Adsorption hierarchy of surfactants and polymers to a damaged hair model: effect of composition, order and polymer size.

A comprehensive understanding of chemical interactions at the surface of hair represents an important area of research within the cosmetic industry and is essential to obtain new products that exhibit both performance and sustainability. This paper aims at contributing to this research by applying a combination of surface techniques (neutron reflectometry, quartz-crystal microbalance and atomic force microscopy) to study adsorption of surface active ingredients onto hair-mimetic surfaces. The surface of hair is not homogeneous due to chemical and physical damage, and this work focuses on partly damaged hair models, in which both hydrophobic and charged moieties are present.

Roles of Polymer Concentration and Ionic Strength in the Deposition of Chitosan of Fungal Origin onto Negatively Charged Surfaces.

This study examines the potential of fungal chitosan derived from as a sustainable alternative to traditional petrochemical-based ingredients in cosmetic products. Specifically, the research examines the solubility of fungal chitosan in aqueous solutions of varying ionic strength and its adsorption onto negatively charged surfaces that mimic human hair keratin. The adsorption behavior, water content, and frictional properties of chitosan films were evaluated using a quartz crystal microbalance with dissipation monitoring and a surface force apparatus (SFA).

Mimicking the hair surface for neutron reflectometry.

The surface of human hair is normally hydrophobic as it is covered by a lipid layer, mainly composed of 18-methyleicosanoic acid (18-MEA). When the hair is damaged, this layer can be partially or fully removed and more hydrophilic, mainly negatively charged surfaces are formed with a wide variety of physical and chemical characteristics. The cosmetic industry is currently embracing the opportunity of increasing the sustainability of their hair-care products whilst improving product performance.

The Complicated Case of Staphylococcus aureus Bacteremia Associated With Delayed-Onset Prosthetic Joint Infection: A Case Report and Review of Management Strategies.

(), an opportunistic Gram-positive bacterium, is notorious for causing a plethora of clinical diseases. While it does not typically infect healthy skin, infections are prevalent in both community-acquired and hospital-acquired settings. Rheumatoid arthritis (RA), a chronic autoimmune disease characterized by joint inflammation and progressive bone erosion, can be managed medically and, in moderate to severe cases, surgically through arthroplasty.