PMID- 20394414
OWN - NLM
STAT- MEDLINE
DCOM- 20100818
LR  - 20151119
IS  - 1520-6882 (Electronic)
IS  - 0003-2700 (Linking)
VI  - 82
IP  - 9
DP  - 2010 May 1
TI  - Inhibitory effect of target binding on hairpin aptamer sticky-end pairing-induced 
      gold nanoparticle assembly for light-up colorimetric protein assay.
PG  - 3890-8
LID - 10.1021/ac100422h [doi]
AB  - Gold nanoparticles (GNPs) possessing strong distance-dependent optical properties 
      and high extinction coefficients have emerged as important colorimetric 
      materials. Almost all colorimetric studies are based on two working mechanisms: 
      sandwich cross-linking and non-cross-linking systems. In the present study, a new 
      working mechanism, hairpin sticky-end pairing-induced GNP assembly, is introduced 
      based on the discovery of unique aggregation behavior of aptamer-functionalized 
      GNPs. The salt-induced aggregation of oligonucleotide probe-modified GNPs can 
      readily occur due to the sticky-end pairing effect while addition of target 
      molecules favors the formation of the hairpin structure of probe sequences and 
      substantially inhibits the nanoparticle assembly. Along this line, we developed a 
      proof-of-concept colorimetric homogeneous assay using immunoglobulin E (IgE) as 
      an analyte model via transforming a commonly designed "light-down" colorimetric 
      biosensor into a "light-up" one. From the point of view of both conformational 
      transition of aptamer and steric bulk, oligonucleotide-GNPs display an additional 
      stability upon binding to target molecules. The assay showed an extremely high 
      sensitivity from both naked eye observations and absorbance measurements. 
      Compared with almost all existing IgE sensing strategies, the proposed 
      colorimetric system possesses a substantially improved analytical performance. 
      Investigating the assembly behavior of hairpin aptamer-modified GNPs could offer 
      new insight into the dependence of the GNP properties on the structure switching 
      and open a new way to design signaling probes and develop colorimetric assay 
      schemes.
FAU - Wu, Zai-Sheng
AU  - Wu ZS
AD  - State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry 
      and Chemical Engineering, Hunan University, Changsha, PR China. 
      wuzaisheng@163.com
FAU - Lu, Haixia
AU  - Lu H
FAU - Liu, Xueping
AU  - Liu X
FAU - Hu, Rong
AU  - Hu R
FAU - Zhou, Hui
AU  - Zhou H
FAU - Shen, Guoli
AU  - Shen G
FAU - Yu, Ru-Qin
AU  - Yu RQ
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Anal Chem
JT  - Analytical chemistry
JID - 0370536
RN  - 0 (Aptamers, Nucleotide)
RN  - 0 (Biomarkers)
RN  - 0 (Proteins)
RN  - 7440-57-5 (Gold)
SB  - IM
MH  - Aptamers, Nucleotide/*chemistry
MH  - Biomarkers/analysis/chemistry
MH  - Colorimetry/methods
MH  - Gold/*chemistry
MH  - Light
MH  - Metal Nanoparticles/*chemistry
MH  - Protein Binding
MH  - Proteins/*analysis/chemistry
EDAT- 2010/04/17 06:00
MHDA- 2010/08/19 06:00
CRDT- 2010/04/17 06:00
PHST- 2010/04/17 06:00 [entrez]
PHST- 2010/04/17 06:00 [pubmed]
PHST- 2010/08/19 06:00 [medline]
AID - 10.1021/ac100422h [doi]
PST - ppublish
SO  - Anal Chem. 2010 May 1;82(9):3890-8. doi: 10.1021/ac100422h.