ABSTRACT
One interesting feature of optical frequency comb (OFC) is a function of frequency conversion between region and electric regions. While such feature has been used for generation of correct electric signal in microwave or millimeter region, it can be further used for fiber biosensing;namely, biosensing OFC. In this paper, we demonstrated detection of SARS-CoV-2 antigen based on a combination of dual fiber combs, an intracavity multi-mode-interference fiber sensor, and sensor surface modification of SARS-CoV-2 antibody. © COPYRIGHT SPIE. Downloading of the is permitted for personal use only.
ABSTRACT
Two years into the COVID-19 pandemic and more than one year after the approval of the first vaccine, bottlenecks in production and supply chain infrastructure continue to delay vaccination campaigns in the Global South. Mobile on Demand (MOD) vaccine manufacture may help quickly ramp up production capacity while bypassing infrastructure bottlenecks. Such decentralized small-scale factories can help tip the scales in the battle against COVID-19 and future pandemics. In this work, we designed two MOD vaccine manufacturing units based on a protein antigen expressed in yeast and in vitro transcription of mRNA. Each unit consists of three shipping containers and can produce on the order of 10,000 vaccine doses daily for competitive prices and in close proximity of their end users. Abandoning economies of scale may lead to a moderate increase in production costs that may be outweighed by reduced closed-vial dose wastage and an earlier protection of vulnerable populations. © 2022 American Chemical Society.
ABSTRACT
We demonstrated rapid detection of SARS-CoV-2 nucleocapsid protein antigen by dual-comb biosensing with surface modification of its corresponding antibody. A sensitivity close to that of RT-PCR was achieved, thanks to the use of active-dummy temperature compensation. © Optica Publishing Group 2022, © 2022 The Author(s)
ABSTRACT
To detect and prevent emerging epidemics, discovery platforms are urgently needed, for the rapid development of diagnostic assays. Molecular diagnostic tests for COVID-19 were developed shortly after the isolation of SARS-CoV-2. However, serological tests based on antiviral antibody detection, revealing previous exposure to the virus, required longer testing phases, due to the need to obtain correctly folded and glycosylated antigens. The delay between the identification of a new virus and the development of reliable serodiagnostic tools limits our readiness to tackle future epidemics. We suggest that the protozoan Leishmania tarentolae can be used as an easy-to-handle microfactory for the rapid production of viral antigens to face emerging epidemics. We engineered L. tarentolae to express the SARS-CoV-2 receptor-binding domain (RBD) and we recorded the ability of the purified RBD antigen to detect SARS-CoV-2 infection in human sera, with a sensitivity and reproducibility comparable to that of a reference antigen produced in human cells. This is the first application of an antigen produced in L. tarentolae for the serodiagnosis of a Coronaviridae infection. On the basis of our results, we propose L. tarentolae as an effective system for viral antigen production, even in countries that lack high-technology cell factories.