Unusual solubilization capacity of hydrophobic drug olanzapine in polysorbate micelles for improved sustained drug release

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 × 105 M-1) as compared to pure P84 (Ka = 1.415 × 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.

Molecular insights into the aggregation and solubilizing behavior of biocompatible amphiphiles Gelucire® 48/16 and Tetronics® 1304 in aqueous media

A comparative analysis of the micellar and solubilizing properties of two polyethylene glycol (PEG)-based amphiphilic biocompatible excipients: Gelucire® 48/16 (Ge 48/16) and Tetronics® 1304 (T1304), in the presence and absence of salt, was conducted. As there is a dearth of research in this area, the study aims to shed light on the behavior of these two nonionic surfactants and their potential as nanocarriers for solubilizing pharmaceuticals. Various techniques such as cloud point (CP), dynamic light scattering (DLS), small-angle neutron scattering (SANS), Fourier transform infrared spectroscopy (FT-IR), UV spectrophotometry, and high-performance liquid chromatography (HPLC) were employed. The solubility of quercetin (QCT), a flavonoid with anti-inflammatory, antioxidant, and anti-cancer properties, was evaluated and the interaction between QCT and the micellar system was examined. The analysis revealed the occurrence of strong interactions between QCT and surfactant molecules, resulting in enhanced solubility. It was observed that the micellar size and solubilizing ability were significantly improved in the presence of salt, while the CP decreased. Ge 48/16 exhibited superior performance, with a remarkable increase in the solubility of QCT in the presence of salt, suggesting its potential as an effective nanocarrier for a range of pharmaceutics, and yielding better therapeutic outcomes.

Redox-sensitive self-assembled micelles based on low molecular weight chitosan-lipoic acid conjugates for the delivery of doxorubicin: Effect of substitution degree of lipoic acid

Amphiphilic low molecular weight chitosan-lipoic acid (LC-LA) conjugates with different degrees of substitution (DS) of LA were synthesized by N, N'‑carbonyldiimidazole (CDI) catalysis to self-assemble into redox-sensitive micelles. Critical micelle concentration (CMC), size, zeta potential, biocompatibility and redox-sensitive behavior of blank micelles were investigated. The results indicated that blank micelles with low CMC, nanoscale size and positive zeta potential showed excellent biocompatibility and redox-sensitive behavior. Doxorubicin (Dox) loaded micelles were prepared by encapsulating Dox into blank micelles. The loading ability, trigger-release behavior, antitumor activity and cellular uptake of Dox loaded micelles were studied. The results demonstrated that Dox loaded micelles with superior loading ability exhibited redox-trigger behavior, strong antitumor activity and increased cellular uptake efficiency against A549 cell. Besides, the effect of DS of LA on above properties was estimated. An increase in DS of LA reduced the CMC and cumulative release amount of Dox, but improved the loading efficiency, antitumor activity, and cellular uptake of Dox loaded micelles, which resulted from stronger interaction of hydrophobic groups in micelles with the DS of LA increased. Overall, self-assembled LC-LA micelles with good biosecurity and redox-sensitive behavior hold promising application prospects in Dox delivery and improving cancer therapeutic effect of Dox.