Department of Chemistry, Faculty of Science, Srinakharinwirot University, Sukhumvit 23, Wattana, Bangkok 10110, Thailand.
Electrochemistry and Optical Spectroscopy Centre of Excellence (EOSCE), Department of Chemistry, Faculty of Science, Chulalongkorn University, Patumwan, Bangkok 10330, Thailand.
Int J Mol Sci. 2019 Jun 17;20(12):2954. doi: 10.3390/ijms20122954.
A simple and novel transparency sheet-based colorimetric detection device using gold nanoparticles (AuNPs) modified by 4-Amino-6-hydroxy-2-mercaptopyrimidine monohydrate (AHMP) was fabricated and developed for the determination of calcium ions (Ca). The detection was based on a colorimetric reaction as a result of the aggregation of modified AuNPs induced by Ca due to the ability to form strong electrostatic interactions between positively charged Ca and negatively charged modified AuNPs. Probe solution changes color from red to blue in the presence of Ca and can be observed by the naked eyes. To verify the complete self-assembly of the AHMP onto the AuNP surface, the modified AuNPs were characterized using ultraviolet-visible spectroscopy and zeta potential measurements. Under optimal conditions, a quantitative linearity was 10 to 100 ppm ( = 0.9877) with a detection limit of 3.05 ppm. The results obtained by the developed method were in good agreement with standard atomic absorption spectrometry (AAS) results and demonstrated that this method could reliably measure Ca. Overall, this novel alternative approach presents a low-cost, simple, sensitive, rapid, and promising device for the detection of Ca.
一种基于透明胶片的新型比色检测装置，使用 4-氨基-6-羟基-2-巯基嘧啶单水合物（AHMP）修饰的金纳米粒子（AuNPs），被开发用于钙离子（Ca）的测定。检测基于比色反应，由于带正电荷的 Ca 和带负电荷的修饰 AuNPs 之间能够形成强静电相互作用，导致修饰的 AuNPs 因 Ca 的存在而聚集。在 Ca 的存在下，探针溶液从红色变为蓝色，肉眼可观察到。为了验证 AHMP 完全自组装到 AuNP 表面，使用紫外-可见光谱和zeta 电位测量对修饰的 AuNPs 进行了表征。在最佳条件下，定量线性范围为 10 至 100ppm（=0.9877），检测限为 3.05ppm。该方法得到的结果与标准原子吸收光谱法（AAS）结果一致，表明该方法能够可靠地测量 Ca。总的来说，这种新颖的替代方法为 Ca 的检测提供了一种低成本、简单、灵敏、快速和有前景的装置。
