Peptide-based electrochemical approach for apoptosis evaluation.

This paper reports a strategy to assemble apoptotic cells on a solid surface using a peptide as the recognition element. And a peptide-based electrochemical biosensor to directly evaluate apoptosis is described for the first time. The peptide modified on an electrode is designed to contain the sequence that can recognize externalized phosphatidylserine on apoptotic cells, and can then capture the cells onto the electrode surface. In the electrochemical system, the immobilized cells can not only provide significant steric hindrance for electron transfer, but also shield the positive charges of the peptide that can attract negatively charged electrochemical probes. Therefore, the obtained electrochemical signals drop significantly after the incubation of apoptotic cells, which can be used to reveal the apoptosis level. The experimental results of this approach are well in line with other standard methods. Moreover, this electrochemical method is simple, cost-effective, convenient, sensitive, and holds great potential toward apoptosis evaluation, therapeutic effect assessment and deeper cellular biological studies.