Platinum-perovskite nanocomposite-based Exosensor for specific detection of prostate cancer in clinical settings.

Exosomes, extracellular vesicles (EVs) with an average size of 50-150 nm, transfer various biomolecules and exchange signaling molecules between cells in a paracrine manner. Molecular investigations have revealed that EVs can reflect real-time metabolic changes in normal- and cancer-origin cells and thus harbor valid diagnostic biomarkers. Despite these advantages, the detection of low concentrations of cancer cell EVs in biological fluids is still a great challenge. Here, a new electrochemical Exosensor based on platinum-perovskite is developed for the direct detection of EVs using a biotinylated monoclonal CD63 antibody as a capture element. The label-free method exhibited higher sensitivity with a lower limit of quantification of 2000 EVs/µL with a dynamic linear range (LDR) of 2000 to 14,000 EVs/µL compared with other available methods. To enhance the selectivity of detection, EVs were simultaneously sandwiched between secondary antibodies of PSA (prostate-specific antigen), as an FDA-approved prostate cancer biomarker. Data indicated that this Exosensor can distinguish normal and cancer EVs in samples from healthy individuals and prostate cancer patients. Taken together, this technology offers a unique approach to label-free quantification of EVs and cancer detection in the early stages.

Recent trends in layered double hydroxides based electrochemical and optical (bio)sensors for screening of emerging pharmaceutical compounds.

The rapid expansion of the human population has given rise to new environmental and biomedical concerns, contributing to different advancements in the pharmaceutical industry. In the field of analytical chemistry over the last few years, layered double hydroxides (LDHs) have drawn significant attention, owing to their extraordinary properties. Furthermore, the novel advancement of LDH-based optical and electrochemical platforms to detect different pharmaceutical materials has acquired substantial attention because of their outstanding specificity, actual-time controlling, and user-friendliness. This review aims to recapitulate advanced LDHs-based optical and electrochemical sensors and biosensors to identify and measure important pharmaceutical compounds, such as anti-depressant, anti-inflammatory, anti-viral, anti-bacterial, anti-cancer, and anti-fungal drugs. Additionally, fundamental parameters, namely interactions between sensor and analyte, design rationale, classification, selectivity, and specificity are considered. Finally, the development of high-efficiency techniques for optical and electrochemical sensors and biosensors is featured to deliver scientists and readers a complete toolbox to identify a broad scope of pharmaceutical substances. Our goals are: (i) to elucidate the characteristics and capabilities of available LDHs for the identification of pharmaceutical compounds; and (ii) to deliver instances of the feasible opportunities that the existing devices have for the developed sensing of pharmaceuticals regarding the protection of ecosystems and human health at the global level.

Electrochemical and optical (bio)sensors for analysis of antibiotic residuals.

Antibiotic residuals in foods may lead to crucial health and safety issues in the human body. Rapid and in-time analysis of antibiotics using simple and sensitive techniques is in high demand. Among the most commonly applicable modalities, chromatography-based techniques like HPLC and LC-MS, along with immunological approaches, particularly ELISA have been exampled in the analysis of antibiotics. Despite being highly sensitive, these methods are considerably time-consuming, thus the presence of skilled personnel and costly equipment is essential. Nanomaterial-based (bio)sensors, however, are de novo analytical equipment with some beneficial characteristics, such as simplicity, low price, on-site, high accuracy, and sensitivity for the detection of analytes. This review aimed to collect the latest developments in NM-based sensors and biosensors for the observation of highly used antibiotics like Vancomycin (Van), Linezolid (Lin), and Clindamycin (Clin). The current challenges and developmental perspectives are also debated in detail for future research directions.

Electrochemical biosensors in exosome analysis; a short journey to the present and future trends in early-stage evaluation of cancers.

The tumor microenvironment consists of a multiplicity of cells such as cancer cells, fibroblasts, endothelial cells, and immune cells within the specific parenchyma. It has been indicated that cancer cells can educate other cells within the tumor niche in a paracrine manner by the release of nano-sized extracellular vesicles namely exosomes (Exo), resulting in accelerated tumor mass growth. It is suggested that exosomal cargo with remarkable information can reflect any changes in metabolic and proteomic profiles in parent tumor cells. Therefore, exosomes can be touted as prognostic, diagnostic, and therapeutic elements with specific biomarkers in patients with different tumor types. Despite the advantages, conventional exosome separation and purification protocols are time-consuming and laborious with low abnormal morphology and purity rate. During the last decades, biosensor-based modalities, as emerging instruments, have been used to detect and analyze Exo in biofluids. Due to suitable specificity, sensitivity, and real-time readout, biosensors became promising approaches for the analysis of Exo in in vitro and in vivo settings. The inherent advantages and superiority of electrochemical biosensors in the determination of tumor grade based on exosomal cargo and profile were also debated. Present and future challenges were also discussed related to the application of electrochemical biosensors in the clinical setting. In this review, the early detection of several cancer types associated with ovaries, breast, brain, colon, lungs, T and B lymphocytes, liver and rare types of cancers were debated in association with released exosomes.

Advances in layered double hydroxide based labels for signal amplification in ultrasensitive electrochemical and optical affinity biosensors of glucose.

Since the development of enzyme electrodes, the research area of glucose biosensing has seen outstanding progress and improvement. Numerous sensing platforms have been developed based on different immobilization techniques and improved electron transfer between the enzyme and electrode. Interestingly, these platforms have consistently used innovative nanostructures and nanocomposites. In recent years, layered double hydroxides (LDHs) have become key tools in the field of analytical chemistry owing to their outstanding features and benefits, such as facile synthesis, cost-effectiveness, substantial surface area, excellent catalytic performance, and biocompatibility. LDHs are often synthesized as nanomaterial composites or manufactured with specific three-dimensional structures. The purpose of this review is to illustrate the biosensing prospects of LDH-based glucose sensors and the need for improvement. First, various clinical and conventional approaches for glucose determination are discussed. The definitions, types, and various synthetic methodologies of LDHs are then explained. Subsequently, we discuss the various research studies regarding LDH-based electrochemical and optical assays, focusing on modified systems, improved electron transfers pathways (through developments in surface science), and different sensing designs based on nanomaterials. Finally, a summary of the current limitations and future challenges in glucose analysis is described, which may facilitate further development and applications.