title: Ultrasensitive and ultrawide range detection of a cardiac biomarker on a surface plasmon resonance platform.
abstract: One of the main challenges in the development of new analytical platforms for ultrasensitive bioaffinity detection is jointly achieving a wide dynamic range in target analyte concentration, especially for approaches that rely on multistep processes as a part of the signal amplification mechanism. In this paper, a new surface-based sandwich assay is introduced for the direct detection of B-type natriuretic peptide (BNP), an important biomarker for cardiac failure, at concentrations ranging from 1 aM to 500 nM. This was achieved using nanoparticle-enhanced surface plasmon resonance (SPR) where a DNA aptamer is immobilized on a chemically modified gold surface in conjunction with the specific adsorption of antiBNP coated gold nanocubes in the presence of the biomarker target. A concentration detection range greater than eleven orders of magnitude was achieved through dynamic control of only the secondary nanoparticle probe concentration. Furthermore, detection at low attomolar concentrations was also achieved in undiluted human serum.
authors: Department of Chemistry and Green-Nano Materials Research Center, Kyungpook National University , 1370 Sankyuk-dong, Buk-gu, Daegu-city, 702-701, Republic of Korea.
authors: Hye Ri
authors: HR
authors: Jang
authors: Alastair W
authors: AW
authors: Wark
authors: Seung Hee
authors: SH
authors: Baek
authors: Bong Hyun
authors: BH
authors: Chung
authors: Hye Jin
authors: HJ
authors: Lee
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry*; D015415:Biomarkers / Q000032:analysis / Q000097:blood; D006046:Gold / Q000737:chemistry; D006333:Heart Failure / Q000097:blood* / Q000175:diagnosis; D006801:Humans; D008297:Male; D053768:Metal Nanoparticles / Q000737:chemistry*; D020097:Natriuretic Peptide, Brain / Q000032:analysis / Q000097:blood*; D020349:Surface Plasmon Resonance / Q000379:methods* / Q000592:standards*
chemical_list: D052157:Aptamers, Nucleotide; D015415:Biomarkers; D020097:Natriuretic Peptide, Brain; D006046:Gold