Time-resolved single-step protease activity quantification using nanoplasmonic resonator sensors.
Protease activity measurement has broad application in drug screening, diagnosis and disease staging, and molecular profiling. However, conventional immunopeptidemetric assays (IMPA) exhibit low fluorescence signal-to-noise ratios, preventing reliable measurements at lower concentrations in the clinically important picomolar to nanomolar range. Here, we demonstrated a highly sensitive measurement of protease activity using a nanoplasmonic resonator (NPR). NPRs enhance Raman signals by 6.1 x 10(10) times in a highly reproducible manner, enabling fast detection of proteolytically active prostate-specific antigen (paPSA) activities in real-time, at a sensitivity level of 6 pM (0.2 ng/mL) with a dynamic range of 3 orders of magnitude. Experiments on extracellular fluid (ECF) from the paPSA-positive cells demonstrate specific detection in a complex biofluid background. This method offers a fast, sensitive, accurate, and one-step approach to detect the proteases' activities in very small sample volumes.
Sun
Cheng
C
Nanoscale Science and Engineering Center, University of California, Berkeley, CA 94720, USA. c-sun@northwestern.edu
Su
Kai-Hung
KH
Valentine
Jason
J
Rosa-Bauza
Yazmin T
YT
Ellman
Jonathan A
JA
Elboudwarej
Omeed
O
Mukherjee
Bipasha
B
Craik
Charles S
CS
Shuman
Marc A
MA
Chen
Fanqing Frank
FF
Zhang
Xiang
X
D045744:Cell Line, Tumor; D057075:Enzyme Assays / Q000295:instrumentation* / Q000379:methods; D006801:Humans; D007700:Kinetics; D008297:Male; D036103:Nanotechnology; D017430:Prostate-Specific Antigen / Q000378:metabolism*; D011471:Prostatic Neoplasms / Q000175:diagnosis / Q000201:enzymology; D013997:Time Factors
D017430:Prostate-Specific Antigen