Characterization of Antibody Immobilization on Chitosan/Gelatin-Modified Electrode and Its Application to Bacillus cereus Detection in Cereal-Based Food

Nutritional optimization for bioprocess production of staphyloxanthin from Staphylococcus aureus with response surface methodology: promising anticancer scaffold targeting EGFR inhibition

BACKGROUND

Staphyloxanthin (STX) is a secondary metabolite pigment associated with membrane structures, recognized for its significant antioxidant properties. It plays a crucial role in combating reactive oxygen species (ROS), positioning it as a promising and effective alternative in cancer treatment. This study focused on enhancing the production of STX pigment by employing statistical optimization of media components, alongside the evaluation of its safety and anticancer properties.

RESULTS

A total of 59 Staphylococcus aureus isolates were screened and quantitatively estimated for STX production. The best pigment-producing isolate was identified based on molecular phylogenetic analysis as S. aureus A2, with accession number PP197164. A Box-Wilson central composite design was employed to evaluate the intricate interactions among six variables affecting the pigment yield. The most optimal conditions resulted in the highest production of STX of OD456 = 0.328, which is approximately 1.5-fold greater than the yield (OD456 = 0.215) obtained from OFAT optimization. The final response surface model fitting the data achieved a R² of 0.8748. STX exhibited marked cytotoxicity against the A549 NSCLC cell line with IC50 of 57.3 µg/mL, a safe dose in normal Vero cells. The anticancer activity of STX was predominantly mediated by the apoptotic pathway, as confirmed by confocal microscopy, the annexin V-FITC apoptosis assay, and the overexpression of caspase-3. Moreover, STX disrupted cell cycle at pre-G1 and G0/G1 phases in lung cancer. Intriguingly, STX exhibited its antitumor activity through reducing the EGFR expression. The molecular docking study revealed the potential binding interactions and affinities within the active sites of both wild-type and mutant EGFR.

CONCLUSION

The bioprocess for optimized production, combined with the biological profiling and low cytotoxicity, substantiates the potential application of STX pigment in combating lung cancer.

Electrochemical sensors: Types, applications, and the novel impacts of vibration and fluid flow for microfluidic integration

Electrochemical sensors are part of a diverse and evolving world of chemical sensors that are impacted by high demand and ongoing technological advancements. Electrochemical sensors offer benefits like cost-efficiency, short response time, ease of use, good limit of detection (LOD) and sensitivity, and ease of miniaturization while providing consistent analytical results. These sensors are employed in various fields-such as healthcare and diagnostics, environmental monitoring, and the food industry-to detect bacteria, viruses, heavy metals, pesticides, and more. In this review, we provide a comprehensive overview of electrochemical sensing techniques, with a focus on enhancing sensor performance through the integration of vibration and hydrodynamic flow in microfluidic systems. We present a structured comparison of these methods, utilizing tables to highlight the approaches most effective for performance enhancement. Additionally, we classify various electrochemical sensing applications, offering insights into the practical utilization of these two techniques for lowering the LOD. Finally, we present a comparative analysis of relevant studies, highlighting how hydrodynamic flow and vibration impact the sensing mechanism. We also explore the potential of these techniques to facilitate the development of automated, high-throughput microfluidic platforms, thereby optimizing their functionality and efficiency.

Advancing foodborne pathogen detection: a review of traditional and innovative optical and electrochemical biosensing approaches

Foodborne diseases are a significant cause of morbidity (600 million cases) and mortality (420,000 deaths) worldwide every year and are mainly associated with pathogens. Besides the direct effects on human health, they have relevant concerns related to financial, logistics, and infrastructure for the food and medical industries. The standard pathogen identification techniques usually require a sample enrichment step, plating, isolation, and biochemical tests. This process involves specific facilities, a long-time analysis procedures, and skilled personnel. Conversely, biosensors are an emerging innovative approach to detecting pathogens in real time due to their portability, specificity, sensitivity, and low fabrication costs. These advantages can be achieved from the synergistic work between nanotechnology, materials science, and biotechnology for coupling biomolecules in nano-matrices to enhance biosensing performance. This review highlights recent advancements in electrochemical and optical biosensing techniques for detecting bacteria and viruses. Key properties, such as detection limits, are examined, as they depend on factors like the design of the biorecognition molecule, the type of transducer, the target's characteristics, and matrix interferences. Sensitivity levels reported range from 1 to 1 × 10⁸ CFU/mL, with detection times spanning 10 min to 8 h. Additionally, the review explores innovative approaches, including biosensors capable of distinguishing between live and dead bacteria, multimodal sensing, and the simultaneous detection of multiple foodborne pathogens - emerging trends in biosensor development.

