A rapid and inexpensive 96-well DNA-extraction method from blood using silicon dioxide powder (Glassmilk).

We present a rapid high-throughput DNA extraction method for use with EDTA-anticoagulated blood using silicon dioxide (SiO) powder in a guanidine-HCl solution, hereinafter referred to as "Glassmilk." The method utilizes a 96-well deep-well plate, enabling DNA extraction from 96 samples in under 3 h. The method integrates cell lysis, washing, elution, and DNA storage within the same well, eliminating the need for DNA transfer.

Diagnostic Performance of Seven Commercial COVID-19 Serology Tests Available in South America.

Background: Although RT-qPCR remains the gold-standard for COVID-19 diagnosis, anti-SARS-CoV-2 serology-based assays have been widely used during 2020 as an alternative for individual and mass testing, and are currently used for seroprevalence studies.

Objective: To study the clinical performance of seven commercial serological tests for COVID-19 diagnosis available in South America.

Methods: We conducted a blind evaluation of five lateral-flow immunoassays (LFIA) and two enzyme-linked immunosorbent assays (ELISAs) for detecting anti-SARS-CoV-2 antibodies.