Surface plasmon resonance sensor using polypyrrole-chitosan/graphene quantum dots layer for detection of sugar

The Polypyrrole-chitosan/graphene quantum dots nanocomposite layer was prepared by using electrochemical deposition on the surface of gold-coated glass. The prepared layer was used to detect and measure the low concentration of glucose, fructose, and sucrose, using the surface plasmon resonance sensor. X-ray diffraction spectroscopy, and field emission scanning electron microscopy confirmed the GQDs as being formed in the composite layer. The thickness of the polypyrrolechitosan/graphene quantum dots composite layer was in the range of 10.2 nm to 46.5 nm. The sensitivity of the sensor for glucose detection was higher than fructose and sucrose. The sensor limit and the response time were about 1 ppm and 320 s, respectively.