Colorimetric assay for protein detection based on "nano-pumpkin" induced aggregation of peptide-decorated gold nanoparticles.
Small peptide can be used as an effective biological recognition element and provide an alternative tool for protein detection. However, the development of peptide-based detecting strategy still remains elusive due to the difficulty of signal transduction. Herein, we report a peptide-based colorimetric strategy for the detection of disease biomarker by using vascular endothelial growth factor receptor 1 (Flt-1) as an example. In this strategy, N-terminal aromatic residue-containing peptide modified gold nanoparticles (GNPs) can form bulky aggregate by the introduction of cucurbit[8]uril (CB[8]) that can selectively accommodate two N-terminal aromatic residue of peptides simultaneously regardless of their sequences. However, in the presence of Flt-1, the peptide can specifically bind to the protein molecule and the N-terminal aromatic residue will be occupied, resulting in little aggregation of GNPs. By taking advantage of the highly affinitive peptide and efficiency cross-linking effect of CB[8] to GNPs, colorimetric assay for protein detection can be achieved with a detection limit of 0.2 nM, which is comparable with traditional methods. The feasibility of our method has also been demonstrated in spiked serum sample, indicating potential application in the future.
State Key Laboratory of Pharmaceutical Biotechnology, Department of Biochemistry, Nanjing University, Nanjing 210093, PR China.
Luming
L
Wei
Department of Oncology, the First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, PR China.
Xiaoying
X
Wang
State Key Laboratory of Pharmaceutical Biotechnology, Department of Biochemistry, Nanjing University, Nanjing 210093, PR China.
Chao
C
Li
State Key Laboratory of Pharmaceutical Biotechnology, Department of Biochemistry, Nanjing University, Nanjing 210093, PR China.
Xiaoxi
X
Li
Department of Oncology, the First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, PR China.
Yongmei
Y
Yin
State Key Laboratory of Pharmaceutical Biotechnology, Department of Biochemistry, Nanjing University, Nanjing 210093, PR China; Laboratory of Biosensing Technology, School of Life Sciences, Shanghai University, Shanghai 200444, PR China. Electronic address: genxili@nju.edu.cn.
Genxi
G
Li
D020099:Coated Materials, Biocompatible / Q000737:chemistry; D003124:Colorimetry / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D053761:Nanocomposites / Q000737:chemistry / Q000648:ultrastructure; D010455:Peptides / Q000737:chemistry*; D040081:Protein Array Analysis / Q000295:instrumentation*; D025941:Protein Interaction Mapping / Q000295:instrumentation*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D020099:Coated Materials, Biocompatible; D010455:Peptides; D006046:Gold
Cucurbit[8]Uril; Gold nanoparticle; Peptide; Protein detection