Construction of a Au@MoS2 composite nanosheet biosensor for the ultrasensitive detection of a neurotransmitter and understanding of its mechanism based on DFT calculations

An electrochemical biosensor based on Au@MoS2 composite nanosheets was successfully prepared for the high-sensitivity detection of dopamine.

CRISPR/Cas12a-Based Assay for the Rapid and High-Sensitivity Detection of Streptococcus Agalactiae Colonization in Pregnant Women with Premature Rupture of Membrane

Background Streptococcus agalactiae or group B Streptococcus (GBS) is a leading infectious cause of neonatal morbidity and mortality. This study aims to establish a novel method, termed as the CRISPR-GBS assay, for the rapid and sensitive detection of GBS that is based on the clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated protein (Cas) system. Results The CRISPR-GBS assay detected GBS in the samples within 35 min. The limit of detection was as low as 5 copies/µL and showed no cross-reactivity with other microorganisms. The clinical performance was assessed using vaginal or cervical swab samples that were collected from 179 pregnant women with premature rupture of membrane. Compared with the culture-based matrix-assisted laser desorption ionization time-of-flight mass spectrometry method, the CRISPR-GBS assay demonstrated a sensitivity of 96.64% (144/149, 95% confidence interval [CI] = 92.39–98.56%) and a specificity of 100% (30/30, 95% CI = 88.65–100%). It also had a high concordance rate of 98.88% with the real-time fluorescence polymerase chain reaction assay. Conclusions The CRISPR-GBS assay can be used for rapid and high-sensitivity detection of GBS in a simple and cost-efficient manner; thus, it offers a novel method for intrapartum screening.

Advanced Optogenetic-Based Biosensing and Related Biomaterials

The ability to stimulate mammalian cells with light, brought along by optogenetic control, has significantly broadened our understanding of electrically excitable tissues. Backed by advanced (bio)materials, it has recently paved the way towards novel biosensing concepts supporting bio-analytics applications transversal to the main biomedical stream. The advancements concerning enabling biomaterials and related novel biosensing concepts involving optogenetics are reviewed with particular focus on the use of engineered cells for cell-based sensing platforms and the available toolbox (from mere actuators and reporters to novel multifunctional opto-chemogenetic tools) for optogenetic-enabled real-time cellular diagnostics and biosensor development. The key advantages of these modified cell-based biosensors concern both significantly faster (minutes instead of hours) and higher sensitivity detection of low concentrations of bioactive/toxic analytes (below the threshold concentrations in classical cellular sensors) as well as improved standardization as warranted by unified analytic platforms. These novel multimodal functional electro-optical label-free assays are reviewed among the key elements for optogenetic-based biosensing standardization. This focused review is a potential guide for materials researchers interested in biosensing based on light-responsive biomaterials and related analytic tools.