TY - JOUR
T1 - Convenient formation of nanoparticle aggregates on microfluidic chips for highly sensitive SERS detection of biomolecules
AU - Zhou, Jianhua
AU - REN, Kangning
AU - Zhao, Yihua
AU - Dai, Wen
AU - Wu, Hongkai
N1 - Funding Information:
Acknowledgments We are grateful to Prof. Xiaoyuan Li (Department of Chemistry, The Hong Kong University of Science and Technology, Hong Kong) for allowing us to use their Raman instruments. This work was supported by the Hong Kong RGC (#605210).
PY - 2012/2
Y1 - 2012/2
N2 - Microfluidic chips combined with surface-enhanced Raman spectroscopy (SERS) offer an outstanding platform for rapid and high-sensitivity chemical analysis. However, it is nontrivial to conveniently form nanoparticle aggregrates (as SERS-active spots for SERS detection) in microchannels in a well-controlled manner. Here, we present a rapid, highly sensitive and label-free analytical technique for determining bovine serum albumin (BSA) on a poly(dimethylsiloxane) (PDMS) microfluidic chip using SERS. A modified PDMS pneumatic valve and nanopost arrays at the bottom of the fluidic microchannel are used for reversibly trapping gold nanoparticles to form gold aggregates, creating SERS-active spots for Raman detection. We fabricated a chip that consisted of a T-shaped fluidic channel and two modified pneumatic valves, which was suitable for fast loading of samples. Quantitative analysis of BSA is demonstrated with the measured peak intensity at 1,615 cm -1 in the surface-enhanced Raman spectra. With our microfluidic chip, the detection limit of Raman can reach as low as the picomolar level, comparable to that of normal mass spectrometry.
AB - Microfluidic chips combined with surface-enhanced Raman spectroscopy (SERS) offer an outstanding platform for rapid and high-sensitivity chemical analysis. However, it is nontrivial to conveniently form nanoparticle aggregrates (as SERS-active spots for SERS detection) in microchannels in a well-controlled manner. Here, we present a rapid, highly sensitive and label-free analytical technique for determining bovine serum albumin (BSA) on a poly(dimethylsiloxane) (PDMS) microfluidic chip using SERS. A modified PDMS pneumatic valve and nanopost arrays at the bottom of the fluidic microchannel are used for reversibly trapping gold nanoparticles to form gold aggregates, creating SERS-active spots for Raman detection. We fabricated a chip that consisted of a T-shaped fluidic channel and two modified pneumatic valves, which was suitable for fast loading of samples. Quantitative analysis of BSA is demonstrated with the measured peak intensity at 1,615 cm -1 in the surface-enhanced Raman spectra. With our microfluidic chip, the detection limit of Raman can reach as low as the picomolar level, comparable to that of normal mass spectrometry.
KW - Aggregates
KW - Gold nanoparticles
KW - Highly sensitive detection
KW - Microfluidics
KW - Surface-enhanced Raman spectroscopy
UR - http://www.scopus.com/inward/record.url?scp=84856216826&partnerID=8YFLogxK
U2 - 10.1007/s00216-011-5585-z
DO - 10.1007/s00216-011-5585-z
M3 - Journal article
C2 - 22127578
AN - SCOPUS:84856216826
SN - 1618-2642
VL - 402
SP - 1601
EP - 1609
JO - Analytical and Bioanalytical Chemistry
JF - Analytical and Bioanalytical Chemistry
IS - 4
ER -