ICYS Annual Report 2023

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ICYS Annual Report 2023 Signal outputDetection methodHydrothermalMoX+/DETA, SeCdSNRIrSe2/WSe2@CdS NREDAAntibodyVirusSampleFTO11 The schematic illustration of a ternary IrSe2@WSe2-CdS nanorod photocatalytic system, where core-shelled IrSe2@WSe2 cocatalysts are selectively grown on both ends of CdS nanorods is shown in Fig.1. The modified electrode with IrSe2@WSe2-CdS nanorods is employed for virus detection, with the detection signal primarily reliant on the photocurrent response generated by the novel photo electrocatalyst IrSe2@WSe2-CdS nanorods upon excitation (Fig.1). The proposed architecture of IrSe2@WSe2-CdS effectively the hole and electron regulates recombination rate, thereby enhancing the photo-catalytic performance of the sensor. The IrSe2@WSe2-CdS nanorods (NRs) are synthesized through edge-terminated attachment, where clusters of an IrSe2 core covered with a WSe2 shell preferentially grow on the tips of the CdS NRs, as depicted schematically in Fig. 2a. Initially, amine-functionalized CdS NRs are synthesized via an ethylenediamine (EDA)-assisted solvothermal reaction, yielding CdS NRs with an average diameter of 50 nm (Fig. 2b). High-resolution transmission electron microscopy (HRTEM) confirms the high crystallinity of the CdS NRs, with lattice fringes along the [001] Research Digest Akhilesh Babu GANGANBOINAFig. 2. The (a) schematic illustration of the formation of IrSe2@WSe2-CdS. (b) Typical TEM, (c) HRTEM image and the corresponding FFT pattern of CdS NR, (d) TEM, (e) HAADF-STEM. (f) The photocurrent response of the electrode after incubation with various concentrations of HEV-LPs, (g) calibration curve obtained using change in photocurrent vs. concentration of HEV-LPs in buffer and (h) calibration curve for HEV-LPs using in 10% human serum as a sensing medium.References1) Ganganboina et. al. Biosens. Bioelectron. 185,113261, 2021. 2) Qin et. Al. ACS Nano, 16, 2997-3007, 2022. 3) Ganganboina et. al. Microchemica acta., 190, 46, 2023.1. Outline of ResearchIn the absence of therapeutic agents, early-stage detection of viruses and other pathogens is imperative for outbreak prevention and pandemic control [1]. The prerequisite involves the design of a biosensor capable of yielding a quantitative signal for individual viral or pathogen particles [2]. Self-powered photoelectrochemical (PEC) sensors have emerged as a promising technology in healthcare systems for their potential to achieve ultrasensitive virus detection [3]. In this study, we propose an advanced and upgraded system for ultrasensitive virus detection using a self-powered PEC detection method. One significant aspect that remains relatively unexplored is the precise engineering of core-shell cocatalyst components. To address this, we present a ternary IrSe2@WSe2-CdS nanorod IrSe2@WSe2 photocatalytic system, where core-shelled cocatalysts are selectively grown on both ends of CdS nanorods.2. Research Activities2.1. IrSe2@WSe2-CdS nanorod based PEC system for HEV detection.axis and lattice spacings corresponding to the (002) and (100) planes of CdS (Fig. 2c). The amine-functionalized CdS NRs are further decorated with symmetric core-shelled IrSe2@WSe2 tips (Fig. 2d) in a diethylenetriamine (DETA)/H2O structure with symmetrical tips consisting of an IrSe2 core and a WSe2 shell is confirmed by high-angle annular dark-field (HAADF) scanning transmission electron microscopy and elemental mapping (Fig. 2e). Elemental mapping reveals the specific distribution of elements within the nanocomposites, with Ir, W, and Se concentrating at the tips of the CdS NRs, with Ir at the center, while Cd and S are primarily located in the stem part of the NRs.2.2 Photoelectrochemical Detection The photocurrent response at various concentration range of HEV-LPs continuously increased with the increase in HEV-LPs concentration (Fig. 2f). The linear relationship between the change in photocurrent and the HEV-LPs concentration ranging from 10 fg mL–1 to 10 pg mL–1, shows a correlation coefficient of 0.991 (Fig. 2g). These results indicate that the developed PEC sensor for HEV-LPs detection exhibits benefits, including ultra-sensitivity of the electrochemical method and wide linear range detection, which can offer accurate and reliable quantitative results. To examine the effect of complex matrix we have spiked the diluted serum samples with HEV-LPs and performed detection. Fig. 2h shows the calibration line for HEV-LPs detection using 10% human serum as a detection medium. The responsive linearity of the HEV-LPs detection confirmed the applicability of the developed method in a sophisticated serum matrix.Fig. 1. Schematic Illustration of IrSe2@WSe2-CdS nanorod based PEC system for HEV detection12Dual non-noble-metal Cocatalysts Heterostructure for Virus Detection