Optical Nanosensors and Nanobiosensors
Read full article onlineFull Article
Advances in nanotechnology and nanofabrication have begun to have profound effects on many different scientific fields in recent years. In the field of chemical and biological sensing, one of the most significant advances in the last several decades has been the development of nanosensors, for the probing of microscopic environments. Simply stated, nanosensors are devices with dimensions on the nanometer scale that are capable of monitoring the presence of a specific chemical or class of chemicals. Although many different types of nanosensors (i.e., optical, electrochemical, etc.) have been reported in the literature over the last two decades, this chapter will focus on nanosensors employing optical transduction methods.
As with larger optical sensors, optical nanosensors can generally be classified into one of two different classes: 1) chemical nanosensors, or 2) nanobiosensors, depending on the type of recognition element (i.e., chemical or biochemical) used to provide specificity to the sensor. Although both of these classes of optical nanosensors are capable of obtaining quantitative measurements in many different microscopic environments, they have found an ideal application in the analysis of chemical and biochemical species present within living cells. Their small sizes allow them to be inserted and precisely positioned within individual cells to obtain spatially localized measurements of chemical species in real time.