Electrochemical biosensors for pathogenic microorganisms detection based on recognition elements

The worldwide spread of pathogenic microorganisms poses a significant risk to human health. Electrochemical biosensors have emerged as dependable analytical tools for the point-of-care detection of pathogens and can effectively compensate for the limitations of conventional techniques. Real-time analysis, high throughput, portability, and rapidity make them pioneering tools for on-site detection of pathogens. Herein, this work comprehensively reviews the recent advances in electrochemical biosensors for pathogen detection, focusing on those based on the classification of recognition elements, and summarizes their principles, current challenges, and prospects. This review was conducted by a systematic search of PubMed and Web of Science databases to obtain relevant literature and construct a basic framework. A total of 171 publications were included after online screening and data extraction to obtain information of the research advances in electrochemical biosensors for pathogen detection. According to the findings, the research of electrochemical biosensors in pathogen detection has been increasing yearly in the past 3 years, which has a broad development prospect, but most of the biosensors have performance or economic limitations and are still in the primary stage. Therefore, significant research and funding are required to fuel the rapid development of electrochemical biosensors. The overview comprehensively evaluates the recent advances in different types of electrochemical biosensors utilized in pathogen detection, with a view to providing insights into future research directions in biosensors.

Recent Advances in Electrochemical Biosensors for Food Control

The rapid and sensitive detection of food contaminants is becoming increasingly important for timely prevention and treatment of foodborne disease. In this review, we discuss recent developments of electrochemical biosensors as facile, rapid, sensitive, and user-friendly analytical devices and their applications in food safety analysis, owing to the analytical characteristics of electrochemical detection and to advances in the design and production of bioreceptors (antibodies, DNA, aptamers, peptides, molecular imprinted polymers, enzymes, bacteriophages, etc.). They can offer a low limit of detection required for food contaminants such as allergens, pesticides, antibiotic traces, toxins, bacteria, etc. We provide an overview of a broad range of electrochemical biosensing designs and consider future opportunities for this technology in food control.

Electrospun Nanofibers including Organic/Inorganic Nanohybrids: Polystyrene- and Clay-Based Architectures in Immunosensor Preparation for Serum Amyloid A

Diagnostic techniques based on biomolecules have application potential that can be realized in many fields, such as disease diagnosis, bioprocess imaging, food/beverage industries, and environmental pollutant imaging. Successful surface immobilization of biomolecules is critical to increasing the stabilization, sensitivity, and selectivity of biomolecules used in bioassay systems. Nanofibers are good candidates for the immobilization of biomolecules owing to many advantages such as morphology and pore size. In this study, montmorillonite (MMT) clay is modified with poly(amidoamine) (PAMAM) generation 3 (PAMAM_G3) and added to polystyrene (PS) solutions, following which PS/MMT-PAMAM_G3 nanofibers are obtained using the electrospinning method. The nanofibers are obtained by testing PS% (wt%) and MMT-PAMAM_G3% (wt%) ratios and characterized with scanning electron microscopy. Antiserum amyloid A antibody (Anti-SAA) is then conjugated to the nanofibers on the electrode surface via covalent bonds using a zero-length cross linker. Finally, the obtained selective surface is used for electrochemical determination of serum amyloid A (SAA) levels. The linear range of PS/MMT-PAMAM/Anti-SAA is between 1 and 200 ng/mL SAA, and the detection limit is 0.57 ng/mL SAA. The applicability of PS/MMT-PAMAM_G3/Anti-SAA is investigated by taking measurements in synthetic saliva and serum both containing SAA.

Applications of Gelatin in Biosensors: Recent Trends and Progress

Gelatin is a natural protein from animal tissue with excellent biocompatibility, biodegradability, biosafety, low cost, and sol-gel property. By taking advantage of these properties, gelatin is considered to be an ideal component for the fabrication of biosensors. In recent years, biosensors with gelatin have been widely used for detecting various analytes, such as glucose, hydrogen peroxide, urea, amino acids, and pesticides, in the fields of medical diagnosis, food testing, and environmental monitoring. This perspective is an overview of the most recent trends and progress in the development of gelatin-based biosensors, which are classified by the function of gelatin as a matrix for immobilized biorecognition materials or as a biorecognition material for detecting target analytes.