Silicon photonic chip-based biosensor for COVID-19 and flu detection with high sensitivity and specificity

Since the end of 2021, Omicron, the new variant of SARS-CoV-2, has continued to spread as the predominant strain of COVID-19. Compared to previous variants, Omicron causes milder symptoms, which are similar to symptoms of other common respiratory infections, such as flu. In this work, we develop a silicon photonic chip-based biosensor for COVID-19 and flu detection using subwavelength grating micro-ring resonator. The biosensor realizes the detection of two pathogens with high sensitivity (1.31 fg/mL) and specificity. Besides, the microfluidic channel offers a promising solution for point-of-care detection. © 2023 SPIE.

Solid-Phase Optical Sensing Techniques for Sensitive Virus Detection.

Viral infections can pose a major threat to public health by causing serious illness, leading to pandemics, and burdening healthcare systems. The global spread of such infections causes disruptions to every aspect of life including business, education, and social life. Fast and accurate diagnosis of viral infections has significant implications for saving lives, preventing the spread of the diseases, and minimizing social and economic damages. Polymerase chain reaction (PCR)-based techniques are commonly used to detect viruses in the clinic. However, PCR has several drawbacks, as highlighted during the recent COVID-19 pandemic, such as long processing times and the requirement for sophisticated laboratory instruments. Therefore, there is an urgent need for fast and accurate techniques for virus detection. For this purpose, a variety of biosensor systems are being developed to provide rapid, sensitive, and high-throughput viral diagnostic platforms, enabling quick diagnosis and efficient control of the virus's spread. Optical devices, in particular, are of great interest due to their advantages such as high sensitivity and direct readout. The current review discusses solid-phase optical sensing techniques for virus detection, including fluorescence-based sensors, surface plasmon resonance (SPR), surface-enhanced Raman scattering (SERS), optical resonators, and interferometry-based platforms. Then, we focus on an interferometric biosensor developed by our group, the single-particle interferometric reflectance imaging sensor (SP-IRIS), which has the capability to visualize single nanoparticles, to demonstrate its application for digital virus detection.

On-chip multivariant COVID 19 photonic sensor based on silicon nitride double-microring resonators

Coronavirus disease 2019 (COVID-19) is a newly emerging human infectious disease that continues to develop new variants. A crucial step in the quest to reduce the infection is the development of rapid and reliable virus detectors. Here, we report a chip scale photonic sensing device consisting of a silicon-nitride double microring resonator (MRR) for detecting SARS-CoV-2 in clinical samples. The sensor is implemented by surface activation of one of the MRRs, acting as a probe, with DNA primers for SARS-CoV-2 RNA, whereas the other MRR is used as a reference. The performance of the sensor is determined by applying different amounts of SARS-CoV-2 complementary RNA. As will be shown in the paper, our device detects the RNA fragments at concentrations of 10 cp/μL and with sensitivity of 750 nm/RIU. As such, it shows a promise toward the implementation of label-free, small form factor, CMOS compatible biosensor for SARS-CoV-2, which is also environment, temperature, and pressure independent. Our approach can also be used for detecting other SARS-CoV-2 genes, as well as other viruses and pathogens. © 2023 the author(s), published by De Gruyter, Berlin/Boston 2023.

Automated sample-to-answer system for rapid and accurate diagnosis of emerging infectious diseases

Automated sample-to-answer systems that promptly diagnose emerging infectious diseases, such as zoonotic diseases, are crucial to preventing the spread of infectious diseases and future global pandemics. However, automated, rapid, and sensitive diagnostic testing without professionals and sample capacity and type limitations remains unmet needs. Here, we developed an automated sample-to-answer diagnostic system for rapid and accurate detection of emerging infectious diseases from clinical specimens. This integrated system consists of a microfluidic platform for sample preparation and a bio-optical sensor for nucleic acid (NA) amplification/detection. The microfluidic platform concentrates pathogens and NAs in a large sample volume using adipic acid dihydrazide and a low-cost disposable chip. The bio-optical sensor allows label-free, isothermal one-step NA amplification/detection using a ball-lensed optical fiber-based silicon micro-ring resonator sensor. The system is integrated with software to automate testing and perform analysis rapidly and simply;it can distinguish infection status within 80 min. The detection limit of the system (0.96 × 101 PFU) is 10 times more sensitive than conventional methods (0.96 × 102 PFU). Furthermore, we validated the clinical utility of this automated system in various clinical specimens from emerging infectious diseases, including 20 plasma samples for Q fever and 13 (11 nasopharyngeal swabs and 2 saliva) samples for COVID-19. The system showed 100% sensitivity and specificity for detecting 33 samples of emerging infectious diseases, such as Q fever, other febrile diseases, COVID-19, human coronavirus OC43, influenza A, and respiratory syncytial virus A. Therefore, we envision that this automated sample-to-answer diagnostic system will show high potential for diagnosing emerging infectious diseases in various clinical applications. © 2023 Elsevier B.V.

