They present a novel, sensitive Cu2+ sensor based on the use of dynamic light scattering (DLS) to detect difference in the hydrodynamic diameter of gold nanoparticles (AuNPs). The ability of DNA to adsorb on the AuNPs changes with the presence of Cu2+, affecting the disperse state of the AuNPs and, therefore, their average hydrodynamic diameter.
The Cu2+ ion plays a key role in many metabolic processes, so being able to accurately determine levels of Cu2+ is important in various aspects of biology.
The authors applied their technique to water samples and say that it is both simple and timesaving, with the potential to be extended to other bioassays in the future.
A highly sensitive sensor for Cu2+ with unmodified gold nanoparticles and DNAzyme by using the dynamic light scattering technique
Xiangmin Miao, Liansheng Ling, Du Cheng and Xintao Shuai
Analyst, 2012, Advance Article
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