Assessing Immunity by Quantitative Measurement of SARS-CoV-2 IgG Antibodies in Fingerstick Samples.

COVID-19 has affected billions of people around the world directly or indirectly. The response to the pandemic has focused on preventing the spread of the disease and improving treatment options. Diagnostic technologies have played a key role in this response since the beginning of the pandemic.

A SERS aptasensor for sensitive and selective detection of bis(2-ethylhexyl) phthalate.

Bis(2-ethylhexyl) phthalate (DEHP) is an endocrine disruptor commonly present in plastic products, such as PVC tubes and water bottles. In this work, a surface enhanced Raman spectroscopy (SERS) based aptasensor was developed and utilized for rapid, easy, sensitive, and specific detection of trace DEHP. A DEHP aptamer was immobilized on magnetic particles.

Collection Method of SERS Active Nanoparticles for Sensitive and Precise Measurements.

Developing surface-enhanced Raman spectroscopy (SERS) based biosensors requires not only synthesizing SERS active nanoparticles or nanoprobes that produce intense signal but also collecting them in a consistent manner to obtain sensitive and precise measurements. Nanoprobes are commonly measured in solution; however, this approach has several disadvantages that can reduce sensitivity, such as probing only a small percentage of the nanoprobes present in the sample. In this work, a novel collection device was designed, built, and tested which consistently concentrates nanoprobes in a specific area to yield highly sensitive (femtomolar) and repeatable measurements.

Optimization of a Concanavalin A-based glucose sensor using fluorescence anisotropy.

To date, the dependent nature of the recognition and transduction mechanisms in optical glucose sensors based upon Concanavalin A (ConA) has tended to prevent the sensors' full potential from being realized. In this paper, these mechanisms are independently optimized for a given assay configuration in order to decrease the predictive error of a ConA-based glucose sensor and to give a more accurate demonstration of its potential. To this end, we used fluorescence anisotropy as the transduction mechanism to determine the binding of ConA to 4 kDa FITC-dextran by measuring the change in the rotational correlation lifetime between the bound and unbound populations.