Search Results (18)

Ballast water (BW) is a major pathway for the spread of invasive microorganisms and pathogens, posing significant ecological and public health risks. The International Maritime Organization (IMO) has established strict discharge standards, yet routine monitoring remains limited, and no reliable onboard test is currently available to assist crews in verifying BW quality before discharge. This study presents the development of a rapid, portable method for onboard microbiological assessment of BW, based on potentiometric detection and biosensors engineered with the Bioelectric Recognition Assay (BERA). Two complementary approaches were evaluated: (i) direct potentiometric measurements of contaminated and non-contaminated samples, which confirmed the feasibility of detecting microbial presence but were restricted by high detection limits, and (ii) development of biosensors specifically engineered for Escherichia coli and Enterococcus spp. to improve specificity and lower the limit of detection (LOD). Results demonstrated successful detection of both microorganisms, with performance characteristics of 83.3% sensitivity and 81.9% accuracy for Enterococcus spp. (LOD: 10² CFU 100 mL⁻¹), and 89.8% sensitivity and 85.1% accuracy for Escherichia coli (LOD: 250 CFU 100 mL⁻¹). These findings underscore the potential of biosensor-based systems as practical, crew-operated tools for early warning and real-time monitoring of ballast water quality, supporting compliance with IMO standards and contributing to safer, more sustainable maritime operations. Full article

This study presents the proof-of-concept design and preliminary implementation of a bioelectric biosensor based on an Arduino platform for real-time monitoring of gel-immobilized N2a neuroblastoma cells using dopamine as a model neurotransmitter. The sensor operates on the principle of bioelectric recognition assay (BERA), and uses a two-electrode set-up as a simple, cost-efficient way to capture electrophysiological responses following dopamine exposure, while at the same time mimicking the in vivo cellular environment. Cellular ohmic resistance was assessed under increasing dopamine concentrations and temperatures (24 °C and 37 °C). The results showed that temperature significantly affected cell responses to increasing dopamine concentrations, possibly because of differences in dopamine diffusion in gel, which may in turn have affected membrane polarization and overall cell electric resistance. Pending further testing against a wider range of dopamine concentrations along with various dopamine agonists/antagonists, as well as optimization in terms of specificity, selectivity, and sensitivity, the biosensor could be applied in bioscreening and neuropharmacological studies in a user-friendly, scalable way. Full article

Prostate cancer is among the most prevalent malignancies in men worldwide, underscoring the need for early and accurate diagnostic tools. This study presents a proof-of-concept and pilot clinical validation of a novel bioelectric impedance-based biosensor for the detection of prostate-specific antigen (PSA) in human serum. The system integrates Molecular Identification through Membrane Engineering (MIME) with the xCELLigence real-time cell analysis platform, employing Vero cells electroinserted with anti-PSA antibodies. Optimization experiments identified 15,000 cells/well as the optimal configuration for impedance response. The biosensor exhibited specific, concentration-dependent changes in impedance upon exposure to PSA standard solutions and demonstrated significant differentiation between PSA-positive and PSA-negative human serum samples relative to the clinical threshold of 4 ng/mL. The biosensor offered rapid results within one minute, unlike standard immunoradiometric assay (IRMA), while showing strong diagnostic agreement. The system’s specificity, sensitivity, and reproducibility support its potential for integration into point-of-care screening workflows. This bioelectric assay represents one of the fastest PSA detection approaches reported to date and offers a promising solution for reducing overdiagnosis while improving clinical decision-making and patient outcomes. Full article

The prevalence of foodborne diseases is continuously increasing, causing numerous hospitalizations and deaths, as well as money loss in the agri-food sector and food supply chain worldwide. The standard analyses currently used for bacteria detection have significant limitations with the most important being their long procedural time that can be crucial for foodborne outbreaks. In this study, a biosensor system able to perform robust and accurate detection of Salmonella spp. in meat products was developed. To achieve this, a portable device developed by EMBIO Diagnostics called B.EL.D^TM (Bio Electric Diagnostics) and cell-based biosensor technology (BERA) were used. Results indicated that the new method could detect the pathogen within 24 h after a 3-min analysis and discriminate samples with and without Salmonella with high accuracy. Achieving an accuracy of 86.1% and a detection limit (LOD) of 1 log CFU g⁻¹, this innovative technology enables rapid and sensitive identification of Salmonella spp. in meat and meat products, making it an excellent tool for pathogen screening. Full article

