Advanced in vitro microfluidic tissue models, deemed “tissue chips” or “organs-on-chips”, seek to replicate the complexity of living organisms in a low-cost format suitable for high-throughput experimentation. To date, most such systems have relied on destructive techniques such as immunofluorescence microscopy, or downstream analysis of fluid in the microfluidic path, to report on the activity of the tissue chip under study. In order to provide real-time monitoring capability for tissue chips, we initiated a program to integrate photonic sensors (ring resonators fabricated in silicon nitride) in close proximity to the tissue under study. To date we have succeeded in developing a microfluidic device containing both a nanoporous membrane chip for suspended cell culture, along with a multiplex, antibody-functionalized ring resonator-based photonic sensor chip.
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.
Detection of antibodies to upper respiratory pathogens is critical to surveillance, assessment of the immune status of individuals, vaccine development, and basic biology. The urgent need for antibody detection tools has proven particularly acute in the COVID-19 era. Array-based tools are desirable as methods for assessing broader patterns of antigen-specific responses, as well as providing information on SARS-CoV-2 immunity in the context of pre-existing immunity to other viruses. Also, methods that rapidly and quantitatively detect antibody responses to SARS-CoV-2 antigens using small (fingerstick) quantities of blood are essential for monitoring immunity at a global scale. This talk will describe the development of two optical sensor platforms (Arrayed Imaging Reflectometry, and an integrated photonics platform fabricated at AIM Photonics) for quantifying antibodies to SARS-CoV-2 and other upper respiratory pathogens, and oriented towards the needs of multiplex detection and speed.
Ring resonators fabricated in silicon or silicon nitride constitute one of the most versatile and widely studied platform photonic technologies for biosensing. As part of an effort by AIM Photonics to advance the photonics manufacturing infrastructure of the United States, we have designed, fabricated, and tested a series of silicon nitride ring resonators for biosensing. Optimized designs will be incorporated into the AIM Photonics photonic design kit (PDK) and made available to the broader community. This talk will describe the evolution of our designs and their performance, with a particular focus on the detection of cytokines under microfluidic flow.
An effective response to human biowarfare agent exposure events requires the availability of simple, sensitive, reliable, and manufacturable sensing and diagnostic tools. While ring resonators fabricated on a silicon-on-insulator platform have found wide application as enabling components for biosensors, and have even been commercialized successfully, silicon nitride-based ring resonators have received less attention. We hypothesized that silicon nitride would provide both manufacturing and performance advantages over silicon in a biosensing context. To test that hypothesis, we designed a series of silicon nitride ring resonators. Designs were fabricated at the American Institute for Manufacturing Integrated Photonics (AIM Photonics) foundry. We will discuss the design process, optical performance of the manufactured devices, and their use in the label-free detection of biomedically relevant protein targets.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.