Chapter 12 Quantum Dot Nanoparticles for In Vitro Sensing

Biological systems are complex entities consisting of various components such as proteins, DNAs, RNAs, lipids and carbohydrates. These building blocks usually have multiple interactions with other components, forming complicated networks to sustain life phenomena. A biosensor is an analytical device that detects the presence and/or function of one or multiple parameters in such a system by adopting biological components. Currently, many research applications focus on the integration of nanotechnology into biosensor design. This chapter will give a short overview of nanoparticles for in vitro biosensing with a focus on semiconductor quantum dots (QDs). We will introduce some important biological targets, define the most important requirements for a biosensor, present some concepts of nanoparticle functionalization and highlight some recent multiplexed approaches concerning QD–gold nanoparticle combination, the application of QDs in charge transfer with ruthenium complexes and the use of chemiluminescence and luminescent lanthanide complexes for FRET to QDs.