An Enzyme-Free Signal Amplification Technique for Ultrasensitive Colorimetric Assay of Disease Biomarkers
Enzyme-based colorimetric assays have been widely used in research labs and clinical diagnosis for decades. Nevertheless, as constrained by the performance of enzymes, their detection sensitivity has not been substantially improved in recent years, which inhibits many critical applications such as early detection of cancers. In this work, we demonstrate an enzyme-free signal amplification technique, based on gold vesicles encapsulated with Pd-Ir nanoparticles as peroxidase mimics, for colorimetric assay of disease biomarkers with significantly enhanced sensitivity. This technique overcomes the intrinsic limitations of enzymes, thanks to the superior catalytic efficiency of peroxidase mimics and the efficient loading and release of these mimics. Using human prostate surface antigen as a model biomarker, we demonstrated that the enzyme-free assay could reach a limit of detection at the femtogram/mL level, which is over 10 3-fold lower than that of conventional enzyme-based assay when the same antibodies and similar procedure were used.
- Authors:
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[1]
; [2]
; [3]
; [2]
; [2]
; [4]
;
[2]
; [1]
- Michigan Technological Univ., Houghton, MI (United States). Dept. of Chemistry
- Univ. of Maryland, College Park, MD (United States). Dept. of Chemistry and Biochemistry
- Brookhaven National Lab. (BNL), Upton, NY (United States). Condensed Matter Physics and Materials Science Dept.
- Brookhaven National Lab. (BNL), Upton, NY (United States). Condensed Matter Physics and Materials Science Dept.; Michigan Technological Univ., Houghton, MI (United States). Dept. of Chemical Engineering
- Publication Date:
- Report Number(s):
- BNL-113910-2017-JA
Journal ID: ISSN 1936-0851; R&D Project: MA015MACA; KC0201010
- Grant/Contract Number:
- SC0012704
- Type:
- Accepted Manuscript
- Journal Name:
- ACS Nano
- Additional Journal Information:
- Journal Volume: 11; Journal Issue: 2; Journal ID: ISSN 1936-0851
- Publisher:
- American Chemical Society (ACS)
- Research Org:
- Brookhaven National Laboratory (BNL), Upton, NY (United States)
- Sponsoring Org:
- USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 59 BASIC BIOLOGICAL SCIENCES; 60 APPLIED LIFE SCIENCES; biomarker; detection; enzyme mimic; gold vesicle; iridium nanoparticles
- OSTI Identifier:
- 1372434
- Free Publicly Accessible Full Text
-
Accepted Manuscript (DOE)
- Publisher's Version of Record
- https://doi.org/10.1021/acsnano.6b08232