Artificial receptors in serologic tests for the early diagnosis of dengue virus infection

Because of the range and nonspecificity of clinical presentations of dengue virus infections, we felt there was a need to create diagnostic tests. We used artificial receptors for the virus to develop serologic assays to detect dengue virus infection.

We coated a quartz crystal microbalance (QCM) with molecularly imprinted polymers specific for nonstructural protein 1 of flavivirus. These artificial receptors were specifically created on a QCM chip by polymerization of monomers and were cross-linked in the presence of the epitope site of nonstructural protein 1. We tested serum samples from patients with confirmed cases of dengue reported to the Center for Disease Control in Taipei. Samples were diluted 100-fold; no other sample pretreatment was used. The QCM response was compared with results of monoclonal ELISA.

QCM signals were >15 Hz in 18 of 21 (86%) of dengue samples and in 0 of 16 control samples. The correlation (r2) of the QCM response and the ELISA result was 0.73. Within-run and run-to-run imprecisions (CV) were 4%-28% and 10%-32%, respectively.

The described assay offers a serologic technique for diagnosis of early viremia. The results illustrate the potential of well-organized polymers on the highly sensitive sensor system for diagnostic and biotechnological applications.