Detection of SARS-CoV-2 Nucleocapsid Protein Using Si Microring Resonator Biosensor

In this study, a fabricated silicon (Si) microring resonator biosensor was able to detect 500 fg/mL of the SARS-CoV-2 nucleocapsid protein in phosphate-buffered saline. The relationship between the amount of wavelength shift and refractive index change is investigated in this work. © 2022 IEICE.

A Point-of-care Biosensor with Subwavelength Grating Waveguide-based Micro-ring Resonator for Detection of COVID-19

We present an on-chip optical biosensor for the detection of COVID-19. The subwavelength grating waveguide-based micro-ring resonator with high sensitivity and low limit of detection integrates with microfludic channel, which promises clinical utility in point-of-care diagnostic. © Optica Publishing Group 2022, © 2022 The Author(s)

SARS-CoV-2 PROTEINS AND BIOTOXIN DETECTION USING PHOTONIC RESONATOR SENSOR

The great advances in silicon photonic-sensing technology have made it an attractive platform for wide sensing applications. The small size of chip and detection system makes photonic microring resonator can be used in clinic for quick detection of disease. Here, we employ the high sensitivity of the photonic sensor toward the change of refractive index for the detection of SARS-CoV-2 virus spike proteins and botulinum toxin in water. The system require very small amount of sample 50uL with high sensitivity, in short 1hr without pre-treatment required. The measurement can be automatic with minimum manpower involved. Moreover, the system can be multiplexed to detect a few target analytes at the same time in one sample. © 2021 MicroTAS 2021 - 25th International Conference on Miniaturized Systems for Chemistry and Life Sciences. All rights reserved.

Strategies for the development of photonic sensors for COVID-19

Beyond the optical and analytical performance of the sensor itself, the development of an optical detection tool in response to a pressing research or diagnostic need requires consideration of a host of additional factors. This talk will provide an overview of two photonic sensor systems developed for profiling the human immune response to COVID-19 infection and/or vaccination. One, focused on the design goal of high multiplexing (many targets per sensor), was built on the Arrayed Imaging Reflectometry (AIR) platform. AIR is a free-space optics technique that relies on the creation and target molecule binding-induced disruption of an antireflective coating on the surface of a silicon chip. The second method, focused on low cost and high speed, uses a small (1 x 4 mm) ring resonator photonic chip embedded in a plastic card able to provide passive transport of human samples. This “disposable photonics” platform is able to detect and quantify anti-COVID antibodies in a human sample in a minute, making it attractive for high-throughput testing applications. © 2022 SPIE

Rotationally Symmetric Nanowire Array-based Virus Detection: Single or Multiple Arrays?

In this work we compare the prospect of detecting virus-like particles using single and multiple arrays of rotationally symmetric array of silicon nanowires. Taking the dimension and geometry of the Coronavirus as a reference, resonant wavelength shift and quality factor change of the whispering gallery mode of the nanowire array in the presence of one and two viruses are evaluated employing finite difference time domain analysis technique. For a single coronavirus having protein spike, the maximum shift of resonant wavelength is found to be about 5 nm, whereas for two viruses the shift can be as high as 9 nm. However, interestingly, for two viruses the shift appear to change periodically depending on relative location of the virus particles. As far as multiple arrays for virus detection is concerned, the quality factor of the most strongly confined whispering gallery mode appears to have been reduced by 50% or more because of mode-leakage resulting from coupling between the nanowire arrays. Such weaker confinement of the optical field though may have a diminishing effect on the signal to noise ratio during practical measurements, the detection sensitivity appears to have improved significantly because of the sustenance of whispering gallery resonant modes in the adjacent nanowire arrays. © 2021 IEEE.

Al2O3referenced microring resonators for the detection of interleukin-6

Concentrations down to 300 pM of the interleukin-6 biomarker, identified as an inflammatory marker for severe COVID-19 infection, have been detected in buffer using referenced microring resonators in the emerging Al2O3 integrated photonic platform. Antifouling was achieved by applying an Xantec HC1000M hydrogel. © 2021 IEEE.