Binary Pluronics based mixed micellar systems: Effective solution for improved solubilization of Biochanin A

The present work was carried out to appraise the solubilization of Biochanin (BCA), a natural hydrophobic drug in pure Pluronics (P84, P123 and F127) as well as binary mixed micelles (P84-P123 and F127-P123) followed by an interactional study using various state of art techniques. The critical micelle concentration (CMC) of binary mixtures P84-P123 and F127-P123 was found to be significantly lower than pure Pluronics justifying the candidature of mixed micelles (MMs) as a better solubilizer for BCA. UV-visible studies revealed the enhanced solubility of BCA in P84-P123 (1:2) MMs (3.51 +/- 0.087 mg/mL) and F127-P123 (1:2) MMs (2.94 +/- 0.046 mg/ mL) as compared to micelles of pure Pluronics (10% w/v), P84 (2.25 +/- 0.039 mg/mL) and F127 (1.12 +/- 0.036 mg/mL). Differential pulse voltammetry (DPV) results demonstrated significantly superior binding of BCA with P84-P123 (1:2) MM (Ka = 2.60 x 105 M-1) as compared to pure P84 (Ka = 1.415 x 105 M-1). Mixed micellization (P84-P123 (1:2)) leads to increase in micellar hydrodynamic diameter (Dh = 16.09 nm) as compared to pure Pluronic P84 micelles (Dh = 15.71 nm) which was further amplified (Dh = 17.69 nm) after BCA loading. Different formulations of pure and MMs were subjected to in vitro drug release and MMs were found to slow down BCA release as compared to pure Pluronics (P84, P123). The results obtained in this study proved that P84-P123 (1:2) MMs are superior and more effective for the solubilization of BCA than pure and other MMs. Thus, the examined MMs hold the potential for advancing the development of solubilization techniques for other hydrophobic drugs with significant pharmacological value.