Quantum dots: Emerging trends toward biosensing

Quantum dots (QDs) are tiny nanocrystals of semiconducting elements of groups II–VI, III–IV, and IV. QDs have unique optical properties, notably greater absorption coefficients, emission of light, and higher signal brightness, resulting in the growth of polymer encapsulated probes incorporated with fluorescence properties under biological conditions. During recent years, CQDs and GQDs have been developed with diverse surface morphologies and properties for improved analytical and sensing performance, which brings these materials nearer to practical application. Carbon dots are zero-dimensional carbon nanoparticles of less than 10nm size with inter-planar lattice spacing around 0.34nm for the planes (100) and (002) of graphite. Graphene is a two-dimensional material of sp² hybridized carbon atoms, which has excellent opto-electronic, thermal, and mechanical properties. Us of GQDs makes advanced technology of energy storage possible, due to good chemical reactivity and migration, which allows easy assembling.