Electroanalytical Paper-Based Nucleic Acid Amplification Biosensors with Integrated Thread Electrodes.
Shirin KhaliliazarAnna ToldràGeorgios ChondrogiannisMahiar Max HamediPublished in: Analytical chemistry (2021)
Nucleic acid amplification tests (NAATs) are very sensitive and specific methods, but they mainly rely on centralized laboratories and therefore are not suitable for point-of-care testing. Here, we present a 3D microfluidic paper-based electrochemical NAAT. These devices use off-the-shelf gold plasma-coated threads to integrate electroanalytical readouts using ex situ self-assembled monolayer formation on the threads prior to assembling into the paper device. They further include a sandwich hybridization assay with sample incubation, rinsing, and detection steps all integrated using movable stacks of filter papers to allow time-sequenced reactions. The devices use glass fiber substrates for storing recombinase polymerase amplification reagents and conducting the isothermal amplification. We used the paper-based device for the detection of the toxic microalgae Ostreopsis cf. ovata. The NAAT, completed in 95 min, attained a limit of detection of 0.06 pM target synthetic DNA and was able to detect 1 ng/μL O. cf. ovata genomic DNA with negligible cross-reactivity from a closely related microalgae species. We think that the integration of thread electrodes within paper-based devices paves the way for digital one-time use NAATs and numerous other advanced electroanalytical paper- or textile-based devices.
Keyphrases
- nucleic acid
- label free
- loop mediated isothermal amplification
- cystic fibrosis
- high throughput
- real time pcr
- gold nanoparticles
- air pollution
- single cell
- wastewater treatment
- reduced graphene oxide
- high resolution
- circulating tumor cells
- mass spectrometry
- risk assessment
- molecularly imprinted
- circulating tumor
- drug induced
- simultaneous determination