Preparation of Cholesteryl-Modified Aminated Pullulan Nanoparticles to Evaluate Nanoparticle of Hydrophobic Degree on Drug Release and Cytotoxicity

The formation of nanoparticles (NPs) and surface properties such as size and charge are affected by the amphiphilic property of polymer, which is vital for evaluating their function. Here, we synthesized cholesteryl-modified aminated pullulan polymers (CHPNs) with different amounts of cholesterol succinate (CHS). We characterized the three hydrophobically modified polymers (CHPN1, CHPN2, and CHPN3) (CHS: Pu‐NH2=1/5,2/5,3/5) by Fourier transform infrared spectrometry. Dynamic light scattering (DLS) was used to measure particle size and zeta potential of CHPN NPs. The particle sizes of the three NPs CHPN1, CHPN2, and CHPN3 were 178.0, 144.4, and 97.8 nm, respectively. The particle size was related to the cholesteryl substitution of polymers to a certain extent: the stronger the hydrophobicity, the smaller the particle size. In 48 h, the drug release for CHPN3 and CHPN1 NPs was 57.8% and 72.7%. Thus, the NPs showed good sustained drug release: the greater the degree of hydrophobic substitution, the better the sustained release. The cytotoxicity findings were reversed: CHPN1 NPs, with low hydrophobic substitution, showed the best inhibition of Lewis lung cancer cells.

Probing the adsorption/desorption of amphiphilic polymers at the air–water interface during large interfacial deformations

Large interfacial compressions and dilations enable to probe the interfacial anchoring of hydrophobic grafts of hydrophobically modified polymers.

Influence of Hydrophobe, Surfactant and Salt Concentrations in Hydrophobically Modified Alkali-Soluble Polymers Obtained by Solution Polymerization

The viscosity of hydrophobically modified alkali-soluble polymers to different hydrophobic macromonomer concentrations in the presence of various concentrations of anionic surfactant and salt were investigated. Associative polymers containing both ionic sites and small number of hydrophobic groups were prepared, and their thickening properties in aqueous solution were investigated. Solution polymerization was used for obtained the different polymers. Relationships between hydrophobe, sodium dodecyl sulfate (SDS) and salt (NaCl) concentrations are proposed. Owing to the competition between attractive hydrophobic interaction and repulsive electrostatic interactions, such hydrophobically modified polymers exhibit various rheological behaviors in aqueous solution depending on hydrophobic macromonomer, SDS and NaCl concentrations.

CO2-responsive self-healable hydrogels based on hydrophobically-modified polymers bridged by wormlike micelles

A versatile and simple strategy is proposed to design CO2-responsive self-healable hydrogels based on hydrophobically-modified polymers bridged by worm like micelles.

Cleansing Formulations That Respect Skin Barrier Integrity

Surfactants in skin cleansers interact with the skin in several manners. In addition to the desired benefit of providing skin hygiene, surfactants also extract skin components during cleansing and remain in the stratum corneum (SC) after rinsing. These side effects disrupt SC structure and degrade its barrier properties. Recent applications of vibrational spectroscopy and two-photon microscopy in skin research have provided molecular-level information to facilitate our understanding of the interaction between skin and surfactant. In the arena of commercial skin cleansers, technologies have been developed to produce cleansers that both cleanse and respect skin barrier. The main approach is to minimize surfactant interaction with skin through altering its solution properties. Recently, hydrophobically modified polymers (HMPs) have been introduced to create skin compatible cleansing systems. At the presence of HMP, surfactants assemble into larger, more stable structures. These structures are less likely to penetrate the skin, thereby resulting in less aggressive cleansers and the integrity of the skin barrier is maintained. In this paper, we reviewed our recent findings on surfactant and SC interactions at molecular level and provided an overview of the HM technology for developing cleansers that respect skin barrier.