Novel Nanocomposite Coatings for Bioresorbable Medical Implants

生物可吸收植入物在心血管支架和骨科等应用中比永久性植入物具有显著优势。它们被设计成一旦它们发挥了临时的结构支撑作用就在体内自然降解，并提供恢复正常组织功能的潜力。然而，一些常用的生物可吸收植入物的降解速度太快，需要新的技术来控制这一速度，从而使组织在生物吸收之前愈合。本项目的目的和目标：1）开发一种由生物相容性聚合物和纳米石墨烯材料组成的新型纳米复合涂层，以控制生物可吸收植入物的降解情况2）探索复合涂层的多功能性，包括药物递送和按需光热治疗，这有助于提高治疗效果。方法学：将通过旋涂或浸涂方法将由不同聚合物/纳米石墨烯比例组成的涂层应用于植入物材料。将研究纳米石墨烯浓度和涂层厚度对所得复合涂层性质和功能性的影响。更具体地说，扫描电子显微镜将用于分析涂层微观结构。将进行差示扫描量热法和热重分析来研究涂层材料的热性能。将使用紫外-可见分光光度计测定涂层载药量/释放曲线。采用红外摄像机测量涂层的光热转换效率。植入物的降解可以通过重量测量结合微型计算机断层扫描来确定。在使用生物可吸收金属植入物的情况下，将使用电阻抗光谱法来确定涂层的腐蚀抑制特性。最后，将使用细胞试验研究涂层的生物相容性。该项目与EPSRC医疗保健技术主题战略及其相关的重大挑战密切相关，即“物理干预前沿”，“优化治疗”和“转变社区卫生和护理”。该项目的成功将为设计和制造新型、低成本、多功能的下一代生物医学设备提供关键知识和技术，提高治疗效率，改善患者健康状况。

Bioresorbable implants offer significant advantages over permanent implants in applications such as cardiovascular stents and orthopaedics. They are designed to naturally degrade in the body once they have served their temporary structural support role, and offer the potential for restoration of normal tissue function. However, the degradation rate of some commonly used bioresorbable implants is too fast and new technologies are required to control this rate and therefore allow tissue healing prior to bioresorption.Aim and objectives of this project:1)To develop a novel nanocomposite coating consisting of a biocompatible polymer and nanosized graphene materials to control the degradation profile of the bioresorbable implants2)To explore the multi-functionality of the composite coating, including drug delivery and on-demand photothermal therapy, which can help to enhance the treatment efficacy. Methodology: Coating consisting of different polymer/nanographene ratio will be applied to the implant material via spin coating or dip coating method. The effects of nanographene concentration and the coating thickness on the resulting composite coating properties and functionality will be investigated. More specifically, scannining electron microscopy will be used to analyse the coating microstructure. Differential scanning calorimetry and thermogravimetric analysis will be carried out to investigate the coating material thermal properties. UV-Vis spectrometer will be used to determine the coating drug loading/release profile. Infrared camera will be used to measure the coating photothermal conversion efficiency. The degradation of the implant can be determined by weight measurements in combination with micro computed tomography. In the case where bioresorbable metal implants are used, electro-impedance spectroscopy will be used to determine the coating corrosion inhibition properties. Finally, the biocompatibility of the coating will be studied using cell tests. This project is closely in line with the EPSRC healthcare technologies theme strategy and its associated grand challenges , namely " Frontiers of Physical Intervention", "Optimising Treatment" and "Transforming Community Health and Care". The success of the project will provide key knowledge and technology for the design and fabrication of novel, low-cost, multi-functional next generation biomedical devices with improved treatment efficiency and enhanced patient health outcome.