Fungal plant pathogens have posed a significant threat to crop production. However, the large-scale application of pesticides is associated with possible risks for human health and the environment. Boscalid is a widely used fungicide, consistently implemented for the management of significant plant pathogens. Conventionally, the detection and determination of boscalid residues is based on chromatographic separations. In the present study, a Bioelectric Recognition Assay (BERA)-based experimental approach combined with MIME technology was used, where changes in the electric properties of the membrane-engineering cells with anti-boscalid antibodies were recorded in response to the presence of boscalid at different concentrations based on the maximum residue level (MRL) for lettuce. The membrane-engineering Vero cells with 0.5 μg/mL of antibody in their surface were selected as the best cell line in combination with the lowest antibody concentration. Furthermore, the biosensor was tested against another fungicide in order to prove its selectivity. Finally, the BERA cell-based biosensor was able to detect the boscalid residue, below and above the MRL, in spiked lettuce leaf extracts in an entirely distinct and reproducible manner. This study indicates that the BERA-based biosensor, after further development and optimization, could be used for the routine, high-throughput detection of boscalid residue in lettuce, and not only that. Full article

The prevalence of foodborne diseases is continuously increasing, causing numerous hospitalizations and deaths, as well as money loss in the agri-food sector and food supply chain worldwide. The standard analyses currently used for bacteria detection have significant limitations with the most important being their long procedural time that can be crucial for foodborne outbreaks. In this study, we developed a biosensor system able to perform robust and accurate detection of Salmonella spp. in meat products after a 3-min analysis. To achieve this, we used a portable device developed by EMBIO Diagnostics called B.EL.D (Bio Electric Diagnostics) and a cell-based biosensor technology (BERA). Results indicated that the new method could detect the pathogen within 24 h after a 3-min analysis and discriminate samples with and without Salmonella with high accuracy (86.1%). The method’s sensitivity, specificity, and positive and negative predictive values ranged from 80 to 90.5%, while the limit of detection was determined to be as low as 10 CFU g⁻¹ in all food substrates. Full article

As a consequence of the progress of the global vaccination against the COVID-19 disease, fast, accurate and affordable assays are needed for monitoring the efficiency of developing immunity against the coronavirus at the population level. In this context, we herewith report the proof-of-concept development of an innovative bioelectric biosensor for the ultra-detection (in less than three minutes) of IgG antibodies against the SARS-CoV-2 S1 spike antigen. The biosensor comprises a disposable set of screen-printed electrodes upon which are immobilized cells engineered to bear the S1 protein on their surface. When anti-S1 antibodies are presented to the engineered cell population, a rapid, specific, and selective change of the cell membrane potential occurs; this is in turn recorded by a bespoke portable potentiometer. End results are communicated via Bluetooth to a smartphone equipped with a customized user interface. By using the novel biosensor, anti-S1 antibodies could be detected at concentrations as low as 5 ng/mL. In a preliminary clinical trial, positive results were derived from patients vaccinated or previously infected by the virus. Selectivity over other respiratory viruses was demonstrated by the lack of cross-reactivity to antibodies against rhinovirus. After further clinical validation and extension to also screen IgM, IgA and possible neutralizing antibodies, our approach is intended to facilitate the mass and reliable detection of antibodies in the early stages following vaccination and to monitor the duration and level of acquired immunity both in a clinical and self-testing environment. Full article

Antigen screening for the SARS-CoV-2 S1 spike protein is among the most promising tools for the mass monitoring of asymptomatic carriers of the virus, especially in limited resource environments. Herewith, we report on the possible use of the angiotensin-converting enzyme 2 (ACE2), the natural receptor and entry point of the virus, as a biorecognition element for the detection of the S1 antigen combined with an established bioelectric biosensor based on membrane-engineered cells. The working principle of our approach is based on the measurable change of the electric potential of membrane-engineered mammalian cells bearing ACE2 after attachment of the respective viral protein. We demonstrate that sensitive and selective detection of the S1 antigen is feasible in just three min, with a limit of detection of 20 fg/mL. In a preliminary clinical application, positive patient-derived samples were identified with a 87.9% score compared to RT-PCR. No cross-reactivity was observed against a wide range of nucleocapsid protein concentrations. The novel biosensor is embedded in a commercially ready-to-use testing platform, complete with the consumable immobilized cell–electrode interface and a portable read-out device operable through smartphone or tablet. In addition, the possible application of the system for the high throughput screening of potential pharmacological inhibitors of the ACE2 receptor-S1 RBD interaction is discussed. Full article

