Metal-organic framework-based materials as an emerging platform for advanced electrochemical sensing

A near-infrared light-activated ratiometric photoelectrochemical aptasensor was fabricated for detection of carcinoembryonic antigen (CEA) coupling with upconversion nanoparticles (UCNPs)-semiconductor nanocrystals-based spatial-resolved technique on a homemade 3D printing device in which a self-regulating integrated electrode was designed for dual signal readout. The as-prepared NaYF4:Yb,Er UCNPs@CdTe nanocrystals were initially assembled on two adjacent photoelectrodes, then CEA aptamer 1 (A1) and capture DNA (CA) were modified onto two working photoelectrodes (WP1 and WP2) through covalent binding, respectively, and then gold nanoparticle-labeled CEA aptamer 2 (Au NP-A2) was immobilized on the surface of functional WP2 for the formation of double-stranded DNA. Upon target CEA introduction, the various concentrations of CEA were captured on the WP1, whereas the binding of the CEA with Au NP-A2 could be released from the WP2 thanks to the highly affinity of CEA toward A2. The dual signal readout with the "signal-off" of WP1 and "signal-on" of WP2 were employed for the spatial-resolved PEC (SR-PEC) strategy to detect CEA as an analytical model. Combining NaYF4:Yb,Er UCNPs@CdTe nanocrystals with spatial-resolved model on 3D printing device, the PEC ratiometric aptasensor based on steric hindrance effect and exciton-plasmon interactions (EPI) exhibited a linear range from 10.0 pg mL-1 to 5.0 ng mL-1 with a limit of detection of 4.8 pg mL-1 under 980 nm illumination. The SR-PEC ratiometric strategy showed acceptable stability and reproducibility with a superior anti-interference ability. This approach can provide the guidance for the design of ratiometric, multiplexed, and point-of-care biosensors.

Dual-Channel Photoelectrochemical Ratiometric Aptasensor with up-Converting Nanocrystals Using Spatial-Resolved Technique on Homemade 3D Printed Device

Superior corrosion resistance and self-healable epoxy coating pigmented with silanzied trianiline-intercalated graphene

Cellulose nanocrystals: Pretreatments, preparation strategies, and surface functionalization.

Improvement of anticorrosion ability of epoxy matrix in simulate marine environment by filled with superhydrophobic POSS-GO nanosheets.

The demand of precise assay of nucleic acids and other bioanalytes has been increasing enormously in various areas including point-of-care diagnostics, military, environmental monitoring and so on. Compared with other nucleic acid biosensors, the electrochemical nucleic acid biosensors possess a range of merits like amenable miniaturization, low costs and high sensitivity. Ratiometric electrochemical nucleic acid biosensors can overcome the inherent systematic errors of conventional electrochemical biosensors and enhance the reproducibility and credibility. This short review (with 81 refs.) summarizes the evolvements made in the area of nucleic acid-based biosensors based on ratiometric (electrochemiluminescent, electrochemical and photoelectrochemical) readout in the past few years. Many of the methods discussed here are based on the use of advanced nanomaterials such as quantum dots, graphitic carbon nitrides, graphene oxide, C-dots, gold nanoparticles, metal-organic frameworks, and respective nanohybrids. Three sections (on electrochemiluminescence, classical electrochemical and emerging photoelectrochemical systems) demonstrate the merits of ratiometric assays in various applications. The review ends with a section with conclusions and a discussion of future perspectives.

Nucleic acid-based ratiometric electrochemiluminescent, electrochemical and photoelectrochemical biosensors: a review

Ratiometric electrochemical sensors are being considered a significant advance in the fields of electroanalysis and are now attracting the attention of many research laboratories. Different from classic electrochemical sensors which typically adopt the absolute value of the signal as the output, ratiometric electrochemical sensors possess dual electrochemical signals and the quantitative measurement of target is based on the ratio of these two signals. The ratiometric signal readout mode provides a built-in correction factor to eliminate the contribution from non-specific interferences. Thus, greater reproducibility, accuracy and sensitivity are obtained, which are critical demands of the classic electrochemical sensor. In this review, we discuss recent advances in ratiometric electrochemical sensors. In addition, we give critical perspectives on the different design schemes, development status and application prospects for ratiometric electrochemical sensors.

A review of ratiometric electrochemical sensors: From design schemes to future prospects

Enhancement of the corrosion resistance of epoxy coating by highly stable 3, 4, 9, 10-perylene tetracarboxylic acid functionalized graphene.

As a typical carbon nanomaterial, graphene is frequently used as a modified material due to its excellent optical, electrical, and mechanical properties. Composite materials combining graphene with silicone rubber or silicone resin have significantly improved electrical, thermal, and mechanical properties compared with sole silicone rubber or silicone resin. This paper focused on the influence of graphene on the properties of silicone rubber and silicone resin in recent years. In addition, the application of graphene/silicone rubber composites in sensors and microwave absorption materials was also summarized. This review is expected to provide a systematic and fundamental understanding of the modification effect of graphene on silicone rubber and silicone resin, and look forward to the application of their composite materials in wearable electronic devices and other emerging fields, hope to inspire and perfect the future design of composites and expand their applications.

Effects of graphene on various properties and applications of silicone rubber and silicone resin

Food safety and regulation of consumer welfare are of great concern, so it is necessary to be able to detect pathogenic bacteria quickly and effectively. Although traditional methods of pathogen de...

Hui Zeng

Papers

Nucleic acid-based ratiometric electrochemiluminescent, electrochemical and photoelectrochemical biosensors: a review

A review of ratiometric electrochemical sensors: From design schemes to future prospects

Enhancement of the corrosion resistance of epoxy coating by highly stable 3, 4, 9, 10-perylene tetracarboxylic acid functionalized graphene.

Effects of graphene on various properties and applications of silicone rubber and silicone resin

Advances in Portable Visual Detection of Pathogenic Bacteria