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

Nanophotonic biosensors for point-of-care COVID-19 diagnostics and coronavirus surveillance

The COVID-19 pandemic has revealed the need of novel diagnostic technologies for rapid and accurate virus detection. In the European CONVAT project, a point-of-care nanophotonic biosensor is being developed for the direct, fast and specific identification of severe acute respiratory syndrome coronavirus 2 from both human patient samples and animal reservoirs. The technology will provide a quantitative detection of the viral load and it can be implemented in decentralized settings to improve the early diagnosis and clinical management of patients as well as coronavirus environmental monitoring to prevent future outbreaks

Integrated optical bimodal waveguide biosensors : principles and applications

Altres ajuts: the ICN2 is funded by the CERCA program/Generalitat de Catalunya.Integrated optical biosensors have become one of the most compelling technologies for the achievement of highly sensitive, multianalyte, portable and easy to use point-of-care (POC) devices with tremendous impact in healthcare and environmental protection, among other application fields. In this context, bimodal waveguide (BiMW) interferometers have emerged over the last years as a powerful biosensor technology providing the benefits of extreme sensitivity under a label-free scheme, reliability and robustness within a highly compact footprint that can be integrated and multiplexed in lab-on-a-chip (LOC) platforms. In this review, we provide an overview of the state-of-the-art about integrated optical BiMW biosensors from the theoretical fundamentals to their practical implementation. Furthermore, we explore recent advances such as novel designs, integration in specific LOC systems and its application in real biosensing scenarios. Final remarks and perspectives on the potential impact of these biosensor interferometric structures are also provided, as well as some limitations that must be addressed in next steps

Breakthroughs in photonics 2012: 2012 breakthroughs in lab-on-a-chip and optical biosensors

Open Access.-- Invited Paper.We review the most important achievements published in 2012 in the field of lab-on-a-chip (LOC) and optical biosensors. We will specially focus on optical label-free biosensors and their implementation into lab-on-a-chip platforms, with an emphasis on manuscripts demonstrating bioanalytical applications. © 2009-2012 IEEE.Peer Reviewe

-a-Chip and Optical Biosensors

Abstract: We review the most important achievements published in 2012 in the field of lab-on-a-chip (LOC) and optical biosensors. We will specially focus on optical label-free biosensors and their implementation into lab-on-a-chip platforms, with an emphasis on manuscripts demonstrating bioanalytical applications

Label-free plasmonic biosensors for point-of-care diagnostics : a review

Introduction: Optical biosensors, particularly those based on nanoplasmonics technology, have emerged in recent decades as a potential solution for disease diagnostics and therapy follow-up at the point-of-care (POC). These biosensor platforms could overcome some of the challenges faced in conventional diagnosis techniques offering label-free assays with immediate results and employing small and user-friendly devices. Areas covered: In this review, we will provide a critical overview of the recent advances in the development of nanoplasmonic biosensors for the POC diagnostics. We focus on those systems with demonstrated capabilities for integration in portable platforms, highlighting some of the most relevant diagnostics applications targeting proteins, nucleic acids, and cells as disease biomarkers. Expert commentary: Despite the attractive features of label-free nanoplasmonic sensors in terms of miniaturization and analytical robustness, the route toward an effective clinical implementation involves the integration of fully automated microfluidic systems for sample processing and analysis, and the optimization of surface biofunctionalization procedures. Additionally, the development of multiplexed sensors for high-throughput analysis and including specific neoantigens and novel biomarkers in detection panels will provide the means for delivering a powerful analytical technology for an accurate and improved medical diagnosis

Real time optical immunosensing with flow-through porous alumina membranes

Through the presentation of analytical data from bioassay experiments, measured by polarimetry, we demonstrate for the first time a real time immunoassay within a free standing macroporous alumina membrane. The 200 nm nominal pore diameter of the membrane enables flow-through, thereby providing an ideal fluidic platform for the targeted delivery of analytes to bioreceptors immobilized on the pore walls, enabling fast sensing response times and the use of small sample volumes (<100 μL). For the immunoassay, the pore walls were first coated with the functional copolymer, copoly(DMA-NAS) using a novel coupling process, before immobilization of the allergen protein, β-lactoglobulin, by spotting. The immuno-assay then proceeded with the binding of the primary and secondary antibody cognates, rabbit anti-β-lactoglobulin and anti-rabbit IgG respectively. Through the use of streptavidin coated quantum dots as refractive index signal enhancers, a noise floor for individual measurements of 3.7 ng/mL (25 pM) was obtained, with an overall statistical, or formal assay LOD of 33.7 ng/mL (225 pM), for total assay time below 1 h

Silicon-Based Integrated Label-Free Optofluidic Biosensors: Latest Advances and Roadmap

By virtue of the well-developed micro- and nanofabrication technologies and rapidly progressing surface functionalization strategies, silicon-based devices have been widely recognized as a highly promising platform for the next-generation lab-on-a-chip bioanalytical systems with a great potential for point-of-care medical diagnostics. Herein, an overview of the latest advances in silicon-based integrated optofluidic label-free biosensing technologies relying on the efficient interactions between the evanescent light field at the functionalized surface and specifically bound analytes is presented. State-of-the-art technologies demonstrating label-free evanescent wave-based biomarker detection mainly encompass three device configurations, including on-chip waveguide-based interferometers, microring resonators, and photonic-crystal-based cavities. Moreover, up-to-date strategies for elevating the sensitivities and also simplifying the sensing processes are discussed. Emerging laboratory prototypes with advanced integration and packaging schemes incorporating automatic microfluidic components or on-chip optoelectronic devices lead to one significant step forward in real applications of decentralized diagnostics. Besides, particular attention is paid to currently commercialized label-free optical bioanalytical models on the market. Finally, the prospects are elaborated with several research routes toward chip-scale, low-cost, highly sensitive, multi-functional, and user-friendly bioanalytical systems benefiting to global healthcare. © 2020 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinhei

Trends of biosensing: plasmonics through miniaturization and quantum sensing

Despite being extremely old concepts, plasmonics and surface plasmon resonance-based biosensors have been increasingly popular in the recent two decades due to the growing interest in nanooptics and are now of relevant significance in regards to applications associated with human health. Plasmonics integration into point-of-care devices for health surveillance has enabled significant levels of sensitivity and limit of detection to be achieved and has encouraged the expansion of the fields of study and market niches devoted to the creation of quick and incredibly sensitive label-free detection. The trend reflects in wearable plasmonic sensor development as well as point-of-care applications for widespread applications, demonstrating the potential impact of the new generation of plasmonic biosensors on human well-being through the concepts of personalized medicine and global health. In this context, the aim here is to discuss the potential, limitations, and opportunities for improvement that have arisen as a result of the integration of plasmonics into microsystems and lab-on-chip over the past five years. Recent applications of plasmonic biosensors in microsystems and sensor performance are analyzed. The final analysis focuses on the integration of microfluidics and lab-on-a-chip with quantum plasmonics technology prospecting it as a promising solution for chemical and biological sensing. Here it is underlined how the research in the field of quantum plasmonic sensing for biological applications has flourished over the past decade with the aim to overcome the limits given by quantum fluctuations and noise. The significant advances in nanophotonics, plasmonics and microsystems used to create increasingly effective biosensors would continue to benefit this field if harnessed properly