Single Molecule Detection in Life Sciences

Abstract

In recent years, the development of single molecule detection (SMD) techniques has opened up a new era of life science. The dynamic properties of biomolecules and the unique operations of molecular machines, which were hidden in averaged ensemble measurements, have been unveiled. The SMD techniques have rapidly been expanding to include a wide range of life science. The experiments on molecular motors, DNA transcription, enzyme reactions, protein dynamics, and cell signaling are summarized in this short review.

Single chain spectroscopy of conformational dependence of conjugated polymer photophysics

“…For example, measurements of inter-and intramolecular binding forces and elastic moduli of biological macromolecules by magnetic beads (2,3), atomic force microscopy (4), hydrodynamic flow (5), or optical tweezers (6) have provided significant insight to the mechanical properties of DNA and proteins. Single molecule fluorescence detection has seen particular interest, because the fluorescence labeling of DNA, RNA, enzymes, and proteins allows for dynamic studies of macromolecular interactions and function, such as complexation (7). The optical visualization of these molecules, however, requires specific labeling with fluorescent dyes or the use of intercalating dyes.…”

A new optical method for characterizing single molecule interactions based on dark field microscopy

“…In the past twenty years, new techniques have been developed that allow the study of single molecules or single molecular events resulting in information on molecular mechanisms 5,6 . Optical and magnetic tweezers, for example, cannot only be used for the detection of single molecules but also for manipulating them and for the determination of associated forces.…”

“…Optical and magnetic tweezers, for example, cannot only be used for the detection of single molecules but also for manipulating them and for the determination of associated forces. Both methods have been extensively used in the characterization of motor proteins, like kinesin and myosin 6 . There are single molecule methods that are based on fluorescence such as fluorescence resonance energy transfer (FRET) and fluorescence correlation spectroscopy (FCS).…”

Advances in the development of a novel method to be used in proteomics using gold nanobeads

“…This does not always permit the understanding of individual molecular mechanisms. In the last ten to twenty years, single-molecule techniques (SMT) 7,8 have become more advanced and new techniques have been developed. These techniques permit the study of molecular mechanisms in a number of different measurements at the single molecule level.…”

“…These techniques permit the study of molecular mechanisms in a number of different measurements at the single molecule level. Molecular motors 8 like kinesin and myosin have been studied by means of optical tweezers, magnetic tweezers and total internal reflection fluorescence microscopy (TIRFM). Other methods that are used in biomechanical studies are scanning probe microscopy (SPM), microneedle, near-field scanning optical microscopy (NSOM), fluorescence resonance energy transfer (FRET), fluorescence correlation spectroscopy (FCS), surface enhanced Raman spectroscopy (SERS), and tethered bead motion (TPM) also called single particle tracking (SPT).…”