Year 2022 
Journal Info. Chemical Engineering Journal, 446, 137085 (2022) 
Author Sohyun Park, Chang Su Jeon, Namhyun Choi, Joung-Il Moon, Kang Min Lee, Sung Hyun Pyun*, Taejoon Kang*, and Jaebum Choo* 


Surface-enhanced Raman scattering (SERS)-based assays have been recently developed to overcome the low detection sensitivity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). SERS-based assays using magnetic beads in microtubes slightly improved the limit of detection (LoD) for SARS-CoV-2. However, the sensitivity and reproducibility of the method are still insufficient for reliable SARS-CoV-2 detection. In this study, we developed a SERS-based microdroplet sensor to dramatically improve the LoD and reproducibility of SARS-CoV-2 detection. Raman signals were measured for SERS nanotags in 140 droplets passing through a laser focal volume fixed at the center of the channel for 15 s. A comparison of the Raman signals of SERS nanotags measured in a microtube with those measured for multiple droplets in the microfluidic channel revealed that the LoD and coefficient of variation significantly improved from 36 to 0.22 PFU/mL and 21.2% to 1.79%, respectively. This improvement resulted from the ensemble average effects because the signals were measured for SERS nanotags in multiple droplets. Moreover, the total assay time decreased from 30 to 10 min. A clinical test was performed on patient samples to evaluate the clinical efficacy of the SERS-based microdroplet sensor. The assay results agreed well with those measured by the reverse transcription-polymerase chain reaction (RT-PCR) method. The proposed SERS-based microdroplet sensor is expected to be used as a new point-of-care diagnostic platform for quick and accurate detection of SARS-CoV-2 in the field.

Year Title Journal Info. etc.
2022  Rapid and sensitive detection of lysophosphatidylcholine using Zwitterionic polydiacetylene liposome vesicles and a microfluidic gradient sensor Sensors & Actuators B, in press.   
2022  Dual-mode SERS-based lateral flow assay strips for simultaneous diagnosis of SARS-CoV-2 and influenza A virus Nano Convergence, in press.   
2022  Sensitive and reproducible detection of SARS-CoV-2 using SERS-based microdroplet sensor file Chemical Engineering Journal, 446, 137085 (2022)   
2022  A novel polymer-based nitrocellulose platform for implementing multiplexed microfluidic paper-based enzyme-linked immunosorbent assay file Microsystems & Nanoengineering, 8, 53 (2022)   
2022  Raman thermometry nanopipettes in cancer photothermal therapy file Analytical Chemistry, 94, 6463-6472 (2022)   
2022  Fluorescent probes for biomolecule detection under environmental stress file Journal of Hazardous Materials, 431, 128527 (2022)   
2022  Early and direct detection of bacterial signaling molecules through one-pot Au electrodeposition onto paper-based 3D SERS substrates file Sensors & Actuators B, 358, 131504 (2022)   
2022  iSERS Bioassays In “World Scientific Reference on Plasmonic Nanomaterials :
Principles, Design and Bio-applications. Vol. 5: Plasmonics in Diagnostics
and Therapy” Book Chapter 7, pp 239-265, World Scientific (2022) 
Book Chapter 
2022  Surface-Enhanced Raman Scattering-based Immunoassay for Severe Acute Respiratory Syndrome Coronavirus 2 file Biosensors & Bioelectronics, 202, 114008 (2022)   
2022  SERS-based dual-mode DNA aptasensors for rapid classification of SARS-CoV-2 and influenza A/H1N1 infection file Sensors & Actuators B, 355, 131324 (2022)   
2022  SERS-PCR Assays of SARS-CoV-2 target genes using Au nanoparticles-internalized Au nanodimple substrates file Biosensors & Bioelectronics, 197, 113736 (2022)   
2022  SERS-based microfluidic devices for in vitro diagnostics In "Principles and Clinical Diagnostic Applications of Surface-Enhanced
Raman Spectroscopy" Book Chapter 7, pp 281-302, Elsevier (2022) 
Book Chapter 
2021  Development of SERS-based immunoassay platforms using hollow Au nanostars for reliable SARS-CoV-2 diagnosis file Bull. Kor. Chem. Soc., 42, 1699-1705 (2021)   
2021  Reproducible and sensitive plasmonic sensing platforms based on Au-nanoparticle-internalized nanodimpled substrate file Advanced Functional Materials, 31, 2105703 (2021)  Cover page 
2021  SERS-based serodiagnosis of acute febrile diseases using plasmonic nanopopcorn microarray platforms file Biosensors & Bioelectronics, 192, 113525 (2021)   
2021  Coumarin–lipoic acid conjugates on silver nanoparticle-supported nanopipettes for in situ dual-mode monitoring of intracellular Cu(II) and potential chemodynamic therapy applications file Sensors & Actuators B, 344, 130271 (2021)   
2021  SERS-based test strips: Principles, designs and applications file Biosensors & Bioelectronics, 189, 113360 (2021)   
2021  Sensitive detection of SARS-CoV-2 using SERS-based aptasensor file ACS Sensors, 6, 2378-2385 (2021)   
2021  SERS-based Dual-flow Lateral Flow Assay Sensor for the Ultrasensitive Detection of Thyroid-Stimulating Hormone file Analytical Chemistry, 93, 6673-6681 (2021)   
2021  Molecular Imprinting: Green Perspectives and Strategies file Advanced Materials, 33, 2100543 (2021)