Cationic copolymer and crowding agent have a cooperative effect on a Na-dependent DNAzyme.

DNAzymes are promising agents for theranostics and biosensors. Sodium dependent DNAzymes have been developed for sensing and imaging of Na, but these DNAzymes have low catalytic activity. Herein, we demonstrate that a molecular crowded environment containing 10 to 40 wt% PEG enhanced the catalytic activity of a Na-dependent DNAzyme, EtNa, although dextran did not.

Label free electrochemical DNA biosensor for COVID-19 diagnosis.

The COVID-19 pandemic has significantly increased the development of the development of point-of-care (POC) diagnostic tools because they can serve as useful tools for detecting and controlling spread of the disease. Most current methods require sophisticated laboratory instruments and specialists to provide reliable, cost-effective, specific, and sensitive POC testing for COVID-19 diagnosis. Here, a smartphone-assisted Sensit Smart potentiostat (PalmSens) was integrated with a paper-based electrochemical sensor to detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

Label-free detection of HPV mRNA with an artificial chaperone-enhanced MNAzyme (ACEzyme)-based electrochemical sensor.

Nucleic acid biosensors for point-of-care (POC) diagnostic applications are highly desirable. The ability to detect DNA and RNA in a simple, rapid, affordable and portable format leads to a range of important applications for early screening in the field of disease monitoring and management. Herein, we report the development of an isothermal, label-free electrochemical biosensor that was designed on the basis of target-driven MNAzyme cleavage activity.

One-step isothermal RNA detection with LNA-modified MNAzymes chaperoned by cationic copolymer.

RNA detection permits early diagnosis of several infectious diseases and cancers, which prevent propagation of diseases and improve treatment efficacy. However, standard technique for RNA detection such as reverse transcription-quantitative polymerase chain reaction has complicated procedure and requires well-trained personnel and specialized lab equipment. These shortcomings limit the application for point-of-care analysis which is critical for rapid and effective disease management.

Artificial chaperones: From materials designs to applications.

Biological macromolecules must fold into native structures to gain functional activities. In living cells, proteins called molecular chaperones mediate productive folding by preventing undesired interactions and aggregation and by facilitating refolding of misfolded macromolecules into their bioactive forms. Inspired by natural molecular chaperones, artificial chaperones that mimic some features of their biological counterparts have been designed.

Cationic copolymer enhances 8-17 DNAzyme and MNAzyme activities.

DNAzymes are DNA molecules capable of catalytic activity. The catalytic core of DNAzymes can be separated and conjugated with target binding arms to create allosteric DNAzymes known as multi-component nucleic acid enzymes (MNAzymes). Two widely used DNAzymes are the 10-23 and the 8-17 DNAzymes.

Cationic copolymer-chaperoned DNAzyme sensor for microRNA detection.

Multi-component nucleic acid enzymes (MNAzymes) are allosteric deoxyribozymes that are activated upon binding of a specific nucleic acid effector. MNAzyme activity is limited due to an insufficient assembly of the MNAzyme and its turnover. In this work, we describe the successful improvement of MNAzyme reactivity and selectivity by addition of cationic copolymers, which exhibit nucleic acid chaperone-like activity.

Cationic copolymer-chaperoned short-armed 10-23 DNAzymes.

The cationic copolymer poly(L-lysine)--dextran (PLL--Dex) has nucleic acid chaperone-like activity. The copolymer facilitates both DNA hybridization and strand exchange reactions. For these reasons, DNA-based enzyme (DNAzyme) activity is enhanced in the presence of copolymer.

Turning hydrophilic bacteria into biorenewable hydrophobic material with potential antimicrobial activity via interaction with chitosan.

Alteration of a bacteriocin-producing hydrophilic bacterium, Lactococcus lactis IO-1, into a hydrophobic material with potential antimicrobial activity using chitosan was investigated and compared with five other bacterial species with industrial importance. The negatively charged bacterial cells were neutralized by positively charged chitosan, resulting in a significant increase in the hydrophobicity of the bacterial cell surface. The largest Gram-positive B.