Biointerfaces Institute , McMaster University , 1280 Main Street West , Hamilton , ON L8S 4O3 , Canada.
Anal Chem. 2019 Apr 2;91(7):4735-4740. doi: 10.1021/acs.analchem.9b00235. Epub 2019 Mar 14.
A paper based litmus test has been developed using modulation of urease enzyme activity for detection of C-C mismatch single nucleotide polymorphisms (SNPs) by the naked eye. Urease is first inactivated with silver ions and printed onto paper microzones. Addition of DNA containing C-C mismatches reactivates urease via binding of Ag(I), allowing restoration of urease activity, hydrolysis of urea to produce ammonia, and an increase in pH, which is monitored colorimetrically using a pH indicator with a limit of detection of 11 nM DNA in 40 min. The assay system is easy to use, portable, and stable for at least 30 days at ambient temperature. To assess the versatility and practical application of the paper sensor, we used it to identify a G > C transversion present in human genomic DNA from a ductal carcinoma cell line, a mutation commonly found in breast cancer. We believe this new assay system has the potential to be a low-cost method for rapidly identifying DNA with the C-C mismatch SNP as a means of cancer screening in resource-limited areas.
一种基于纸张的石蕊测试已被开发出来，该测试利用脲酶酶活性的调节，通过肉眼检测 C-C 错配单核苷酸多态性 (SNP)。首先用银离子使脲酶失活，并将其打印到纸张微区上。添加含有 C-C 错配的 DNA 通过与 Ag(I)结合使脲酶重新激活，从而恢复脲酶活性，将尿素水解产生氨，并使 pH 值升高，这可以使用 pH 指示剂通过比色法进行监测，检测限为 40 分钟内 11 nM DNA。该测定系统易于使用，便携，在环境温度下至少稳定 30 天。为了评估纸张传感器的多功能性和实际应用，我们将其用于鉴定来自导管癌细胞系的人类基因组 DNA 中存在的 G > C 颠换，这是一种在乳腺癌中常见的突变。我们相信，这种新的测定系统有可能成为一种低成本方法，用于快速识别具有 C-C 错配 SNP 的 DNA，作为资源有限地区癌症筛查的一种手段。
