Main types of gold nanoparticle based biosensors are optical and electrochemical biosensor. An aligned carbon nanotube ultrasensitive biosensor for DNA detection was developed. Examples also include development of food quality monitoring sensors and microfluidic biosensor components. Or unique polymers can be used to immobilize enzymes and act in an electrochemical biosensor. A chemical sensor based on recognition material of biological nature is a biosensor. An "in vivo" biosensor is an implantable device that operates inside the body. A cascade nanozyme biosensor was developed for detection of viable Enterobacter sakazakii. An example of an "in vitro" biosensor is an enzyme-conductimetric biosensor for blood glucose monitoring. Most advanced biosensor implants have been developed for the continuous monitoring of glucose. In diagnostic biosensor applications Nanobodies may be used prospectively as a tool. Tissues are used for biosensor for the abundance of enzymes existing. MFCs can measure the solute concentration of wastewater (i.e., as a biosensor). Due to their small size, they can be coupled more densely on biosensor surfaces. Aptamer grafting biosensor is placed on SPRM after rinsing.