An effective chemical modification startegy, integrated in a silicon biosensor, was investigated for the rapid and sensitive electrochemical detection of low amount of pathogen DNA without the amplification PCR step. The miniaturised biosensor was composed by three planar microelectrodes for the electrochemical transduction for the hybridization event with DNA target occurring at the working electrode. The event is proved by an intercalative Os-complex. The core of the proposed detection strategy is based on the immobilization on the working electrode of two oligonucleotide probes, specific for the two DNA semi-elix. The assay here presented was able to detect up to 200 copies of HBV (Hepatites Virus) genome extracted from human blood.
Petralia et al, Analyst 2017, Advanced article DOI:10.1039/C7AN00202e
Petrali et al, Sensing and Biosensing Research 2015, 6, 690-694