Biosensors and Bioelectronics: X最新文献

As efficient biocatalysts, enzymes can catalyze various reactions under mild conditions, and have excellent substrate specificity and selectivity. However, the high cost of preparation and difficulty in recovery of natural enzymes have seriously hindered their practical applications. Compared with natural enzymes, the nanozymes with enzyme-like activities have unique advantages in activity regulation, high stability and large-scale preparation. Nanozymes have been widely concerned in the fields of biological detection, medical treatment and cellular immunity, and have a great application potential in the sensor array field. The sensor arrays have recently received an increasing attention due to their applicability in complex biological analysis and diagnosis. This review first summarizes the classification of nanozymes and their corresponding enzyme-like activities. The applications of nanozymes in various sensor arrays are then introduced, in particular, the detecting small molecule, protein and pesticide as nonspecific recognition receptors are addressed. Finally, the future development directions and design principles are prospected for overcoming current challenges, thus providing more opportunities for the application of nanozyme sensor arrays.

Nanozymes and aptamers have long been integral parts of the biosensing field. Recent advancements in these areas have culminated in the creation of a novel class of biosensors known as nanozyme-based aptasensors. In these sensors, aptamers confer specificity to the target analyte, while nanozymes function as transducers, converting a binding event (the binding of the aptamer to its target) into a detectable signal. Despite their promising potential and diverse applications, the detection of small-target molecules, like antibiotics, toxins, metal ions, etc., using nanozyme-based aptasensors remains challenging. This perspective focuses on the obstacles associated with the selection of aptamers for small targets, the design and efficiency of nanozymes, and their integration into functional sensors. In the current perspective, we outline the key challenges and propose various strategies to overcome these hurdles, drawing lessons from past failures to inspire further research for detection of small-target molecules. By incorporating these measures, the performance of nanozyme-based aptasensors to detect small-target molecules can be significantly improved, leading to more effective detection platforms with enhanced sensitivity in the near future.

This research aims to improve the output power of self-pumping glucose enzymatic biofuel cell (EBFC) and modifying the anode. Adding a fixed ratio of methyl red-chitosan (MR-CS) can effectively improve the EBFC efficiency and stability. In addition, chitosan can be obtained from discarded crustacean fishery waste objects such as shrimp and oysters, are also significant to the use of environmentally friendly materials. The catalyst was immobilized on pyrenecarboxaldehyde (PCA), polyethyleneimine (PEI) and multi-wall carbon nanotubes (MWCNT) and combined with glucose oxidase (GOx). Finally, the [PCA/GOx]/PEI/Nafion solution/MWCNT/[MR-CS] catalyst was immobilized on the carbon cloth. Experimental analysis was progressed under the preparation of enzyme-supported electrode to observe the feasibility of the anode electrode. Experiment including Fourier transform infrared spectroscopy (FTIR) to analyze the distribution of functional groups after modification of the carbon cloth electrode, and through the comparison of the ultraviolet–visible spectrometer (UV–Vis), it can be known that the concentration ratio of [MR-CS] is 1:5, the glucose oxidase load can be maximized. Electrochemical analysis (Cyclic Voltammetry, CV) measures the activity of the maximum reaction of the anode material and the corresponding redox peak, and scanning electron microscope (SEM) observes the surface morphology of the modified electrode. Self-pumping glucose enzymatic biofuel cell module was assembled and examined, the results showed that the maximum output power density (MPD) was 2.64 mW/cm².

The detection of clinically important disease-specific biomarkers such as proteins, nucleic acids, antibodies, enzymes, viruses and circulating tumor cells is essential for understanding their role in disease diagnosis and prognosis. Thus, current clinical research aims at developing a biosensor for the ultrasensitive, reliable, and specific detection of these low-abundant biomolecules in bodily fluids including urine, saliva, and blood. Electrochemical biosensors are powerful devices that make it simple, quick, and affordable the detection of disease biomarkers in clinical diagnostics Peptides epitomize an intriguing group of biorecognition elements that can be linked to electrochemical transducers owing to their stability and selectivity concerning a target analyte. Moreover, they are amenable to facile synthesis and modification with designated functional groups, rendering them appropriate for the creation of innovative architectures for electrochemical biosensing systems. In this review, we provided an outline of the most recent developments in material designs, recognition systems, and strategy advancements related to fabricating peptide-based electrochemical biosensors for disease biomarker detection.

Detecting bacteria is essential in managing significant health concerns as it enables timely intervention, reducing complications and improving patient outcomes, particularly in treating common infections that necessitate precise identification for effective symptom management. Enterococcus species represent a notable threat in hospital-acquired infections and urinary tract infections (UTIs), given the increasing prevalence of strains resistant to multiple antibiotics, unresponsive to standard therapies, and carrying various virulence factors. Traditional approaches to identifying Enterococcus faecalis (E. faecalis) have limitations, including prolonged processing times, limited sensitivity, and the potential for false positive results. While Polymerase Chain Reaction (PCR) is a valuable tool, it is susceptible to contamination and variations in DNA concentration. The emerging technique of Photoelectrochemical (PEC) holds promise for enhancing E. faecalis detection by leveraging photogenerated electrons and holes. This study introduces a rapid and precise approach utilizing a light-assisted electrochemical biosensor featuring a glassy carbon electrode modified with a nanocomposite of gold-coated iron oxide and carbon dots (Au@Fe₃O₄/CDs). The nanocomposite was successfully synthesized and underwent thorough characterization. The investigation has a detection range from 1 to 14 CFU mL⁻¹, along with a notably low limit of detection (LOD: 3 CFU mL⁻¹, LOQ: 10 CFU mL⁻¹). Rigorous examination of real-world samples such as food, water, and soil demonstrated exceptional specificity, reproducibility, and long-term stability of the sensor. The applications of the Au@Fe₃O₄/CDs nanocomposite in PEC processes underscore the potential of this innovative approach in addressing health concerns associated with bacterial infections and delivering real-time impacts for both healthcare and environmental domains.

Early-stage detection of any cancer significantly improves the survival rates by enabling clinicians to design simpler and more effective treatment options, leading to a cure or remission. Early diagnosis of ovarian cancer, the leading cause of gynaecological cancer related mortalities, relies heavily on accurate detection of the serum biomarker CA125. This work presents a simple rGO/monoclonal antibody (mAB)/bovine serum albumin (BSA) based 2-port resistive sensor for CA125. The binding of mAB on rGO was confirmed by atomic force microscopy which showed increase in thickness of the device from 1.4 nm to approximately 40–60 nm after the mAB anchored on the device. FESEM further confirmed the morphologies of rGO, rGO/mAB, and rGO/mAB/CA125. The sensor exhibited impressive response ranging from 1.28% to 113.4% for 1 pg/mL to 300 ng/mL CA125. Notably, the rGO/mAB/BSA sensor displayed high selectivity towards CA125 and a readout circuit was designed, assembled, and tested with the sensors to get a portable device for detecting CA125. The developed sensors were tested with 9 clinical samples and were found to be determining the CA125 concentration accurately.

The landscape of biosensing technologies has undergone a significant transformation, with a particular emphasis on instant screening tests (ISTs) tailored for home and community settings. These tests play a crucial role in enabling rapid detection, monitoring, and management of a varied range of health conditions, including infectious diseases, chronic illnesses, and environmental exposures. This letter provides a brief exploration of the various key aspects of biosensing methodologies and technologies designed to address the unique challenges and opportunities inherent in ISTs. By exploring crucial advancements and emerging trends, it highlights the transformative potential of these innovations in enhancing healthcare accessibility and empowering individuals to take proactive control of their well-being.