Search Results (291)

Background/Objectives: Kidney cancer (RC) is a significant global health burden. Renal cell carcinoma (RCC) is the most common form of kidney cancer. Its predominant histological subtype is clear cell renal cell carcinoma (ccRCC), which is frequently diagnosed at an advanced local stage or with metastases. Detecting cancer at an early stage significantly increases the likelihood of a cure; therefore, research on new markers and a thorough understanding of tumor biology are essential. This study investigated the significance of aromatase (ARO), cathepsin S (CTSS), and matrix metalloproteinase 1 (MMP-1) as potential biomarkers in ccRCC. Methods: ARO, CTSS, and MMP-1 concentrations in plasma were determined using SPRi biosensors. Appropriate antibodies were used as biorecognition molecules in the biosensors. The samples analyzed came from 60 patients with histopathologically confirmed clear cell renal cell carcinoma (ccRCC) and from 26 patients diagnosed with chronic cystitis or benign prostatic hyperplasia (BPH). Results: A statistically significant increase (p < 0.00001) in the concentration of all proteins compared with the control samples was observed at the T3–T4 stage. The ARO concentration was already statistically significantly higher at the T1–T2 stage (p < 0.00001). The ROC curve for aromatase demonstrated high sensitivity and specificity for detecting ccRCC, with a cut-off point of 7.53 ng mL⁻¹. A moderate positive correlation was also found between the concentrations of the three tested substances in renal cancer, which may indicate potential interactions in the tumor’s pathogenesis. Conclusions: SPRI testing has been shown to be an alternative to standard methods for detecting potential ccRCC markers. The biosensors used in the study can simultaneously determine ARO, CTSS, and MMP-1. The results obtained suggest the potential importance of these proteins in the development of ccRCC, and our work proposes a new diagnostic technique that may aid in the diagnosis of ccRCC. Full article

Microparticle detection technology uses materials that can specifically recognize complex biostructures, such as antibodies and aptamers, as trapping agents. The development of antibody production technology and simplification of sensing signal output methods have facilitated commercialization of disposable biosensors, making rapid diagnosis possible. Although this contributed to the early resolution of pandemics, traditional biosensors face issues with sensitivity, durability, and rapid response times. We aimed to fabricate microspaces using metallic materials to further enhance durability of mold fabrication technologies, such as molecular imprinting. Low-damage metal deposition was performed on target protozoa and Norovirus-like particles (NoV-LPs) to produce thin metallic films that adhere to the material. The procedure for fitting the object into the bio structured space formed on the thin metal film took less than a minute, and sensitivity was 10 fg/mL for NoV-LPs. Furthermore, because it was a metal film, no decrease in reactivity was observed even when the same substrate was stored at room temperature and reused repeatedly after fabrication. These findings underscore the potential of integrating stable metallic structures with bio-recognition elements to significantly enhance robustness and reliability of environmental monitoring. This contributes to public health strategies aimed at early detection and containment of infectious diseases. Full article

Infectious diseases caused by bacterial and viral pathogens remain a major global threat, particularly in areas with limited diagnostic resources. Conventional optical techniques are time-consuming, prone to operator errors, and require sophisticated instruments. Colorimetric biosensors, which convert biorecognitive processes into visible color changes, enable simple and low-cost point-of-care testing. Artificial intelligence (AI) enhances decision-making by enabling learning, training, and pattern recognition. Machine learning (ML) and deep learning (DL) improve diagnostic accuracy, but they do not autonomously adapt and are pre-trained on complex color variation, whereas traditional computer-based methods lack analysis ability. This review summarizes major pathogens in terms of their types, toxicity, and infection-related mortality, while highlighting research gaps between conventional optical biosensors and emerging AI-assisted colorimetric approaches. Recent advances in AI models, such as ML and DL algorithms, are discussed with a focus on their applications to clinical samples over the past five years. Finally, we propose a prospective direction for developing robust, explainable, and smartphone-compatible AI-assisted assays to support rapid, accurate, and user-friendly pathogen detection for health and clinical applications. This review provides a comprehensive overview of the AI models available to assist physicians and researchers in selecting the most effective method for pathogen detection. Full article

