earticle

영어

Due to the inter-particle-coupling effect on the surface plasmon resonance of gold nanoparticles (AuNPs), controlled aggregation of AuNPs has been a subject of increasing interest especially for colorimetric detections of biologically or medically important substances. In addition, AuNPs exhibit high efficacy for fluorescence quenching over a wide range of wavelengths than organic molecules because of the strong absorbance extinction and unique dimension. Therefore, AuNPs have been also adapted in fluorescence-change-based monitoring systems. Versatile interactions of nucleic acids with various molecules such as proteins, enzymes, metal ions and chemical compounds and advents of selection technologies for synthetic oligonucleotides called aptamers, DNAzymes, and RNAzymes have spanned the possibility of nucleic acids as biological components with high specificity and affinity in biosensors. In addition, the significant advances for the detection of nucleic acids up to single copy of the target nucleic acids have allowed the nucleic acids as signal amplifying mediators for detections of the non nucleic acid targets. In recent, we developed variety of biosensors combining the functional nucleic acids with AuNPs for detections of medically and environmentally concerned substances including protease, antimicrobial agents, heavy metal ions, and genotoxic drugs. In this talk, we will present the high performances of the biosensors which showed high sensitivity, specificity and also operational feasibility. For examples, DNA mediated amplification of fluorescence signal on AuNPs resulted in 100-fold enhancement of sensitivity for the detection of protease and lead ion and controlled interaction between AuNPs allowed high throughput detection of genotoxic substances including even ultraviolet light in an instrument-free way. We will discuss more details of the working principles and methods to integrate the functional nucleic acids in the nanoparticles based biosensors along with the experimental results.