Visual and Portable Strategy for Copper(II) Detection Based on a Striplike Poly(Thymine)-Caged and Microwell-Printed Hydrogel

• Published in: Analytical chemistry (Washington) Vol. 86; no. 22; pp. 11263 - 11268
• Main Authors: Qing, Zhihe, Mao, Zhengui, Qing, Taiping, He, Xiaoxiao, Zou, Zhen, He, Dinggeng, Shi, Hui, Huang, Jin, Liu, Jianbo, Wang, Kemin
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 18.11.2014
• Subjects: Analytical chemistry; Copper; Copper - analysis; Fluorescence; Hydrogel, Polyethylene Glycol Dimethacrylate - chemistry; Hydrogels; Nanoparticles; Poly T - chemistry; Portability; Strategy; Symbols; Ultraviolet; Ultraviolet radiation; Visual
• ISSN: 0003-2700; 1520-6882
• DOI: 10.1021/ac502843t

Due to its importance to develop strategies for copper­(II) (Cu2+) detection, we here report a visual and portable strategy for Cu2+ detection based on designing and using a strip-like hydrogel. The hydrogel is functionalized through caging poly­(thymine) as probes, which can effectively template the formation of fluorescent copper nanoparticles (CuNPs) in the presence of the reductant (ascorbate) and Cu2+. On the hydrogel’s surface, uniform wells of microliter volume (microwells) are printed for sample-injection. When the injected sample is stained by Cu2+, fluorescent CuNPs will be in situ templated by poly T in the hydrogel. With ultraviolet (UV) irradiation, the red fluorescence of CuNPs can be observed by naked-eye and recorded by a common camera without complicated instruments. Thus, the strategy integrates sample-injection, reaction and indication with fast signal response, providing an add-and-read manner for visual and portable detection of Cu2+, as well as a strip-like strategy. Detection ability with a detectable minimum concentration of 20 μM and practically applicable properties have been demonstrated, such as resistance to environmental interference and good constancy, indicating that the strategy holds great potential and significance for popular detection of Cu2+, especially in remote regions. We believe that the strip-like hydrogel-based methodology is also applicable to other targets by virtue of altering probes.