Droplet-based microscale colorimetric biosensor for multiplexed DNA analysis via a graphene nanoprobe.
The development of simple and inexpensive DNA detection strategy is very significant for droplet-based microfluidic system. Here, a droplet-based biosensor for multiplexed DNA analysis is developed with a common imaging device by using fluorescence-based colorimetric method and a graphene nanoprobe. With the aid of droplet manipulation technique, droplet size adjustment, droplet fusion and droplet trap are realized accurately and precisely. Due to the high quenching efficiency of graphene oxide (GO), in the absence of target DNAs, the droplet containing two single-stranded DNA probes and GO shows dark color, in which the DNA probes are labeled carboxy fluorescein (FAM) and 6-carboxy-X-rhodamine (ROX), respectively. The droplet changes from dark to bright color when the DNA probes form double helix with the specific target DNAs leading to the dyes far away from GO. This colorimetric droplet biosensor exhibits a quantitative capability for simultaneous detection of two different target DNAs with the detection limits of 9.46 and 9.67×10(-8)M, respectively. It is also demonstrated that this biosensor platform can become a promising detection tool in high throughput applications with low consumption of reagents. Moreover, the incorporation of graphene nanoprobe and droplet technique can drive the biosensor field one more step to some extent.
Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, PR China.
Xia
X
Xiang
Ming
M
Luo
Liyang
L
Shi
Xinghu
X
Ji
Zhike
Z
He
D015374:Biosensing Techniques / Q000295:instrumentation*; D003124:Colorimetry / Q000295:instrumentation*; D004247:DNA / Q000032:analysis*; D015342:DNA Probes / Q000737:chemistry; D004277:DNA, Single-Stranded / Q000737:chemistry; D004867:Equipment Design; D005456:Fluorescent Dyes / Q000032:analysis; D006108:Graphite / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry; D012680:Sensitivity and Specificity
D015342:DNA Probes; D004277:DNA, Single-Stranded; D005456:Fluorescent Dyes; D010087:Oxides; D006108:Graphite; D004247:DNA