Wearable sensor platforms for real-time monitoring and early warning of metabolic disorders in humans.

Nowadays, the prevalence of metabolic syndromes (MSs) has attracted increasing concerns as it is closely related to overweight and obesity, physical inactivity and overconsumption of energy, making the diagnosis and real-time monitoring of the physiological range essential and necessary for avoiding illness due to defects in the human body such as higher risk of cardiovascular disease, diabetes, stroke and diseases related to artery walls. However, the current sensing techniques are inconvenient and do not continuously monitor the health status of humans. Alternatively, the use of recent wearable device technology is a preferable method for the prevention of these diseases.

A Self-Assembled G-Quadruplex/Hemin DNAzyme-Driven DNA Walker Strategy for Sensitive and Rapid Detection of Lead Ions Based on Rolling Circle Amplification.

Herein, a sensitive biosensor is constructed based on a novel rolling circle amplification (RCA) for colorimetric quantification of lead ion (Pb). At the detection system, GR5 DNAzymes are modified on the surface of an immunomagnetic bead, and Pb is captured by the aptamer, inducing the disintegration of the GR5 DNAzyme and the release of the DNA walker. After the introduction of the template DNA, T4 DNA ligase, and phi29 DNA polymerase, an RCA is initiated for the sensitivity improvement of this method.

Immobilization of ssDNA on a metal-organic framework derived magnetic porous carbon (MPC) composite as a fluorescent sensing platform for the detection of arsenate ions.

In this work, we fabricated a metal-organic framework derived magnetic porous carbon (MPC) composite using a one-pot solid state template method. The formation of the synthesized composite was confirmed with various spectroscopic techniques, and it was proved that the composite can effectively quench the fluorescence of ssDNA. This property was utilized in the specific and efficient recognition of harmful arsenate ions.

Metal-Polydopamine Framework as an Effective Fluorescent Quencher for Highly Sensitive Detection of Hg(II) and Ag(I) Ions through Exonuclease III Activity.

In this paper, we propose a metal-polydopamine (MPDA) framework with a specific molecular probe which appears to be the most promising approach to a strong fluorescence quencher. The MPDA framework quenching ability toward various organic fluorophore such as aminoethylcoumarin acetate, 6-carboxyfluorescein (FAM), carboxyteramethylrhodamine, and Cy5 are used to establish a fluorescent biosensor that can selectively recognize Hg and Ag ions. The fluorescent quenching efficiency was sufficient to achieve more than 96%.

Fluorometric determination of lead(II) and mercury(II) based on their interaction with a complex formed between graphene oxide and a DNAzyme.

The authors have designed a DNAzyme where graphene oxide (GO) interacts with the ssDNA stem loop region. The DNAzyme strand and substrate strand are hybridized and bind to the surface of GO which act as a signal reporter, while GO act as a strong quencher. The presence of Pb(II) ion disturbs the GO-DNAzyme complex and causes internal cleavage of the DNAzyme complex.