Multiplex DNA sensor for BRAF and BRCA detection

In this article, a kind of simple, sensitive, and rapid quantum dots (QDs)-based multiplex DNA sensor is developed for the simultaneous detection of BRAF and BRCA DNA based on the nano-on-micro technique. In our strategy, capture DNA(BRCA) and DNA(BRAF) are simultaneously immobilized on the surface of amino-modified silica microbeads. After blocking with bovine serum albumin (BSA), different concentrations of target DNA(BRCA) and DNA(BRAF) are introduced to hybrid with complementary capture DNA(BRCA) and DNA(BRAF). After hybridization, QDs(546)-labeled probe DNA(BRAF) and QDs(657)-labeled probe DNA(BRCA) were added into the above solution so that the unreacted capture DNA(BRCA) and DNA(BRAF) could be detected by QDs(657)-labeled probe DNA(BRCA) and QDs(545)-labeled probe DNA(BRAF) simultaneously. We demonstrate that the proposed method is effective for detecting BRAF and BRCA DNA with high sensitivity. The sensor has great potential to expand its application to the early diagnosis of cancers such as breast cancer, ovarian cancer, and papillary thyroid carcinoma. (C) 2013 Elsevier Inc. All rights reserved.