A Quartz Crystal Microbalance Immunosensor for Stem Cell Selection and Extraction

A cost-effective immunosensor for the detection and isolation of dental pulp stemcells (DPSCs) based on a quartz crystal microbalance (QCM) has been developed. The recognition mechanism relies on anti-CD34 antibodies, DPSC-specificmonoclonal antibodies that are anchored on the surface of the quartz crystals. Due to its high specificity, real time detection, and low cost, the proposed technology has a promising potential in the field of cell biology, for the simultaneous detection and sorting of stem cells from heterogeneous cell samples. The QCMsurface was properly tailored through a biotinylated self-assembled monolayer (SAM). The biotin–avidin interaction was used to immobilize the biotinylated anti-CD34 antibody on the gold-coated quartz crystal. After antibody immobilization, a cellular pellet, with amixed cell population, was analyzed; the results indicated that the developed QCMimmunosensor is highly specific, being able to detect and sort only CD34+ cells. Our study suggests that the proposed technology can detect and efficiently sort any kind of cell fromsampleswith high complexity, being simple, selective, and providing for more convenient and time-saving operations.