Wireless Lateral Flow Device for Biosensing

Abstract

Many biosensing methods rely on signals produced by enzyme-catalyzed reactions and efficient methods to detect and record this activity. Herein, we report a wireless lateral flow device and demonstrate the conversion of oxidase reactions to changes in the resonance of radio frequency identification (RFID) circuits. The detection is triggered by polyoxometalate-catalyzed oxidative doping of polypyrrole (pPy) when exposed to oxidase-generated H2O2. We have integrated this transduction and RFID capability into a lateral flow device to create a low-cost, rapid, and portable method for quantitative biological signal detection. We further report a new method for creating functional coatings from pPy core–shell colloidal particles bioconjugated for streptavidin–biotin recognition with glucose oxidase or pyruvate oxidase. The biofunctionalized pPy particles coalesce on the nitrocellulose membrane to produce a chemiresistive band. Glucose or pyruvate solutions result in formation of H2O2 at the pPy bands, functionalized with the respective oxidase, to produce conductivity enhancements exceeding 7·105%. Placing the pPy band in the RFID circuit converts the resistivity response to a change of RF resonance. The enzymatic response of glucose oxidase is recorded within 30 min with as low as 0.6 mM of glucose using this lateral flow device. Pyruvate is also shown to produce large responses. The oxidase enzymes/pPy transduction establishes a resistivity-based platform for the construction of a new family of lateral flow devices capable of detecting and quantifying biological targets.

Water-soluble conjugated polymers for bioelectronic systems

“…144 More importantly, they integrated the carboxylate-functionalized PPy core–shell nanoparticles (PPyNPs) with the radio frequency identification (RFID) circuits to create a portable, low-cost and rapid bioelectronic device. 145 The electrical conductivity of carboxylate-functionalized PPyNPs (Fig. 12A) could decrease when exposed to oxidase-generated H 2 O 2 .…”

Cyclodextrin-Functionalized Polypyrrole Particles for the Extraction of Aromatics from Water

“…The polypyrrole shell allows for further functionalization of the particle surfaces, via a reductive conjugate addition to the deprotonated form of doped polypyrrole, 6,7 which we have found has broad utility in tailoring the properties of polypyrrole for specific applications. 8 We hypothesized that functionalization would enhance the extractive capabilities of our particles by the incorporation of supramolecular hosts, such as β-cyclodextrin (β-CD), 9,10 which are well known to interact with aromatic compounds via their hydrophobic cavities. 11,12 Herein, we present our results on the formation of pPy colloidal particles containing β-cyclodextrin and the use of these materials for the extraction of various aromatic compounds from water.…”

“…In our previous studies, we found that these particles can be loaded with various organic dyes, suggesting their potential for extracting organic molecules from solution. The polypyrrole shell allows for further functionalization of the particle surfaces, via a reductive conjugate addition to the deprotonated form of doped polypyrrole, , which we have found has broad utility in tailoring the properties of polypyrrole for specific applications . We hypothesized that functionalization would enhance the extractive capabilities of our particles by the incorporation of supramolecular hosts, such as β-cyclodextrin (β-CD), , which are well known to interact with aromatic compounds via their hydrophobic cavities. , …”

Integrated SERS-Vertical Flow Biosensor Enabling Multiplexed Quantitative Profiling of Serological Exosomal Proteins in Patients for Accurate Breast Cancer Subtyping

“…A majority of studies have combined SERS with the paper-based lateral flow assay (LFA) – the most widely used point-of-care (POC) diagnostic format that could clinically analyze free proteins or exosomal proteins in complex matrices such as saliva, urine, whole blood. − In the LFA biosensors, the capillary forces drive the lateral flow of the clinical liquid samples containing analytes along the surface of the nitrocellulose (NC) membrane. The main merits of LFA include low cost, fast result readout, simplicity, and ease-to-use; however, one major hurdle of the LFA platform is the limited multiplexing capability due to its in-line design geometry. , A few LFA biosensors have been reported for multiplexed detection of proteins, but they usually suffer from cross-reactivity and false-negative results due to the hook effect, and measure at most two protein biomarkers. − These inherent drawbacks compromise the diagnostic accuracy of LFA. Therefore, there is an urgent need to develop alternative high-throughput POC strategies enabling quantitative detection of a panel of exosomal proteins for cancer liquid biopsies.…”

“…The main merits of LFA include low cost, fast result readout, simplicity, and ease-touse; however, one major hurdle of the LFA platform is the limited multiplexing capability due to its in-line design geometry. 40,41 A few LFA biosensors have been reported for multiplexed detection of proteins, but they usually suffer from cross-reactivity and false-negative results due to the hook effect, and measure at most two protein biomarkers. 42−45 These inherent drawbacks compromise the diagnostic accuracy of LFA.…”