Label-free biosensors in the field of stem cell biology.

A great body of evidence unveiled the existence of different stem cell types in various tissues with efficient capability for self-renewal and differentiation. Characterization and enumeration of a specific stem cell population seem difficult because these cells consist of a small percentage of cells within different milieu. As such, due to lack of accuracy provided by convenient methods, biosensing techniques are at the center of attention to improve stem cells characterization with high rate of sensitivity and specificity. In line with this statement, bio-sensing, as a sensitive analytical method, opens novel avenues in biological aspects. Physicochemical signals produced by the interaction of analyte-ligands could be applicable for a wide range of scientific fields such as chemical, biochemical, pharmaceutical and immunological purposes. Noninvasive and label free monitoring methods without need to stain, fix, lyse, or fluorescent-tags are desirable in basic stem cell technology and therapeutic applications of cells. We, here, highlighted basic concepts and terms associated with label free biosensor technology for measuring cell entity, evaluating cell surface marker, and peculiarly in the field of stem cell biology. Furthermore, different aspects and methodologies concerning with bio-sensing techniques, including photonic-based detection systems like Surface Plasmon Resonance (SPR) assays, Impedance-based method, Quartz Crystal Microbalance (QCM) and paper based detection of lateral flow biosensor (LFB) were discussed.