Molecular PINCERs(®) are antibody-based protein sensors that allow rapid and sensitive detection of specific proteins in solution. The sensors allow quick detection of a target, with sensitivity and specificity approaching that of conventional immunoassays, but require no sample manipulation other than mixing of the test sample with sensors. Combining the PINCER assay with immunoprecipitation allows quick and sensitive detection of anti-HCV immunoglobulin (Ig)G and IgM in human serum. This improvement is achieved through binding of anti-HCV IgG and IgM from serum to HCV-antigen-immobilized microspheres, followed by quantification of the IgG and IgM using molecular PINCERs. The PINCER-based assay is cost-effective, sensitive and has potential for clinical diagnostic use.