Label-free supersandwich electrogenerated chemiluminescence biosensor for the determination of the HIV gene

Biosensors for waterborne virus detection: Challenges and strategies

Waterborne viruses that can be harmful to human health pose significant challenges globally, affecting health care systems and the economy. Identifying these waterborne pathogens is essential for preventing diseases and protecting public health. However, handling complex samples such as human and wastewater can be challenging due to their dynamic and complex composition and the ultralow concentration of target analytes. This review presents a comprehensive overview of the latest breakthroughs in waterborne virus biosensors. It begins by highlighting several promising strategies that enhance the sensing performance of optical and electrochemical biosensors in human samples. These strategies include optimizing bioreceptor selection, transduction elements, signal amplification, and integrated sensing systems. Furthermore, the insights gained from biosensing waterborne viruses in human samples are applied to improve biosensing in wastewater, with a particular focus on sampling and sample pretreatment due to the dispersion characteristics of waterborne viruses in wastewater. This review suggests that implementing a comprehensive system that integrates the entire waterborne virus detection process with high-accuracy analysis could enhance virus monitoring. These findings provide valuable insights for improving the effectiveness of waterborne virus detection, which could have significant implications for public health and environmental management.

Recent advances and challenges in developing electrochemiluminescence biosensors for health analysis

This Feature Article simply introduces principles and mechanisms of electrochemiluminescence (ECL) biosensors for the determination of biomarkers and highlights recent advances of ECL biosensors on key aspects including new ECL reagents and materials, new biological recognition elements, and emerging construction biointerfacial strategies with illustrative examples and a critical eye on pitfalls and discusses challenges and perspectives of ECL biosensors for health analysis.

Nanobioconjugates for Signal Amplification in Electrochemical Biosensing

Nanobioconjugates are hybrid materials that result from the coalescence of biomolecules and nanomaterials. They have emerged as a strategy to amplify the signal response in the biosensor field with the potential to enhance the sensitivity and detection limits of analytical assays. This critical review collects a myriad of strategies for the development of nanobioconjugates based on the conjugation of proteins, antibodies, carbohydrates, and DNA/RNA with noble metals, quantum dots, carbon- and magnetic-based nanomaterials, polymers, and complexes. It first discusses nanobioconjugates assembly and characterization to focus on the strategies to amplify a biorecognition event in biosensing, including molecular-, enzymatic-, and electroactive complex-based approaches. It provides some examples, current challenges, and future perspectives of nanobioconjugates for the amplification of signals in electrochemical biosensing.

Amplified fluorescent sensing of DNA using luminescent carbon dots and AuNPs/GO as a sensing platform: A novel coupling of FRET and DNA hybridization for homogeneous HIV-1 gene detection at femtomolar level

The demand for simple, sensitive, affordable, and selective DNA biosensors is willing, due to the important role of DNA detection in the areas of disease diagnostics, environment monitoring and food safety. The presented work is devoted to the fabrication of an ultrasensitive homogeneous biosensor for the detection of DNA sequences related to HIV based on fluorescence resonance energy transfer(FRET) between carbon dots(CDs) and AuNPs as nanoquenchers. CDs as fluorophore with average size 3-4nm were prepared by hydrothermal treatment of histidine. In this respect, the hybridization was occurring between the assemblies of fluorescence CDs functionalized 5-amino-labeled oligonucleotides as capture probe and label free oligonucleotides as detection probe. Due to strong fluorescence and good biocompatibility of CDs, the capture probe was covalently conjugated to CDs. In the presence of the target probe, the association between capture probe-CDs and detection probe is stronger than that between capture probe-CDs and AuNPs, leading to the release of the capture probe-CDs from AuNPs, resulting in the recovery of the fluorescence of CDs. This oligonucleotides detection probe was observed to detect target oligonucleotides specifically and sensitively in a linear range from 50.0fM to 1.0nM with a detection limit of 15fM. Furthermore, the sensitivity of this FRET strategy amplified using AuNPs/graphene oxide nanocomposite as quencher. The Sensor response indicates only the complementary sequence showing an obvious change signal in comparison to non-complementary and two bases mismatched sequences. Moreover, satisfactory results from determination of HIV DNA target in human serum were obtained showing great potential of the proposed method for real sample analysis. The proposed biosensor with highly biocompatibility and nontoxicity, can be developed for detection of other DNA biomarkers.