Organic field-effect transistor (OFET) biosensors have emerged as a transformative technology for clinical biomarker detection, offering unprecedented sensitivity, selectivity, and versatility in point-of-care (POC) diagnostics. This review examines the fundamental principles, materials innovations, device architectures, and clinical applications of OFET-based biosensing platforms. The unique properties of organic semiconductors, combined with advanced biorecognition strategies, enable the detection of clinically relevant biomarkers at low concentrations. Recent developments in organic semiconductor materials have significantly enhanced device performance and stability. The integration of novel device architectures such as electrolyte-gated OFETs (EGOFETs) and extended-gate configurations has expanded the operational capabilities of these sensors in aqueous environments. Clinical applications span a broad spectrum of biomarkers, demonstrating the versatility of OFET biosensors in disease diagnosis and monitoring. Despite remarkable progress, challenges remain in terms of long-term stability, standardization, and translation to clinical practice. The convergence of organic electronics, biotechnology, and clinical medicine positions OFET biosensors as a promising platform for next-generation personalized healthcare and precision medicine applications. Full article

This work presents a catalysis-based electrochemical biosensor to evaluate the peroxidase-like activity of methemoglobin (Hb-PLA) after exposure to cigarette smoke (CS) at different time intervals. The system consists of a microelectrode array coupled with a PDMS chamber containing a methemoglobin solution (biorecognition element). Hydrogen peroxide (H₂O₂) acts as the substrate, while 3,3′,5,5′-tetramethylbenzidine (TMB) functions as the chromogenic substrate for the Hb-PLA through its oxidation reaction. A spectrophotometric technique is used as a reference method to assess the catalytic activity of methemoglobin. Positive control samples exhibited higher absorbance, indicating strong catalytic activity, whereas CS-exposed samples showed a marked reduction, which was confirmed by the negative control. Cyclic voltammetry revealed significant alterations in the oxidation and reduction peaks of the CS-exposed samples. Therefore, chronoamperometry was employed to quantify the charge transfer as the electrochemical response associated with Hb-PLA, yielding a sensitivity of 0.86 ± 0.06 (%Hb-PLA/mC) and a limit of detection (LOD) of 0.23 (mC). The results demonstrate that cigarette smoke impairs the Hb-PLA in a time-dependent manner, with longer exposure reducing the activity by up to 25%. The proposed biosensor provides a rapid, sensitive, and straightforward strategy for detecting functional alterations in solutions of methemoglobin induced by environmental pollutants such as cigarette smoke. Full article

Over the past two decades, the meat industry has faced increasing pressure to prevent foodborne outbreaks and reduce economic losses associated with delayed detection of spoilage. This demand has accelerated the development of on-site, real-time sensing tools capable of identifying early signs of contamination. Electrospun nanofiber (NF) platforms have emerged as particularly promising due to their large surface area, tunable porosity, and versatile chemistry, which make them ideal scaffolds for immobilizing enzymes, antibodies, or aptamers while preserving bioactivity under field conditions. These NFs have been integrated into optical, electrochemical, and resistive devices, each enhancing response time and sensitivity for key targets ranging from volatile organic compounds indicating early decay to specific bacterial markers and antibiotic residues. In practical applications, NF matrices enhance signal generation (SERS hotspots), facilitate analyte diffusion through three-dimensional networks, and stabilize delicate biorecognition elements for repeated use. This review summarizes major NF fabrication strategies, representative sensor designs for meat quality monitoring, and performance considerations relevant to industrial deployment, including reproducibility, shelf life, and regulatory compliance. The integration of such platforms with data networks and Internet of Things (IoT) nodes offers a path toward continuous, automated surveillance throughout processing and cold-chain logistics. By addressing current technical and regulatory challenges, NF-based biosensors have the potential to significantly reduce waste and safeguard public health through early detection of contamination before it escalates into costly recalls. Full article

Multiple-mode immunoassays have the advantages of self-correction, self-validation, and high accuracy and reliability. In this work, we developed a strategy for the design of triple-mode immunoassays with the self-assemblies of three-in-one small molecules as signal reporters. Pyrroloquinoline quinone (PQQ), with a well-defined redox peak and excellent spectroscopic and fluorescent signals, was chosen as the signaling molecule. PQQ was coordinated with Cu²⁺ to form metal–organic nanoparticle as the signal label. Hexahistidine (His₆)-tagged recognition element (recombinant streptavidin) was attached to the Cu-PQQ surface through metal coordination interaction between the His₆ tag and the unsaturated metal site. The captured Cu-PQQ nanoparticle released a large number of PQQ molecules under an acidic condition, which could be simultaneously monitoring by electrochemical, UV-vis, and fluorescent techniques, thereby allowing for the development of triple-model immunoassays. The three methods were used to determine the concentration of carcinoembryonic antigen (CEA) with the detection limits of 0.01, 0.1, and 0.1 ng/mL, respectively. This strategy opens up a universal route for the preparation of multiple-model signal labels and the oriented immobilization of bioreceptors for molecular recognition. Full article

