In the medical field, injection molding technology is widely used in manufacturing various medical device components due to its advantages of high efficiency, precision, and large-scale production, such as syringes, infusion sets, catheters, and implant casings. These medical injection-molded parts come into direct or indirect contact with the human body, making their biocompatibility a key factor concerning patient health, treatment efficacy, and the safety of medical devices. The following elaborates in detail on why biocompatibility is of utmost importance for medical injection-molded parts from multiple aspects.

Ensuring Patient Safety

• Avoiding Short-Term Adverse Reactions
  When medical injection-molded parts come into contact with the human body momentarily or in the short term, poor biocompatibility can trigger a series of acute adverse reactions. For example, when using an injection-molded syringe for drug injection, if the syringe material reacts chemically with the drug or human tissue and releases harmful substances, it may cause redness, swelling, pain, and allergies at the injection site. In severe cases, it can even lead to systemic allergic reactions such as rashes, difficulty breathing, and shock, seriously threatening the patient's life. For instance, certain plastic injection-molded parts containing plasticizers may have the plasticizers migrate into drugs or human body fluids, causing toxicity to the human body. On the other hand, injection-molded parts made of materials with good biocompatibility are chemically stable and do not react harmfully with the surrounding environment, effectively preventing these short-term adverse reactions.
• Preventing Long-Term Potential Hazards
  For some medical injection-molded parts that are in long-term contact with the human body or implanted inside the body, such as the plastic components of artificial joints and the casings of pacemakers, biocompatibility is even more critical. If the material has poor biocompatibility, during long-term use, it may continuously release tiny particles or harmful substances, triggering chronic inflammatory reactions in the human body. This chronic inflammation can gradually damage surrounding tissues, affect organ function, and even cause the implant to loosen or fail, necessitating a second surgical replacement. This brings great pain and economic burdens to patients. For example, some early artificial joint materials had suboptimal biocompatibility. After long-term use, wear particles would form around the joints, triggering macrophage reactions and leading to bone resorption and joint loosening. In contrast, modern materials with good biocompatibility can coexist harmoniously with human tissues and reduce long-term potential hazards.

Ensuring Treatment Efficacy

• Maintaining the Stability of Medical Device Performance
  The biocompatibility of medical injection-molded parts directly affects the performance stability of medical devices in actual use. Take infusion sets as an example. If the inner wall material of an infusion set reacts with the infused drug, it may cause the drug to adsorb onto the tube wall, reducing the effective concentration of the drug and affecting the treatment efficacy. At the same time, the biocompatibility of the material also affects the permeability and smoothness of the infusion set. If the material reacts with the drug or blood, precipitates or blockages may form, interfering with the normal infusion process and even endangering the patient's life. In contrast, infusion set injection-molded parts made of materials with good biocompatibility can ensure the accurate infusion of drugs and maintain the performance stability of medical devices, thus ensuring treatment efficacy.
• Promoting Tissue Repair and Regeneration
  In some implantable medical injection-molded parts, such as tissue engineering scaffolds, biocompatibility is the key to promoting tissue repair and regeneration. Tissue engineering scaffolds provide a three-dimensional spatial structure for cell growth and tissue regeneration, and their materials need to have good biocompatibility to support cell adhesion, proliferation, and differentiation. Only in this way can cells grow normally on the scaffold and gradually form new tissues, achieving the repair and regeneration of damaged tissues. If the scaffold material has poor biocompatibility, cells cannot grow well on its surface and may even be poisoned by the harmful substances produced by the material, leading to the failure of tissue repair.

Complying with Regulations and Industry Standards

• Ensuring the Legal Marketing of Medical Devices
  Countries around the world have formulated strict regulations and standards for the biocompatibility of medical devices. In China, the research, development, production, and marketing of medical devices must comply with relevant regulations such as the "Regulations on the Supervision and Administration of Medical Devices," which clearly stipulate that medical devices must have good biocompatibility. Internationally, the International Organization for Standardization (ISO) has also formulated a series of standards for the biocompatibility evaluation of medical devices, such as the ISO 10993 series standards, which provide detailed regulations on the biocompatibility testing methods and evaluation criteria of medical devices. As an important part of medical devices, medical injection-molded parts must meet the requirements of these regulations and standards to obtain approval from regulatory authorities and be legally marketed. Otherwise, they will face serious consequences such as product recalls and fines, and may even affect the company's reputation and survival.
• Enhancing Corporate Competitiveness
  In the highly competitive medical device market, the biocompatibility of products has become an important manifestation of a company's core competitiveness. Medical injection-molded parts with good biocompatibility can provide patients with safer and more effective treatment options and are more likely to gain the recognition and trust of doctors and patients. At the same time, products that comply with regulations and standards can also reduce the risks and costs for companies during the research, development, production, and marketing processes and improve their economic benefits. Therefore, paying attention to the biocompatibility of medical injection-molded parts helps companies improve product quality and market competitiveness and occupy a favorable position in the market.

Reducing Medical Costs

• Cutting Down on Complication Treatment Expenses
  As mentioned earlier, medical injection-molded parts with poor biocompatibility may cause various adverse reactions and complications in patients, requiring additional treatment and care. These additional treatment costs not only bring economic burdens to patients but also increase the overall costs of the healthcare system. In contrast, the use of medical injection-molded parts with good biocompatibility can effectively reduce the incidence of complications, decrease patients' treatment expenses and hospital stays, and thus reduce overall medical costs.
• Extending the Service Life of Medical Devices
  Medical injection-molded parts with good biocompatibility can coexist harmoniously with human tissues, reducing material wear, corrosion, and aging and extending the service life of medical devices. This means that patients do not need to frequently replace medical devices, reducing the procurement and usage costs of medical devices. At the same time, for medical institutions, it can also reduce equipment maintenance and renewal costs and improve the utilization efficiency of medical resources.

In conclusion, biocompatibility is of utmost importance for medical injection-molded parts. It not only relates to patient safety and treatment efficacy but also affects the legal marketing of medical devices, corporate competitiveness, and medical costs. Therefore, during the design, research and development, and production of medical injection-molded parts, great importance must be attached to biocompatibility issues. Appropriate materials should be selected, and strict biocompatibility evaluations and tests should be carried out to ensure the quality and safety of medical injection-molded parts and provide strong guarantees for patient health and the development of the medical industry.