Bending mattress and antibacterial effect of TiO2/nAg/chitosan-nanoparticle-applied intelligent patient bed

Abstract

In Taiwan, the hot and humid weather easily leads to a bedsore problem in bedridden patients. Moreover, general patient beds are inconvenient for elderly people with reduced mobility. In this study, to develop a biocompatible mattress that can assist the turning and bending of the elderly and hence reduce the incidence of bedsores, we have proposed an antibacterial and bendable mattress. On the basis of the advice of doctors, we chose titanium dioxide (TiO2), nanosilver (nAg), and chitosan antibacterial nanoparticles to produce the mattress. By using carbon fibers, the weight of the bed frame can be decreased. The mechanical properties of the mattress and the wear resistances of various foaming formulations and coating materials were determined. The foam material was produced by two methods, namely, the semi-prepolymer method and the one-step method. Moreover, the Ag/TiO2 powder was experimentally proven to endow excellent biocompatibility and mechanical properties to the preferred foam materials. Silver nitrate was added to prepare the Ag/TiO2 powder by sintering at 600 °C. The particle size of the Ag/TiO2 powder was about 1185 nm before sintering. After sintering, the particle size was reduced to 958.3 nm, and the atomic percentage of Cl was 0.15%. Sintering clearly improved the antibacterial effect of the Ag/TiO2 powder to 99%, which is higher than those of pure TiO2 and pure Ag/TiO2 powders. To improve the overall properties of the mattress, various hard materials were added to the bottom of the polyurethane film. The rebound rates of the mattresses with various hardnesses were measured by a physician to obtain the best mattress.