Alanine aminotransferase (ALT) is a key biomarker of liver function. Compared with conventional assays for ALT detection—which are expensive, time-consuming, labor-intensive, and require experienced personnel—biosensors represent a promising alternative, but it remains unclear which biorecognitive enzymatic configuration offers the best analytical performance for ALT detection. This study presents the development and comparative evaluation of two amperometric biosensors based on oxidase biorecognition elements: pyruvate oxidase (POx) and glutamate oxidase (GlOx). Enzymes were immobilized onto platinum electrodes under optimized conditions using entrapment for POx (pH 7.4, enzyme loading 1.62 U/µL, PVA-SbQ concentration 13.2%) and covalent crosslinking for GlOx (pH 6.5, enzyme loading 2.67%, glutaraldehyde concentration 0.3%). Analytical parameters were systematically assessed, including linear range (1–500 U/L for POx vs. 5–500 U/L for GlOx), limit of detection (1 U/L for both), and sensitivity (0.75 vs. 0.49 nA/min at 100 U/L). The POx-based biosensor demonstrated higher sensitivity and lower detection limits, whereas the GlOx-based biosensor exhibited greater stability in complex solutions and reduced assay costs due to a simpler working solution. Moreover, while the POx-based system is uniquely suited for ALT determination, the GlOx-based sensor can be affected by AST activity in samples but may also be adapted for targeted AST detection. Overall, the study highlights a trade-off between sensitivity, robustness, and versatility in ALT biosensor design, providing guidance for the rational development of clinically relevant devices. Full article

Recent investigations into C-reactive protein (CRP) dynamics have shown that by evaluating the change in CRP level in a patient over time, it is possible to distinguish between bacterial and viral infections more accurately thereby guiding antimicrobial prescription practices. Consequently, a biosensor targeted towards CRP was developed using a nano- and microfiber mesh-based transducer. The produced transducers were functionalized with streptavidin, after which a biorecognition element, anti-CRP antibodies, could be bound to the sensor. Confirmation of the sensor production phases was obtained using fluorescence microscopy. The sensors were evaluated using Electrochemical Impedance Spectroscopy (EIS) and showed increasing changes in the impedance modulus corresponding to increasing concentrations of CRP in solution following a parabolic trend line. Full article

Optical biosensors have emerged as a transformative technology for food safety monitoring. These devices combine biorecognition molecules with advanced optical transducers, enabling the detection of a wide array of food contaminants, including pathogens, toxins, pesticides, and antibiotic residues. This review comprehensively explores the principles, advancements, applications, and future trends of optical biosensors in ensuring food safety. The key advantages of optical biosensors, such as high sensitivity to trace contaminants, fast response times, and portability, make them an attractive alternative to traditional analytical methods. Types of optical biosensors discussed include surface plasmon resonance (SPR), interferometric, fluorescence and chemiluminescence, and colorimetric biosensors. SPR biosensors stand out for their real-time, label-free analysis of foodborne pathogens and contaminants, while fluorescence and chemiluminescence biosensors offer exceptional sensitivity for detecting low levels of toxins. Interferometric and colorimetric biosensors, characterized by their portability and visual signal output, are well-suited for field-based applications. Biosensors have proven invaluable in monitoring heavy metals, pesticide residues, and antibiotic contaminants, ensuring compliance with stringent food safety standards. The integration of nanotechnology has further enhanced the performance of optical biosensors, with nanomaterials such as quantum dots and nanoparticles enabling ultra-sensitive detection and signal amplification. Optical biosensors represent a vital advancement in the field of food safety, addressing critical public health concerns through their rapid and reliable detection capabilities. Continued interdisciplinary efforts in nanotechnology, material science, and device engineering are poised to further expand their applications, making them indispensable tools for safeguarding global food supply chains. Full article

Self-assembly has emerged as a powerful bottom-up strategy for the construction of multifunctional nanocomposites based on upconversion nanoparticles (UCNPs). In contrast to epitaxial shell growth, self-assembly enables the modular integration of UCNPs with a broad spectrum of other functional nanomaterials. This characteristic makes it particularly attractive for various practical applications. This review provides a comprehensive overview of self-assembly methodologies for UCNP-based nanocomposites, including electrostatic interactions, hydrophobic interactions, covalent coupling, and specific biorecognition. The resultant nanohybrids exhibit a wide range of morphologies and functionalities, making them suitable for various applications, including multimodal imaging, bioimaging, advanced biosensing, smart nanocarriers for controlled molecular delivery, and orthogonal photoactivation for programmable therapy. Key recent studies are highlighted to elucidate the structure–function relationships and technological potential of these materials. Additionally, the current challenges, such as stability, reproducibility, and functional integration, and proposed future directions for the development of UCNP-based nanocomposites are further discussed. Full article

