Back to Search
Start Over
Colorimetric Sensing with Gold Nanoparticles on Electrowetting-Based Digital Microfluidics
Colorimetric Sensing with Gold Nanoparticles on Electrowetting-Based Digital Microfluidics
- Source :
- Micromachines, Vol 12, Iss 1423, p 1423 (2021), Micromachines
- Publication Year :
- 2021
- Publisher :
- MDPI AG, 2021.
-
Abstract
- Digital microfluidic (DMF) has been a unique tool for manipulating micro-droplets with high flexibility and accuracy. To extend the application of DMF for automatic and in-site detection, it is promising to introduce colorimetric sensing based on gold nanoparticles (AuNPs), which have advantages including high sensitivity, label-free, biocompatibility, and easy surface modification. However, there is still a lack of studies for investigating the movement and stability of AuNPs for in-site detection on the electrowetting-based digital microfluidics. Herein, to demonstrate the ability of DMF for colorimetric sensing with AuNPs, we investigated the electrowetting property of the AuNPs droplets on the hydrophobic interface of the DMF chip and examined the stability of the AuNPs on DMF as well as the influence of evaporation to the colorimetric sensing. As a result, we found that the electrowetting of AuNPs fits to a modified Young–Lippmann equation, which suggests that a higher voltage is required to actuate AuNPs droplets compared with actuating water droplets. Moreover, the stability of AuNPs was maintained during the processing of electrowetting. We also proved that the evaporation of droplets has a limited influence on the detections that last several minutes. Finally, a model experiment for the detection of Hg2+ was carried out with similar results to the detections in bulk solution. The proposed method can be further extended to a wide range of AuNPs-based detection for label-free, automatic, and low-cost detection of small molecules, biomarkers, and metal ions.
- Subjects :
- Materials science
Biocompatibility
Mechanical Engineering
Metal ions in aqueous solution
Communication
Microfluidics
analytical instrument
Evaporation
Nanotechnology
electrowetting
digital microfluidic
Control and Systems Engineering
Colloidal gold
Electrowetting
TJ1-1570
Surface modification
Digital microfluidics
Mechanical engineering and machinery
Electrical and Electronic Engineering
gold nanoparticle
colorimetric sensing
Subjects
Details
- Language :
- English
- Volume :
- 12
- Issue :
- 1423
- Database :
- OpenAIRE
- Journal :
- Micromachines
- Accession number :
- edsair.doi.dedup.....b0ef51ef5020a03154aaee691e4a69fe