3D interior hotspots embedded with viral lysates for rapid and label-free identification of infectious diseases
Soo Hyun Lee, Iris Baffour Ansah, Won‐Chul Lee, Jun-Young Yang, ChaeWon Mun, Hyowon Jang, Sun‐Joo Kim, Sunghoon Jung, Min Young Lee, Ho Sang Jung, Taejoon Kang, Seunghun Lee, Dong‐Ho Kim, Sung‐Gyu Park
Abstract
In recent decades, biomedical sensors based on surface-enhanced Raman spectroscopy (SERS), which reveals unique spectral features corresponding to individual molecular vibrational states, have attracted intensive attention. However, the lack of a system for precisely guiding biomolecules to active hotspot regions has impeded the broad application of SERS techniques. Herein, we demonstrate the irreversible active engineering of three-dimensional (3D) interior organo-hotspots via electrochemical (EC) deposition onto metal nanodimple (ECOMD) platforms with viral lysates. This approach enables organic seed-programmable Au growth and the spontaneous bottom-up formation of 3D interior organo-hotspots simultaneously. Because of the net charge effect on the participation rate of viral lysates, the number of interior organo-hotspots in the ECOMDs increases with increasingly positive polarity. The viral lysates embedded in the ECOMDs function as both a dielectric medium for field confinement and an analyte, enabling the highly specific and sensitive detection of SARS-CoV-2 lysates (SLs) at concentrations as low as 10 –2 plaque forming unit/mL. The ECOMD platform was used to trace and detect the SLs in human saliva and diagnose of the delta-type SARS-CoV-2 in clinical environments; the results indicate that the proposed platform can provide point-of-care diagnoses of infectious diseases.