Co-micellization conduct and structural dynamics of block copolymers in water and salt solution environment for drug solubilization enhancement

Salt induced micellization conduct in PEO–PPO–PEO-based block copolymers: a thermo-responsive approach

“…10 presents the broad orange-OT spectra with absorbance maxima at ∼490 nm due to low energy π–π* excitation which matches well with the reported works. 5,24 As the dye incorporates into the core–shell micelles through the solubilization process, enhancements in the CMC and micelle structure can significantly impact Pluronics® capacity. 73 According to the order of increasing hydrophobicity of Pluronics®, a shift towards the absorbance peak suggests the dissolution of orange-OT within the core–shell micelle.…”

“…The wave vector transfer is defined as Q (= 4πsin θ /2)/ λ , where λ represents the incident neutron wavelength and θ represents the scattering angle. 21,24,53,54,59…”

“…Notably, the second relaxation process exhibits an activation limit that significantly slow down as the molecular weight of the copolymer increases. Thus, the aggregation processes of these BCPs in aqueous solution is an intriguing research area and have been extensively investigated, considering the factors such as temperature and copolymer concentration, hydrophilic–lipophilic balance (HLB) range especially when understanding the behavior of micelles in the presence of various additives including ionic/nonionic surfactants, 6,14–22 salts, 5,23,24 denaturants, 12,25–27 alcohols, 17,28,29 ionic liquids, 30–32 and others 33–35 as it plays a crucial role in defining their applications).…”

“…For example, surfactants, denaturants, alcohols, and similar compounds act as salting in agents, while NaCl, KCl, and similar salts act as salting-out agents. 5,23,24,39–41 In general, adding salt to BCPs facilitate the disruption of hydrogen bonds between the copolymer and water molecules, leading to enhanced PPO–PPO hydrophobic interactions. Consequently, the process of micellization occurs earlier and at a lower temperature when salt is present compared to its absence.…”

“…Consequently, the process of micellization occurs earlier and at a lower temperature when salt is present compared to its absence. 19,21,24 Additional salts, particularly powerful chaotropic compounds such as KI, NaSCN, KBr, and NaNO 3 can further decrease the CP of the BCPs. Dehydration of the PEO shell and increased hydrophobicity of the PPO blocks enhance the overall hydrophobicity of the copolymer chains, thereby promoting early micellization.…”