A facile assay for direct colorimetric visualization of lipopolysaccharides at low nanomolar level
lipopolysaccharide (LPS), endotoxin, Gram-negative, sensor, gold nanoparticle
ABSTRACT We report a facile assay for the rapid visual detection of lipopolysaccharide (LPS) molecules down to the low nanomolar level by taking advantage of the electrostatic interaction between LPS molecules and cysteaminemodified gold nanoparticles (CSH–Au NPs). The large amount of negatively charged groups on the LPS molecules make LPS highly negatively charged. Thus, when modified with cysteamine, the positively charged gold nanoparticles can aggregate in the presence of trace amounts of LPS. The probe is simple, does not require any advanced instrumentation, and the limit of detection (LOD) was determined to be as low as 3.3 × 10–10 mol/L. To the best of our knowledge, it is the most sensitive synthetic LPS sensor reported so far.
Tsinghua University Press
Jiayu Sun,Jiechao Ge,Weimin Liu,Xueliang Wang,Zhiyuan Fan,Wenwen Zhao,Hongyan Zhang,Pengfei Wang,Shuit-Tong Lee, A facile assay for direct colorimetric visualization of lipopolysaccharides at low nanomolar level. NanoRes.2012, 5(7): 486–493