The availability of antigen tests for SARS-CoV-2 represents a major step for the mass surveillance of the incidence of infection, especially regarding COVID-19 asymptomatic and/or early-stage patients. Recently, we reported the development of a Bioelectric Recognition Assay-based biosensor able to detect the SARS-CoV-2 S1 spike protein expressed on the surface of the virus in just three minutes, with high sensitivity and selectivity. The working principle was established by measuring the change of the electric potential of membrane-engineered mammalian cells bearing the human chimeric spike S1 antibody after attachment of the respective viral protein. In the present study, we applied the novel biosensor to patient-derived nasopharyngeal samples in a clinical set-up, with absolutely no sample pretreatment. More importantly, membrane-engineered cells were pre-immobilized in a proprietary biomatrix, thus enabling their long-term preservation prior to use as well as significantly increasing their ease-of-handle as test consumables. The plug-and-apply novel biosensor was able to detect the virus in positive samples with a 92.8% success rate compared to RT-PCR. No false negative results were recorded. These findings demonstrate the potential applicability of the biosensor for the early, routine mass screening of SARS-CoV-2 on a scale not yet realized. Full article

Human food-borne diseases caused by pathogenic bacteria have been significantly increased in the last few decades causing numerous deaths worldwide. The standard analyses used for their detection have significant limitations regarding cost, special facilities and equipment, highly trained staff, and a long procedural time that can be crucial for foodborne pathogens with high hospitalization and mortality rates, such as Listeria monocytogenes. This study aimed to develop a biosensor that could detect L. monocytogenes rapidly and robustly. For this purpose, a cell-based biosensor technology based on the Bioelectric Recognition Assay (BERA) and a portable device developed by EMBIO Diagnostics, called B.EL.D (Bio Electric Diagnostics), were used. Membrane engineering was performed by electroinsertion of Listeria monocytogenes homologous antibodies into the membrane of African green monkey kidney (Vero) cells. The newly developed biosensor was able to detect the pathogen’s presence rapidly (3 min) at concentrations as low as 10² CFU mL⁻¹, demonstrating a higher sensitivity than most existing biosensor-based methods. In addition, lack of cross-reactivity with other Listeria species, as well as with Escherichia coli, was shown, thus, indicating biosensor’s significant specificity against L. monocytogenes. Full article

Listeria monocytogenes is an intracellular bacterium that causes serious epidemic and sporadic food-borne illnesses in humans. Rapid and trustworthy methods are necessary for the detection of the pathogen to prevent potential food contamination. The aim of this study was to test a newly developed L. monocytogenes biosensor on actual food samples and validate its ability to detect the presence of pathogens robustly and accurately. The newly developed method uses a cell-based biosensor technology (BERA) and a portable device developed by EMBIO Diagnostics called B.EL.D, and provides results within 3 min. Tests were conducted on ready-to-eat lettuce salads, milk and halloumi cheese and the results indicate that the novel system was able to identify inoculated samples with 98%, 90%, and 91% accuracy, respectively. Furthermore, the limit of detection was determined to be as low as 0.6 log CFU mL⁻¹ or g⁻¹ in all food types. Classification of the samples Above or Below the detection limit was accessed through a newly developed algorithm for each food substrate. Samples were also analyzed with the ISO 11290-1:2017 and 11290-2:2017, in parallel. Thus, it was concluded that the newly developed biosensor can be a useful tool in the food supply chain, decreasing the required time for the detection of pathogens and increasing the number of tested samples before they reach the market. Full article

