Sensing of nitric oxide using a glassy carbon electrode modified with an electrocatalytic film composed of dihexadecyl hydrogen phosphate, platinum nanoparticles, and acetylene black

Application of surfactants in the electrochemical sensing and biosensing of biomolecules and drug molecules

Realizing sensitive and efficient detection of biomolecules and drug molecules is of great significance. Among the detection methods that have been proposed, electrochemical sensing is favored for its outstanding advantages such as simple operation, low cost, fast response and high sensitivity. The unique structure and properties of surfactants have led to a wide range of applications in the field of electrochemical sensors and biosensors for biomolecules and drug molecules. Through the comparative analysis of reported works, this paper summarizes the application modes of surfactants in electrochemical sensors and biosensors for biomolecules and drug molecules, explores the possible electrocatalytic mechanism of their action, and looks forward to the development trend of their applications. This review is expected to provide some new ideas for subsequent related research work.

Carbon nanotube-interconnected ruthenium phthalocyanine nanoparticles used for real-time monitoring of nitric oxide released from vascular endothelial barrier model

Real-time monitoring of nitric oxide (NO) is of great importance in diagnosing the physiological functions of neurotransmission, cardiovascular, and immune systems. This study reports the carbon nanotube-interconnected ruthenium phthalocyanine nanoparticle nanocomposite and its applicability in construction of an electrochemical platform, which could real-time detect NO released from the vascular endothelial barrier (VEB) model in cell culture medium. The nanocomposite exhibits regular morphology, uniform particle size, and excellent electro-catalytic activity to electrochemical oxidation of NO. Under optimal conditions, the electrochemical device has high sensitivity (0.871 μA μM-1) and can selectively detect NO down to the concentration of 6 × 10-10 M. The human brain microvascular endothelial cells were cultured onto the Transwell support to construct the VEB model. Upon stimulated by L-arginine, NO produced by the VEB diffuses into the bottom chamber of the Transwell, and is real-time monitored by the electrochemical device. Moreover, evaluation of the NO inhibition by drug is realized using the electrochemical device-Transwell platform. This simple and sensitive platform would be of great interesting for evaluating the endothelial function or its pathological states, and screening the related drugs or chemicals.

An Amperometric Biomedical Sensor for the Determination of Homocysteine Using Gold Nanoparticles and Acetylene Black-Dihexadecyl Phosphate-Modified Glassy Carbon Electrode

A novel nanocomposite film composed of gold nanoparticles and acetylene black-dihexadecyl phosphate was fabricated and modified on the surface of a glassy carbon electrode through a simple and controllable dropping and electropolymerization method. The nanocomposite film electrode showed a good electrocatalytic response to the oxidation of homocysteine and can work as an amperometric biomedical sensor for homocysteine. With the aid of scanning electron microscopy, energy dispersive X-ray technology and electrochemical impedance spectroscopy, the sensing interface was characterized, and the sensing mechanism was discussed. Under optimal conditions, the oxidation peak current of homocysteine was linearly increased with its concentration in the range of 3.0 µmol/L~1.0 mmol/L, and a sensitivity of 18 nA/(μmol/L) was obtained. Furthermore, the detection limit was determined as 0.6 µmol/L, and the response time was detected as 3 s. Applying the nanocomposite film electrode for monitoring the homocysteine in human blood serum, the results were satisfactory.

Single-atom Ni-N4 provides a robust cellular NO sensor

Nitric oxide (NO) has been implicated in a variety of physiological and pathological processes. Monitoring cellular levels of NO requires a sensor to feature adequate sensitivity, transient recording ability and biocompatibility. Herein we report a single-atom catalysts (SACs)-based electrochemical sensor for the detection of NO in live cellular environment. The system employs nickel single atoms anchored on N-doped hollow carbon spheres (Ni SACs/N-C) that act as an excellent catalyst for electrochemical oxidation of NO. Notably, Ni SACs/N-C shows superior electrocatalytic performance to the commonly used Ni based nanomaterials, attributing from the greatly reduced Gibbs free energy that are required for Ni SACs/N-C in activating NO oxidation. Moreover, Ni SACs-based flexible and stretchable sensor shows high biocompatibility and low nanomolar sensitivity, enabling the real-time monitoring of NO release from cells upon drug and stretch stimulation. Our results demonstrate a promising means of using SACs for electrochemical sensing applications.

The monitoring of nitric oxide is important to a number of disease states and biomedical applications. Here, the authors report on a single nickel atom catalyst based sensor for detecting nitric oxide production from cells.

Design and Electrochemical Study of Platinum-Based Nanomaterials for Sensitive Detection of Nitric Oxide in Biomedical Applications

The extensive physiological and regulatory roles of nitric oxide (NO) have spurred the development of NO sensors, which are of critical importance in neuroscience and various medical applications. The development of electrochemical NO sensors is of significant importance, and has garnered a tremendous amount of attention due to their high sensitivity and selectivity, rapid response, low cost, miniaturization, and the possibility of real-time monitoring. Nanostructured platinum (Pt)-based materials have attracted considerable interest regarding their use in the design of electrochemical sensors for the detection of NO, due to their unique properties and the potential for new and innovative applications. This review focuses primarily on advances and insights into the utilization of nanostructured Pt-based electrode materials, such as nanoporous Pt, Pt and PtAu nanoparticles, PtAu nanoparticle/reduced graphene oxide (rGO), and PtW nanoparticle/rGO-ionic liquid (IL) nanocomposites, for the detection of NO. The design, fabrication, characterization, and integration of electrochemical NO sensing performance, selectivity, and durability are addressed. The attractive electrochemical properties of Pt-based nanomaterials have great potential for increasing the competitiveness of these new sensors and open up new opportunities in the creation of novel NO-sensing technologies for biological and medical applications.

Nanomaterials-based electrochemical detection of chemical contaminants

Recent advances in the development of nanomaterials-based electrochemical sensors for environmental monitoring and food safety applications are assessed.

Square-wave adsorptive stripping voltammetric determination of nanomolar levels of bezafibrate using a glassy carbon electrode modified with multi-walled carbon nanotubes within a dihexadecyl hydrogen phosphate film

A glassy carbon electrode modified with carbon nanotubes is applied for bezafibrate sensing.

Freestanding graphene paper decorated with 2D-assembly of Au@Pt nanoparticles as flexible biosensors to monitor live cell secretion of nitric oxide

We report the development of a new type of flexible electrochemical biosensors based on graphene paper loaded with closely-packed Au@Pt core-shell nanoparticles as a freestanding cell culture substrate for real-time monitoring cell secretion of nitric oxide. The hybrid electrode was fabricated through a modular approach in which 2D-assembly of nanoparticles formed at the oil-water interface was transferred onto graphene paper by dip-coating. We have shown that the independently optimized metal nanostructures and graphene paper were integrated into functional electrodes with high electrocatalytic activity. When used for the detection of nitric oxide, the flexible electrodes have demonstrated high sensitivity, a wide linear range, and a low detection limit, which, in combination with its biocompatibility, offer unique opportunities for the real-time monitoring of nitric oxide secretion by human endothelial vein cells grown on the electrode. These interesting findings collectively demonstrate the potential of our modular approach for designing high-performance flexible electrodes with tailored surface properties.