How Nanophotonic Label-Free Biosensors Can Contribute to Rapid and Massive Diagnostics of Respiratory Virus Infections : COVID-19 Case

Altres ajuts: Generalitat de Catalunya /CERCAThis ACS article is provided to You under the terms of this Standard ACS AuthorChoice License. License: https://pubs.acs.org/page/policy/authorchoice_termsofuse.htmlThe global sanitary crisis caused by the emergence of the respiratory virus SARS-CoV-2 and the COVID-19 outbreak has revealed the urgent need for rapid, accurate, and affordable diagnostic tests to broadly and massively monitor the population in order to properly manage and control the spread of the pandemic. Current diagnostic techniques essentially rely on polymerase chain reaction (PCR) tests, which provide the required sensitivity and specificity. However, its relatively long time-to-result, including sample transport to a specialized laboratory, delays massive detection. Rapid lateral flow tests (both antigen and serological tests) are a remarkable alternative for rapid point-of-care diagnostics, but they exhibit critical limitations as they do not always achieve the required sensitivity for reliable diagnostics and surveillance. Next-generation diagnostic tools capable of overcoming all the above limitations are in demand, and optical biosensors are an excellent option to surpass such critical issues. Label-free nanophotonic biosensors offer high sensitivity and operational robustness with an enormous potential for integration in compact autonomous devices to be delivered out-of-the-lab at the point-of-care (POC). Taking the current COVID-19 pandemic as a critical case scenario, we provide an overview of the diagnostic techniques for respiratory viruses and analyze how nanophotonic biosensors can contribute to improving such diagnostics. We review the ongoing published work using this biosensor technology for intact virus detection, nucleic acid detection or serological tests, and the key factors for bringing nanophotonic POC biosensors to accurate and effective COVID-19 diagnosis on the short term

Novel sensing algorithm for linear read-out of bimodal waveguide interferometric biosensors

Altres ajuts: the ICN2 was supported by the CERCA programme of the Generalitat de Catalunya.Biosensors employing photonics integrated circuits, and specifically those that rely on interferometric evanescent wave working principles, have outstanding performances due to the extreme sensitivity exhibited in one-step and direct assay, without the need of amplification. Within the interferometric configurations, the Bimodal Waveguide (BiMW) interferometric sensor stands out due to its demonstrated sensitivity for real-life applications and the simplicity of its design. To overcome the ambiguities that arise from the periodic nature of interferometric read-outs, a new all-optical modulation and the subsequent trigonometry-based algorithm have been proposed and applied to the BiMW biosensor. This new algorithm has been successfully employed for the selective identification and quantification of the external Spike (S) protein of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Our biosensing results from this simple, quick, and user-friendly method demonstrate high sensitivity and specificity and pave the way towards a point-of-care device for general use

Development of the Silicon Photonic Microring Resonator Platform with Applications for the Detection of Nucleic Acids and Other Biopolymers

Progress in the development of biosensors has dramatically improved analytical techniques. Biosensors have advantages over more conventional analytical techniques arising from attributes such as straightforward analyses, higher throughput, miniaturization, smaller sample input, and lower cost. Specifically, silicon-based biosensors including microring resonators have led to major advances in diverse applications because they produce sensors that can be arrayed in planar substrates for multiplexed detection and can be produced at large scales. This dissertation presents how microring resonators have been used for the detection of ribonucleic acids, RNA, and other inorganic biopolymers. The first chapter describes the basics of biosensors and the factors that affect their operation. This chapter is also dedicated to the sensing mechanism of whispering gallery mode biosensors, in the form of microring resonators. In addition, it summarizes the most recent applications of microrings in environmental and clinical analysis, highlighting the research in RNA detection. The next two chapters describes an approach for RNA detection utilizing the microring resonators. This methodology is based on the coupling of a nucleic acid amplification technique, asymmetric Polymer Chain Reaction, aPCR, with the microring resonator platform. Promising results are shown in the detection and quantification of RNA, where our approach offers the sensitivity and selectivity required for the use of transcripts in clinical analysis. Compared to other biosensing strategies, we are able to perform a higher multiplexity of the measurements, use nanogram sample input, and adapt the protocol to the detection of short (microRNAs) and long transcripts (long non-coding RNAs). The fourth chapter presents how the aPCR-microring combination can be applied to the profiling of a miRNA biomarker panel. The investigation consists of an analysis of the dynamic miRNA signatures of two glioblastoma cell lines upon various treatments. Furthermore, I utilized the normalized expression of the miRNAs to construct heatmaps and performed multivariate statistical analysis. The results indicated that this technology makes it possible to carry out functional screening of targets for diagnostic and therapeutic evaluation. The fifth chapter features an innovative application of microrings in the quantitative analysis of polyphosphate, also known as polyP. PolyP is a ubiquitous molecule, interest in which has increased over the last decade because of the discovery of its important biological roles in mammals and microorganisms. However, methodologies for its analysis still fall short in identifying ways to quantifying polyP directly in complex matrices. To detect polyP in complex matrices, molecules are captured in the surface via high-affinity binding to cationic polymers. Then, we integrated a selective recognition of the molecules via a polyphosphate binding protein domain. This strategy enabled the detection of nanomolar concentrations and the measurement of the molecule directly in the matrix with no purification and thus, it opens up a variety of potential applications. The final chapter summarizes all the research carried out during my thesis. The possibilities that microring resonators have to offer as biosensors, and the diverse approaches that can be combined to enhance the characterization of molecules. In the field of RNA, future directions will include the combination of RNA expression panels with the profiling of other biomarkers to understand better the signatures of patient samples under therapeutic treatments. In the field of polyP, future directions in the analysis of polyP are the size characterization of these polymers using other separation instruments such as capillary electrophoresis (CE).PHDChemistryUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttps://deepblue.lib.umich.edu/bitstream/2027.42/151753/1/cardenom_1.pd

How Nanophotonic Label-Free Biosensors Can Contribute to Rapid and Massive Diagnostics of Respiratory Virus Infections : COVID-19 Case

Altres ajuts: Generalitat de Catalunya /CERCAThis ACS article is provided to You under the terms of this Standard ACS AuthorChoice License. License: https://pubs.acs.org/page/policy/authorchoice_termsofuse.htmlThe global sanitary crisis caused by the emergence of the respiratory virus SARS-CoV-2 and the COVID-19 outbreak has revealed the urgent need for rapid, accurate, and affordable diagnostic tests to broadly and massively monitor the population in order to properly manage and control the spread of the pandemic. Current diagnostic techniques essentially rely on polymerase chain reaction (PCR) tests, which provide the required sensitivity and specificity. However, its relatively long time-to-result, including sample transport to a specialized laboratory, delays massive detection. Rapid lateral flow tests (both antigen and serological tests) are a remarkable alternative for rapid point-of-care diagnostics, but they exhibit critical limitations as they do not always achieve the required sensitivity for reliable diagnostics and surveillance. Next-generation diagnostic tools capable of overcoming all the above limitations are in demand, and optical biosensors are an excellent option to surpass such critical issues. Label-free nanophotonic biosensors offer high sensitivity and operational robustness with an enormous potential for integration in compact autonomous devices to be delivered out-of-the-lab at the point-of-care (POC). Taking the current COVID-19 pandemic as a critical case scenario, we provide an overview of the diagnostic techniques for respiratory viruses and analyze how nanophotonic biosensors can contribute to improving such diagnostics. We review the ongoing published work using this biosensor technology for intact virus detection, nucleic acid detection or serological tests, and the key factors for bringing nanophotonic POC biosensors to accurate and effective COVID-19 diagnosis on the short term