One of the key challenges of the recent COVID-19 pandemic is the ability to accurately estimate the number of infected individuals, particularly asymptomatic and/or early-stage patients. We herewith report the proof-of-concept development of a biosensor able to detect the SARS-CoV-2 S1 spike protein expressed on the surface of the virus. The biosensor is based on membrane-engineered mammalian cells bearing the human chimeric spike S1 antibody. We demonstrate that the attachment of the protein to the membrane-bound antibodies resulted in a selective and considerable change in the cellular bioelectric properties measured by means of a Bioelectric Recognition Assay. The novel biosensor provided results in an ultra-rapid manner (3 min), with a detection limit of 1 fg/mL and a semi-linear range of response between 10 fg and 1 μg/mL. In addition, no cross-reactivity was observed against the SARS-CoV-2 nucleocapsid protein. Furthermore, the biosensor was configured as a ready-to-use platform, including a portable read-out device operated via smartphone/tablet. In this way, we demonstrate that the novel biosensor can be potentially applied for the mass screening of SARS-CoV-2 surface antigens without prior sample processing, therefore offering a possible solution for the timely monitoring and eventual control of the global coronavirus pandemic. Full article

Population growth and increased production demands on fruit and vegetables have driven agricultural production to new heights. Nevertheless, agriculture remains one of the least optimized industries, with laboratory tests that take days to provide a clear result on the chemical level of produce. To address this problem, we developed a tailor-made solution for the industry that can allow multiple field tests on key pesticides, based on a bioelectric cell biosensor and the measurement of the cell membrane potential changes, according to the principle of the Bioelectric Recognition Assay (BERA). We developed a fully functional system that operates using a newly developed hardware for multiple data sources and an Android application to provide results within 3 min. The presence of acetamiprid residues caused a cell membrane hyperpolarization, which was distinguishable from the control samples. A database that classified samples Below or Above Maximum Residue Levels (MRL) was then created, based on a newly developed algorithm. Additionally, lettuce samples were analyzed with the conventional and the newly developed method, in parallel, revealing a high correlation on sample classification. Thus, it was demonstrated that the novel biosensor system could be used in the food supply chain to increase the number of tested products before they reach the market. Full article

This study presents a bioelectric cell-based biosensor for the monitoring of the pyrethroid pesticide cypermethrin, a voltage-gated sodium channel blocker, in tobacco samples. For this purpose, neuroblastoma cells were used as biorecognition elements. The potential interference by the tobacco major alkaloid nicotine on the detection of cypermethrin was also studied. In addition, fluorescence microscopy revealed a specific pattern of neuroblastoma cell calcium efflux (Ca²⁺) after treatment with nicotine or cypermethrin. Finally, actual field-derived tobacco extracts were used for assessing matrix effects on the biosensor’s performance. The biosensor could detect cypermethrin in concentrations up to 1.5 μg mL⁻¹ without being influenced by the presence of nicotine and possibly other tobacco alkaloids. Though not selective for cypermethrin, the neuroblastoma-based biosensor system appears to be a promising alternative to laborious analysis methodologies for rapid, high throughput and cost-efficient screening of this pyrethroid in tobacco samples in the near future. Full article

(1) Background: Fungal metabolites such as haloanisoles (especially 2,4,6-tribromoanisole/ 2,4,6-TCA) are contaminants of cork and wood barrels, materials that are widely used in the wine industry. Thus, the accurate and timely detection of these substances is very important for this sector of beverage industry. (2) Methods: Potentiometry was used for the Bioelectric Recognition Assay (BERA)-based experimental approach, where changes in the electric properties of the Vero cells modified with anti-TCA antibodies were recorded in response to the presence of 2,4,6-TCA in different concentrations. Furthermore, a second electrochemical biosensor system based on the cyclic voltammetric (CV) measurement of a reaction taking place on a screen printed electrode was developed in parallel to the customized application and configuration of the cell-based system. (3) Results: The BERA cell-based biosensor was able to quantitatively differentiate among the lower 2,4,6-TCA concentrations (control, 0.25 and 1.25 ng/L) from spiked oak barrel water extracts in an entirely distinct and reproducible manner. In contrast, the CV method was not sensitive enough to differentiate between the samples. (4) Conclusions: The present study indicates that the BERA-based biosensor after further development and optimization could be used for the routine, high throughput detection of 2,4,6-TCA in oak barrel water extracts. Full article