan CHEN
;
Peng YE
;
Lin HE
;
Guoquan LI
- Keywords:
Salicylic acid;
Equilibrium solubility;
Apparent partition coefficient;
Chromatography,high performance liquid
- From:
Herald of Medicine
2017;36(2):186-189
- CountryChina
- Language:Chinese
-
Abstract:
Objective To determine equilibrium solubility and apparent partition coefficient of salicylic acid at 25 ℃,and to provide a theoretical basis for design and preparation of its formulation.Methods Equilibrium solubility and apparent partition coefficient (Papp) of salicylic acid were respectively investigated in water,hydrochloric acid solution (pH 1.0) and phosphate buffer solution system (pH 2.0,3.0,4.0,5.0,6.0,7.0,7.8) at 25 ℃.The shake flask method and HPLC were used.The column was Waters C18 (4.6 mm ×250 mm,5 μn) with the mobile phase as methanol-0.1% phosphoric acid water (47:53).The column temperature was room temperature.The flow rate was 1.0 mL·min-1.The detection wavelength was 270 nm and injection volume was 20 μL.Results Equilibrium solubility of salicylic acid was (2.205 ±0.020) mg·mL-1 at 25 ℃ in Water and its Papp was (6.18 ±0.08).The solubility were (1.169 × 10-3 ±7.40 × 10-6),(2.250 ±0.010),(2.410±0.010),(2.694 ±0.003),(5.208 ±0.010),(5.826 ±0.006),(6.255 ±0.030),(3.353 ±0.070) mg·mL-1,respectively,at hydrochloric acid solution (pH 1.0) and phosphate buffer solution system (pH 2.0,3.0,4.0,5.0,6.0,7.0,7.8),and the corresponding Papp were (16.39 ±0.19),(4.23 ±0.07),(6.03 ±0.11),(5.56 ±0.10),(1.25 ±0.01),(0.27 ± 0.001),(0.08 ± 0.001) and (0.07 ± 0.002),respectively.Conclusion The solubility of salicylic acid increases and its oil-water partition coefficient declines with pH value increasing.Salicylic acid is slightly soluble in water and oil.It belongs to Class Ⅳ drug in Biopharmaceutics Classification System (BCS).