Silicon nanowire biosensor for highly sensitive and rapid detection of Dengue virus

The paper presents an innovative silicon nanowire (SiNW)-based sensor for highly sensitive and rapid detection of reverse-transcription-polymerase chain reaction (RT-PCR) product of Dengue serotype 2 (DEN-2). A specific peptide nucleic acid (PNA) was covalently attached onto the SiNW surface. A complementary fragment of DEN-2 (69 bp) was obtained through one-step RT-PCR amplification, and applied to the PNA-functionalized SiNW. The hybridization event was verified by measuring the resistance change of the SiNW before and after binding of the RT-PCR product of DEN-2 to the PNA sequence. It is found that the SiNW sensor can detect below 10 fM concentration of the amplicons within 30 min. The approach shows potential of eliminating the demand for laborious methods by integrating the SiNW sensor with RT-PCR based on silicon technology platform. Consequently, this system-scale integration for a point-of-care medical device will facilitate the diagnostic applications.