Implantable and Semi-Implantable Biosensors for Minimally Invasive Disease Diagnosis

Implantable and semi-implantable biosensors fabricated with biodegradable materials and nanomaterials have gained interest in the past few decades. Functionalized biodegradable materials and nanomaterials are usually employed to satisfy clinical and research requirements because of their advanced properties. Novel fabrication techniques were developed to improve the efficiency and accuracy. Different working mechanisms were facilitated to design different types of sensors. This review discusses the recent developments of implantable and semi-implantable biosensors. The materials and fabrications are browsed, and different types of biomedical sensors for different variables are discussed as a focused topic. The biomedical sensors are discussed according to the targets and working mechanisms, followed by a focus on the nervous system sensing to provide an inspiration that different variables can be studied simultaneously on the single system. In the end, challenges and prospects will be discussed. This review aims to provide information of materials, fabrication approaches, mechanisms, and the state of the art for inspiration in designing novel implantable and semi-implantable biomedical sensors for general diagnostic activities.