CSpace  > 应用物理研究中心
A competitive colorimetric chloramphenicol assay based on the non-cross-linking deaggregation of gold nanoparticles coated with apolyadenine-modified aptamer
Xie, Yuanyang1,2; Huang, Yu1; Tang, Dongyun1; Cui, Hongliang1; Cao, Haiyan3
2018-12-01
摘要A competitive colorimetric assay has been established to detect chloramphenicol (CAP). It is based on the use of colloidal and electrostatically stabilized aptamer-modified gold nanoparticles (GNPs). The CAP aptamer is modified by a sequence of 5 adenosine groups to anchor it on the surface of GNPs. It can competitively capture two compounds, viz. D-(-)-threo-2-amino-1-(4-nitrophenyl)-1,3-propanediol (CAP-base, with a positive charge) and CAP (which is uncharged). The capture of the positively charged CAP-base triggers the aggregation of modified GNPs in salt-containing solution, and this causes a color change from red to purple. However, in the presence of CAP and CAP-base, the capture of the uncharged CAP weakens this color change by a competing process for capture. Thus, the concentration of CAP is associated with the degree of deaggregation of GNPs and can be quantified by the ratio of absorbances at 620nm and 520nm. The assay has a 22nM limit of detection in acidic solution, and the response is linear in the range of 0.20 to 3.20M CAP concentration. This assay was successfully applied to the determination of CAP in spiked environmental water samples. Conceivably, this method has a wide scope in that it may be applied to a wide range of analytes if respective aptamers are available.
关键词D-(-)-threo-2-amino-1-(4-nitrophenyl)-1,3-propanediol Surface charge Water analysis
DOI10.1007/s00604-018-3067-0
发表期刊MICROCHIMICA ACTA
ISSN0026-3672
卷号185期号:12页码:9
收录类别SCI
WOS记录号WOS:000449518500002
语种英语