A highly selective and sensitive electrochemical sensor for dopamine based on functionalized multi walled carbon nanotubes and poly(N-methylaniline) composite

Dopamine (DA) is an important neurotransmitter used for diagnosing various diseases from its abnormal concentrations in human fluids. Herein, an electrochemical sensor based on a composite of re-doped poly(N-methylaniline) (rePNMA)...

Effectiveness of Disinfection with Chlorine Dioxide on Respiratory Transmitted, Enteric, and Bloodborne Viruses: A Narrative Synthesis

A viral spread occurrence such as the SARS-CoV-2 pandemic has prompted the evaluation of different disinfectants suitable for a wide range of environmental matrices. Chlorine dioxide (ClO2) represents one of the most-used virucidal agents in different settings effective against both enveloped and nonenveloped viruses. This narrative synthesis is focused on the effectiveness of ClO2 applied in healthcare and community settings in order to eliminate respiratory transmitted, enteric, and bloodborne viruses. Influenza viruses were reduced by 99.9% by 0.5–1.0 mg/L of ClO2 in less than 5 min. Higher concentration (20 mg/L) eliminated SARS-CoV-2 from sewage. ClO2 concentrations from 0.2 to 1.0 mg/L ensured at least a 99% viral reduction of AD40, HAV, Coxsackie B5 virus, and other enteric viruses in less than 30 min. Considering bloodborne viruses, 30 mg/L of ClO2 can eliminate them in 5 min. Bloodborne viruses (HIV-1, HCV, and HBV) may be completely eliminated from medical devices and human fluids after a treatment with 30 mg/L of ClO2 for 30 min. In conclusion, ClO2 is a versatile virucidal agent suitable for different environmental matrices.

A Critical Review of Carbon Quantum Dots: From Synthesis toward Applications in Electrochemical Biosensors for the Determination of a Depression-Related Neurotransmitter

Depression has become the leading cause of disability worldwide and is a global health burden. Quantitative assessment of depression-related neurotransmitter concentrations in human fluids is highly desirable for diagnosis, monitoring disease, and therapeutic interventions of depression. In this review, we focused on the latest strategies of CD-based electrochemical biosensors for detecting a depression-related neurotransmitter. We began this review with an overview of the microstructure, optical properties and cytotoxicity of CDs. Next, we introduced the development of synthetic methods of CDs, including the “Top-down” route and “Bottom-up” route. Finally, we highlighted detecting an application of CD-based electrochemical sensors in a depression-related neurotransmitter. Moreover, challenges and future perspectives on the recent progress of CD-based electrochemical sensors in depression-related neurotransmitter detection were discussed.

Electrospun Hybrid Microfibers of Polylactic Acid with Plasma Polypyrrole Particles with Ultrahydrophobic Surface for Biomedical Applications

This work presents a study on the formation of hybrid electrospun fibers of polylactic acid (PLA) with insoluble polypyrrole (PPy) particles inside with the objective to prepare ultrahydrophobic fibers for biomedical applications. Krebs-Ringer and phosphate-buffered saline solutions were used as test solutions of human fluids. The PPy particles were synthesized by plasma with diameter in the 60-1000 nm range and were suspended in a PLA-chloroform solution with a PPy/PLA = 0.027 mass ratio. PLA fibers with PPy particles inside were formed electrospinning this suspension obtaining diameters in the 0.12-9.0 µm range with average between 1.65 and 1.85 µm. Contact angles of the fibers with the test solutions were measured in the 113°-147° interval, most of them in the ultrahydrophobic (120°-150°) region. The lowest angles were obtained with particles synthesized at the lowest power (20 W) and were like those obtained on PLA fibers. The highest angles were measured on the fibers with the particles synthesized at the highest synthesis power (100 W), with difference up to 15°. This difference in the angles was correlated with the resonant ≈ C ≈ groups of the particles through the fiber ultraviolet absorption.

Colistin Resistance in Aeromonas spp.

The increase in the use of antimicrobials such as colistin for the treatment of infectious diseases has led to the appearance of Aeromonas strains resistant to this drug. However, resistance to colistin not only occurs in the clinical area but has also been determined in Aeromonas isolates from the environment or animals, which has been determined by the detection of mcr genes that confer a resistance mechanism to colistin. The variants mcr-1, mcr-3, and mcr-5 have been detected in the genus Aeromonas in animal, environmental, and human fluids samples. In this article, an overview of the resistance to colistin in Aeromonas is shown, as well as the generalities of this molecule and the recommended methods to determine colistin resistance to be used in some of the genus Aeromonas.