Investigating the effect of a simplified perfume accord and dilution on the formation of mixed-surfactant microemulsions

Rhodiola rosea polysaccharides-based nanoparticles loaded with DOX boosts chemo-immunotherapy for triple-negative breast cancer by re-educating tumor-associated macrophages

Efficient encapsulation and tumor targeting ability are the key issues for hydrophobic drugs delivery vectors in cancer therapy. In the current study, Rhodiola rosea polysaccharides (RHPs) serve as an immunoactive vector for drug delivery with tumor-associated macrophages (TAMs) modulating ability and typical structural characteristics. Firstly, Folic acid (FA) and stearic acid (SA) were chemically modified to the backbone of RHPs to obtain the self-assemble and tumor targeting behaviors. Then, the hydrophobic drug (Doxorubicin, DOX) was encapsulated in the RHPs derivatives (FA-RHPs-SA) with high efficiency. Moreover, the optimal formed DOX@FA-RHPs-SA were around 196 nm with uniform size distribution and a pH-sensitive release capacity in different acidic conditions. In vitro experiments demonstrated that DOX@FA-RHPs-SA could efficiently uptake by tumor cells. Furthermore, the modulatory function of the FA-RHPs-SA on RAW264.7 macrophages was also demonstrated in the transition from M0 to M1 phenotypes, and the M2 differentiated into the M1. Finally, in vivo antitumor study revealed that the inhibitory effect of DOX@FA-RHPs-SA was superior to the DOX monotherapy treatment, and the new preparation worked synergistically by inducing tumor cell apoptosis and modulating immune cell function. In summary, this study describes a RHPs-based hydrophobic delivery vector and achieved an additional helpful antitumor effect by modulating TAMs.

Structural alterations of branched versus linear mixed-surfactant micellar systems with the addition of a complex perfume mixture and dipropylene glycol as cosolvent

Personal care products commonly contain perfume mixtures, consisting of numerous perfume raw materials (PRMs), and cosolvents. The lipophilicity and structure of an individual PRM is known to affect its localization within the surfactant self-assembly as well as the micellar geometry. However, because multiple PRMs are used in formulations, significant intermolecular interactions between the PRMs and between the PRMs and the surfactant tail may also influence the location of the PRMs and their effects on the self-assembly. Herein, two anionic/zwitterionic mixed-surfactant systems (sodium trideceth-2 sulfate (ST2S)/cocamidopropyl betaine (CAPB) and sodium laureth-3 sulfate/CAPB) were formulated with a cosolvent (dipropylene glycol (DPG)) and 12 PRMs of varying structures and lipophilicities. This 12 PRM accord is simpler than a fully formulated perfume but more complex than a single perfume molecule. The geometric variations in the self-assemblies were evaluated using small-angle neutron scattering, perfume head space concentrations were determined using gas chromatography-mass spectrometry, and perfume localization was identified using NMR spectroscopy. The addition of the perfume accord caused enlargement of the micelles in both surfactant systems, with a greater change observed for ST2S/CAPB formulations. Furthermore, the addition of DPG to ST2S/CAPB resulted in micelle shrinkage. The micelle geometries and PRM localization in the micelles were affected by the degree of branching in the surfactant tail.

Personal care products commonly contain perfume mixtures, consisting of numerous perfume raw materials (PRMs), and cosolvents. Depending on the molecular structures of the additives and surfactants, the geometry of the colloidal structures can be affected.

Effects of a Multicomponent Perfume Accord and Dilution on the Formation of ST2S/CAPB Mixed-Surfactant Microemulsions

Perfume mixtures contain perfume raw materials (PRMs) with varying structures and hydrophobicities, which influence PRM localization within a surfactant-based formulation and thereby affect the phase behavior. In rinse-off products, the addition of water can further affect the phase behavior. In this study, a mixture of 12 PRMs was used as the oil phase in an aqueous system consisting of sodium trideceth-2 sulfate as a primary surfactant, cocamidopropyl betaine as a cosurfactant, and dipropylene glycol as a cosolvent. A series of phase diagrams were constructed with increasing water content, simulating the use conditions for rinse-off products, to determine how the phase boundaries shift with dilution. Using these phase diagrams, the compositions of interest in the micelle without perfume, micelle with perfume, microemulsion, and micelle-microemulsion transition regions were identified at each dilution level. The structural changes were probed through combined small-angle neutron scattering (SANS) and cryo-transmission electron microscopy analyses. The SANS results showed that ellipsoidal micelles were maintained as the perfume content and the dilution level increased. With ≥50 wt % water, increasing the perfume content increased the micelle volume. Interestingly, a higher rate of volume increase was observed at ≥70 wt % water. Notably, the volumes of the micelles with and without perfume increased steadily with dilution, whereas the volumes of the assemblies in the transition region and the microemulsion region increased more rapidly once diluted to 70 and 80 wt % water, respectively.