An innovative method to electrochemical branching of chitosan in the presence of copper nanocubics on the surface of glassy carbon and its electrical behaviour study: A new platform for pharmaceutical analysis using electrochemical sensors

Photoelectrochemical biosensor based on SiW12@CdS quantum dots for the highly sensitive detection of HPV 16 DNA

A highly sensitive biosensor for detecting HPV 16 DNA was prepared based on Keggin-type polyoxometalate (SiW₁₂)-grafted CdS quantum dots (SiW₁₂@CdS QDs) and colloidal gold nanoparticles (Au NPs), which exhibited remarkable selectivity and sensitivity upon target DNA detection because of its excellent photoelectrochemical (PEC) response. Here, an enhanced photoelectronic response ability was achieved with the strong association of SiW₁₂@CdS QDs by polyoxometalate modification, which was developed through a convenient hydrothermal process. Furthermore, on Au NP-modified indium tin oxide slides, a multiple-site tripodal DNA walker sensing platform coupled with T7 exonuclease was successfully fabricated with SiW₁₂@CdS QDs/NP DNA as a probe for detecting HPV 16 DNA. Due to the remarkable conductivity of Au NPs, the photosensitivity of the as-prepared biosensor was improved in an I3-/I- solution and avoided the use of other regents toxic to living organisms. Finally, under optimized conditions, the as-prepared biosensor protocol demonstrated wide linear ranges (15-130 nM), with a limit of detection of 0.8 nM and high selectivity, stability, and reproducibility. Moreover, the proposed PEC biosensor platform offers a reliable pathway for detecting other biological molecules with nano-functional materials.

A disposable electrochemical sensor based on single-walled carbon nanotubes for the determination of anticancer drug dasatinib

Dasatinib is an anticancer drug that treats acute lymphoblastic leukemia, chronic myelogenous leukemia, and prostate cancer with several side effects. In this research, we suggest nanoparticle-modified screen-printed electrodes (SPCEs) as disposable electrochemical sensors for fast quantification of dasatinib in pharmaceutical formulations. Carbon nanotubes, single-walled carbon nanotubes (SWCNT), graphene, and graphene oxide-modified SPCEs were characterized by scanning electron microscopy. The study also recommends SWCNT-modified SPCEs as the best-performing electrode for determining dasatinib, demonstrating an excellent boosting effect on the oxidation response of dasatinib. This was accomplished using the square-wave voltammetry method. After optimization of the pH condition, pH 5.0 Britton–Robinson buffer, SWCNT-modified SPCEs demonstrated 94% recovery with optimum electro-oxidation activity. The oxidation currents exhibited linear relation with dasatinib concentration in the 0.1–100 µM. Based on the results, a limit of detection of 0.06 µM was obtained in the standard solution. The SWCNT-modified SPCEs have been applied to analyze dasatinib in pharmaceutical tablet samples. The demonstrated performance beats all comparable standard analytical tools and presumably may be used for general drug quantitation in pharmaceutical tablets.

Graphical abstract

Carbon Nanomaterial-Based Drug Sensing Platforms Using State-of-the- Art Electroanalytical Techniques

Background:

Currently, nanotechnology and nanomaterials are considered as the most popular and outstanding research subjects in scientific fields ranging from environmental studies to drug analysis. Carbon nanomaterials such as carbon nanotubes, graphene, carbon nanofibers etc. and non-carbon nanomaterials such as quantum dots, metal nanoparticles, nanorods etc. are widely used in electrochemical drug analysis for sensor development. Main aim of drug analysis with sensors is developing fast, easy to use and sensitive methods. Electroanalytical techniques such as voltammetry, potentiometry, amperometry etc. which measure electrical parameters such as current or potential in an electrochemical cell are considered economical, highly sensitive and versatile techniques.

Methods:

Most recent researches and studies about electrochemical analysis of drugs with carbon-based nanomaterials were analyzed. Books and review articles about this topic were reviewed.

Results:

The most significant carbon-based nanomaterials and electroanalytical techniques were explained in detail. In addition to this; recent applications of electrochemical techniques with carbon nanomaterials in drug analysis was expressed comprehensively. Recent researches about electrochemical applications of carbon-based nanomaterials in drug sensing were given in a table.

Conclusion:

Nanotechnology provides opportunities to create functional materials, devices and systems using nanomaterials with advantageous features such as high surface area, improved electrode kinetics and higher catalytic activity. Electrochemistry is widely used in drug analysis for pharmaceutical and medical purposes. Carbon nanomaterials based electrochemical sensors are one of the most preferred methods for drug analysis with high sensitivity, low cost and rapid detection.

Gold-Carbon Nanocomposites for Environmental Contaminant Sensing

The environmental crisis, due to the rapid growth of the world population and globalisation, is a serious concern of this century. Nanoscience and nanotechnology play an important role in addressing a wide range of environmental issues with innovative and successful solutions. Identification and control of emerging chemical contaminants have received substantial interest in recent years. As a result, there is a need for reliable and rapid analytical tools capable of performing sample analysis with high sensitivity, broad selectivity, desired stability, and minimal sample handling for the detection, degradation, and removal of hazardous contaminants. In this review, various gold–carbon nanocomposites-based sensors/biosensors that have been developed thus far are explored. The electrochemical platforms, synthesis, diverse applications, and effective monitoring of environmental pollutants are investigated comparatively.