Conjugates of streptavidin with gold nanoparticles for the visualization of dna single interactions on the silicon surface
The potential of the method of scanning electron microscopy (SEM) to visualize the results
 of individual acts of DNA and oligonucleotides hybridization using gold nanoparticles as label
 was investigated. Molecule of biotin was introduced into DNA or oligonucleotide, and then it was detected
 in DNA duplex using a conjugate of streptavidin with gold nanoparticles. Effective imaging of DNA duplexes
 was possible using a conjugate prepared by covalent binding.. The detection limit of the model oligonucleotide
 of 19 bases was 20 pg.