Considering the necessity of food safety testing, various biosensors have been developed based on biological elements (e.g., antibodies, aptamers), chemical elements (e.g., molecularly imprinted polymers), physical elements (e.g., nanopores) as recognition substances. According to the sensing patterns of signal transduction, the biosensors could be classified into optical and electrochemical biosensing, including fluorescence sensing, Raman sensing, colorimetric sensing, electrochemical sensing, etc. To enhance the sensing sensitivity, kinds of nanomaterials have been applied for signal amplification. With merits of high selectivity, sensitivity, and accuracy, the sensing strategies have been widely applied for food safety testing. This review highlights their signal output behavior, (e.g., fluorescence intensity shifts, Raman peak alterations, colorimetric changes, electrochemical current/voltage/impedance variations), nanostructure-mediated amplification mechanisms, and the fundamental recognition principles. Future efforts should prioritize multiplexed assay platforms, integration with microfluidics and smart devices, novel biorecognition elements, and sustainable manufacturing. Emerging synergies between biosensors and AI-driven data analytics promise intelligent monitoring systems for predictive food safety management, addressing challenges in food matrix compatibility and real-time hazard identification. Full article

The rapid rise of antibiotic-resistant bacteria (ABR) presents an urgent global health challenge, necessitating the development of efficient and scalable diagnostic technologies. Electrochemical biosensors have emerged as a promising solution, offering high sensitivity, specificity, and adaptability for point-of-care applications. These innovative platforms utilize bio-recognition elements, advanced electrode materials, microbial enzymes, and redox-active metabolites to identify antibiotic resistance profiles at a molecular level. Recent progress in microfluidics and lab-on-a-chip systems has enabled real-time, high-throughput antimicrobial susceptibility testing, significantly improving diagnostic precision and speed. This review aims to critically evaluate recent advances in electrochemical biosensing strategies for detecting ABR, identify key challenges, and propose future directions to enhance clinical applicability. Key developments include bio-receptor-based detection strategies, novel electrode surfaces, and multiplexed platforms integrated with microfluidic systems. Additionally, this review examines essential biomarkers for detecting antibiotic resistance and explores key challenges, including variability in biomarker expression and sensor reproducibility. It also highlights practical barriers to clinical implementation, such as cost constraints and scalability concerns. By presenting innovative approaches, such as cost-effective material alternatives, advanced analytical techniques, and portable biosensing systems, this review outlines a strategic pathway for enhancing the accessibility and effectiveness of electrochemical biosensors in antibiotic resistance management. Full article

Molecularly imprinted polymer nanoparticles (MIP NPs) are synthetic receptors with selective recognition sites for target molecules. They are employed instead of biorecognition elements in many applications due to their high affinity and selectivity, stability, easy preparation, and low cost. Their nanoscale size provides enhanced surface interactions, faster response times, improved biocompatibility, and effective cellular penetration, particularly in complex biological environments. MIP NPs provide high selectivity and structural versatility in the sample preparation, sensor-based detection, and controlled drug delivery, serving as promising alternatives to conventional methods. This review highlights the recent advancements in the synthesis and application of MIP NPs in three critical areas: sample preparation, sensor-based detection, and controlled drug release. Additionally, recent developments in green synthesis approaches, biocompatible materials, and surface functionalization strategies that are effective in the performance of MIP NPs are mentioned. Full article

Electrochemical biosensors are revolutionizing food testing by addressing critical limitations of conventional strategies that suffer from cost, complexity, and field-deployment challenges. Emerging fluorescence and Raman techniques, while promising, face intrinsic drawbacks like photobleaching and matrix interference in opaque or heterogeneous samples. In contrast, electrochemical biosensors leverage electrical signals to bypass optical constraints, enabling rapid, cost-effective, and pretreatment-free analysis of turbid food matrices. This review highlights their operational mechanisms, emphasizing nano-enhanced signal amplification (e.g., Au nanoparticles and graphene) and biorecognition elements (antibodies, aptamers, and molecularly imprinted polymers) for ultrasensitive assay of contaminants, additives, and adulterants. By integrating portability, scalability, and real-time capabilities, electrochemical biosensors align with global food safety regulations and sustainability goals. Challenges in standardization, multiplexed analysis, and long-term stability are discussed, alongside future directions toward AI-driven analytics, biodegradable sensors, and blockchain-enabled traceability, ultimately fostering precision-driven, next-generation food safety and quality testing. Full article