Long-term stability and improved reusability of a piezoelectric immunosensor for human erythrocytes

Abstract

The long-term stability and reusability of a recently developed piezoelectric immunosensor for the detection of purified human erythrocytes and erythrocytes in whole human blood was studied. Using polyethyleneimine-anti-glycophorin A antibody-coated gold electrodes a long-term stability of 10 weeks was found when stored dry at room temperature. Storage of 4°C did not improve this stability. To improve the reusability a synthetic peptide corresponding to the human glycophorin A sequence of the amino acids 27–39 was used for competition with the bound antigen. With this technique the number of regeneration could be increased from five to twelve without a decrease in activity.