Orthopedic Antibacterial Coating
Orthopedic Antibacterial Coating – Spray Coater Machine – Cheersonic
The aging of the population has increased the pressure on orthopaedic medical treatment. According to statistics, there are more than 5 million cases of fracture implants in China every year. Implant infection is one of the serious complications after surgery, which is difficult to prevent. Although doctors have made various surgical preparations to prevent bacterial contamination before surgery, postoperative infection is still unavoidable. In order to reduce the occurrence of postoperative infection, in recent decades, people have made great progress in the research of aseptic technique, sterile environment and preventive application of antibiotics during operation. Antibacterial implant materials have become an effective means to reduce postoperative infection. in the medical field.
Due to medical needs, implant surfaces are often required to have certain properties, but these can lead to the development of associated infections on biomaterial surfaces. Therefore, coating the surface of endoplants to improve the antibacterial properties of the surface has become a research hotspot.
Antibacterial coating refers to the process of coating various materials with antibacterial function on the substrate through spraying, sol-gel, composite plating, ion implantation, magnetron sputtering and other processes. Since the antibacterial coating will be gradually worn away with application, it cannot maintain long-term antibacterial effect, so how to enhance the binding force of the antibacterial coating and the substrate, and obtain good antibacterial properties, biocompatibility, high wear resistance, durability is the key question of current research.
According to the coating composition, it can be divided into antibiotic coating, non-antibiotic organic antibacterial agent coating, inorganic antibacterial agent coating, anti-adhesion coating and antibacterial bioactive polymer coating.
1. Anti-adhesion coating
The anti-adhesion coating can change the number and reproduction of bacteria on the surface of the implant by changing the roughness, hydrophilicity, electrical conductivity and other characteristics of the implant surface, so as to achieve antibacterial purposes.
Surface-modified anti-adhesion coatings are a relatively simple and economical way to eliminate bacterial adhesion through implant surface properties, such as UV-irradiation treatment to improve osteoconductivity and antibacterial properties of titanium implants. Experiments have shown that the surface modification of implants can improve the antibacterial properties of implants, which is also a new research direction of antibacterial coatings.
2. Polymer coating
The polymer titanium alloy coating can significantly reduce the adhesion of Staphylococcus aureus and Staphylococcus epidermidis, has good antibacterial ability and improves bioactive molecules. These coatings achieve antibacterial effects by blocking the adhesion of bacteria to plants and preventing the formation of biofilms.
Bioactive molecules such as chitosan and hyaluronic acid have antibacterial and bactericidal properties. Chitosan has various properties such as biocompatibility, biodegradation, physiological inertness, antibacterial properties, and antifungal properties. When chitosan is bound to titanium alloy, it can promote the attachment and growth of bone cells, and compared with calcium phosphate and other coatings, chitosan has a better effect on promoting osseointegration; chitosan also The surface of nanoparticles can be modified to improve their antibacterial properties and reduce cytotoxicity; in the mixed calcium phosphate/chitosan titanium alloy coating, chitosan can improve the performance of the calcium phosphate coating without compromising its good adhesive strength. The coating has been shown to provide a good interface for local bone marrow stromal cell proliferation and osteoblast differentiation. The antibacterial properties of bioactive polymer coatings such as chitosan have been widely recognized, and the specific properties require further detailed study. Polymer coating has high research value, but its mechanism and process in vivo need to be further studied.
3. Antibiotic antibacterial coating
Antibiotic coatings are the early research direction of antibacterial materials, which have the advantages of fast antibacterial effect, long duration and low toxicity. Common antibiotics due to antibacterial coatings include gentamicin, cephalosporin, minocycline, carbenicillin, amoxicillin, tobramycin and vancomycin, etc., but they still face many difficulties in clinical application. : How to select antibiotics with strong bacterial sensitivity to be loaded on the surface of internal plants, how to make them have a longer effective sustained release time of antibiotics, and how to prevent the concentration of antibiotics from being released below the minimum inhibitory concentration, etc.
4. Non-antibiotic organic antibacterial agent coating
Compared with antibiotic antibacterial coatings, non-antibiotic organic antibacterial coatings have a lower risk of resistance (such as chlorhexidine, chloroxylenol, polyhexamethylene biguanide), and can be applied to the body for a relatively longer period. Similarly, non-antibiotic organic antibacterial agent coatings also need to consider suitable coating materials as carriers to meet the drug loading and release methods required in clinical applications.
5. Inorganic antibacterial coating
Inorganic antibacterial coatings have the advantages of strong antibacterial ability, good biocompatibility and stability, and can be widely used in medical devices. Inorganic antibacterial coatings include silver, copper, zinc, chlorine, fluorine, etc. They can be loaded by anodizing or plasma immersion, and rely on the released ions to destroy bacterial cell membranes and inhibit metabolism and antibacterial. Silver is the best known of various inorganic fungicides and has many antibacterial advantages: broad antimicrobial range, low concentrations of silver can inhibit Gram-positive/negative bacilli and some drug-resistant bacteria; silver inhibits bacterial adhesion to The surface of the implant biomaterial does not affect the activity of bone cells and epithelial cells; the antibacterial effect of silver is relatively long-lasting and it is not easy to develop drug resistance; silver as a coating has good biocompatibility, no genetic and cytotoxicity; silver coating The layer is relatively stable and can be prepared by various techniques; silver can be added as an additive to various biological materials to improve its performance; the antibacterial ability of silver can be enhanced by other conditions.
The emergence of biomaterial-related infection cases has made people aware of the importance of antibacterial materials, and promoted the research and development of new antibacterial implants and antibacterial coatings. It can only prevent early postoperative infection due to surgical contamination. The preparation of intraplant coatings with high-loading antibacterial agents and long-term controllable release is one of the research directions of antibacterial coatings in the future, which is of great significance for preventing biomaterial-related infections.
Ultrasonic nozzles are particularly suitable for a wide range of medical coating applications due to their very precise, non-blocking, repeatable spray performance and extremely low flow rate capability. For several years, Cheersonic has been providing ultrasonic medical coating system to medical device manufacturers worldwide. As medical device technology evolves, we will continue to design unique medical coating ultrasonic spray solutions to enhance patient safety and provide the highest quality medical device coating on the market.
