The protein adsorption properties and biocompatibility of common soft materials often cannot satisfy the functional requirements in the field of cell culture and biological diagnosis. The preparation of a polyelectrolyte coating on the surface of materials is an effective means to solve this problem. Owing to its excellent cell affinity and bioadhesion, chitosan has become an excellent carrier in the biomedical field. Therefore, a polyelectrolyte coating of polydopamine and polyacrylic acid was prepared by polymerization and codeposition under acidic conditions, and the self-assembly of chitosan was carried out on the polyelectrolyte coating to investigate the factors that affect the protein adsorption performance. The study demonstrated that the chitosan coating has outstanding wetting performance, with a 57.54% reduction in the water contact angle after modification. Furthermore, protein adsorption on the original surface was significantly improved. The surface protein adsorption capacity increased with increasing chitosan content, and the maximum adsorption capacity was 4.43 times greater than that of the uncoated sample. Additionally, the chitosan coating had remarkable biocompatibility. The survival rate of mouse osteoblasts cultured on the modified material was 35% greater than that of the original material, and cell proliferation was promoted. The fabrication tactic in this study allows the preparation of chitosan coatings on the polyelectrolyte coating of various material surfaces with controllable surface properties and provides new insights into the preparation tactic of biological coatings for protein adsorption.

Due to the increasing risk of obesity and cardiovascular diseases caused by high-fat diets, low-fat foods have become a priority demand for consumers’ health. However, the smoothness perception and scientific assessment methods of the existing low-fat foods should be improved. In this study, three food emulsions were prepared, and their lubrication characteristics, sensory evaluation of smoothness, and electroencephalogram (EEG) signals were assessed to preliminarily investigate the effects of food emulsion components on their above characteristics. The results showed that fat substitute (FSU) and fat could significantly reduce coefficient of friction (CoF) of the food emulsions, with average CoF reduced by 28% and 63% compared to the original food emulsions. In addition, fat-enriched food emulsions continued to exhibit excellent lubrication characteristics after adding artificial saliva, with an average CoF reduced by 31.1% compared to that of the food emulsions without artificial saliva. Both FSU and fat improved the smoothness of food emulsions, and the lubricating properties of fat were more pronounced, with fat-enriched food emulsion which could provide a substantial improvement in smoothness compared to the fat-free food emulsion. Comparison of subjects’ EEG signals revealed that food emulsion with lower CoF and higher smoothness triggered higher P3 amplitudes and longer latencies. These findings provide better insights into the scientific evaluation of food texture and the development of low-fat foods.