sample containing E. coli and L. innocua served as proof-of-concept for the simultaneous detection-ID process. By performing a 204-minute sample-to-result AST, this technique also provides a proof-of-concept example of Rapid AST being superior to state-of-the-art methods. In principle the method uses an immunoassay platform to identify bacteria in samples without the need for culture enrichment. Horseradish peroxidase (HRP), a redox enzyme, is immobilized to the working electrode (WE) through a sandwich immune complex in the detecting platform. The gating voltage, VG, creates an electric field at the solution-enzyme-electrode interface, which lowers the electron tunnel barrier and improves the electrochemical signal between the electrode and HRP. As a function of VG, the signal current is amplified. The results show that the platform can provide a quantitative assessment of the susceptibilities of two strains of E. coli to ampicillin and chloramphenicol after two hours of antibiotic exposure. In the future, they hope to develop a test kit based on the platform described here, consisting of a set of detection electrodes individually immobilized with the antibody of one of the most common pathogens. The availability of specific antibodies is a potential weakness of this platform. According to a thorough search of antibody manufacturers, antibodies for the most encountered pathogens are already commercially available. The future development of this platform will necessitate extensive quality assurance of each antibody pair for a specific pathogen or strain. For each type of bacteria, a different working electrode needs to be constructed. The challenge in clinical viability of this technique is that it requires labelling antibodies on the surface of electrode, the exploration on various antibiotic panel needs to be explored along with clinical samples. Yi Liu and colleagues have demonstrated that electrochemical detection of pyocyanin (PYO), a redox-active bacterial metabolite secreted by Pseudomonas aeruginosa, can rapidly ascertain the critical ciprofloxacin level required for bactericidal deactivation, in as little as 2 hours in antibiotic-treated growth media. To improve detection sensitivity for PYO, nanoporous gold, modified with a self-assembled monolayer, is employed to mitigate interference from oxygen reduction while simultaneously maintaining a low charge transfer resistance level and preventing electrode fouling within biological sample matrices . Cristina Ocaña et. al,. have developed a simple, rapid, and cost-effective multichannel system for monitoring bacterial pH changes over time. The system employs miniaturized, all-solid-state pH sensors with a Ta2O5 sensitive layer to record pH changes resulting from bacterial growth in small volume Eppendorf test tubes. This approach is particularly valuable for evaluating microbial metabolic activity and antibiotic response. While blood pH can be assessed using electrodes or point-of-care instruments such as blood-gas analysers, these methods can be prohibitively expensive and complicated. The team successfully characterized the system using E. coli as a model bacterium and demonstrated its ability to detect increasing concentrations of viable E. coli in undiluted culture medium within just 5 hours of assay time, with a detection limit of less than 10 3 CFU/mL . Priyanka Mishra et. al. also implemented resazurin as a redox mediator to facilitate antibiotic susceptibility testing. Using the differential pulse voltammetry technique, electrochemical changes in peak current values were monitored, with interpretation based on these changes. Their findings reveal a novel approach that enables detection of 10^4 cells/mL in less than 4 hours for K. pneumoniae and E. coli, with results compared to gold standard AST. This methodology demonstrates promise for rapid AST and the use of a Pt-coated bio-electrode as a biosensor shows potential for analysing metabolic activity and monitoring the response of different antibiotics on bacterial cell viability. Another study reports the monitoring of riboflavin a redox protein secreted by the viable E. coli cells . In a study conducted by Benjamin Crane et. al., the utility of resazurin as redox mediators was explored for the detection of Escherichia coli with the goal of developing a diagnostic tool for urinary tract infection(Figure ). Notably, the study employed bulk modification of screen-printed electrodes during the carbon-graphitic ink screen printing process to incorporate resazurin into the electrodes. The detection sensitivity of resazurin was found to be as low as 15.6 μM via differential pulse voltammetry, in certain cases this strategy can alleviate the issue with mediators inferring with antibiotics. Conversely, the scholarly investigation conducted by Adam Bolotsky et. al., details the direct modification of screen-printed electrodes through the deposition of resazurin, thereby generating a crystalline formation(Figure ). This one-step approach enables the synthesis of a novel and exceptionally stable organic crystalline layer which exhibits redox activity. Furthermore, they have demonstrated the sensor as a reagent-free electrochemical sensor for in situ detection of bacterial metabolic activity with a response time of 60 min. Owing to its reagent-free nature, this methodology allows for direct measurement of bacterial activity, but it can be prone to certain inferring antibiotics. Furthermore, the work reported by Ritu Das et. al., presents an electrode modification technique is employed utilizing a facile alginate gel that has been impregnated with carbon nanodots(Figure ). The objective of this approach is to enable monitoring of bacterial growth kinetics as a function of pH., Many other techniques use similar strategies of electrode modification with multiwalled carbon nanotubes and graphene . In our group, R Pragadeeshwara Rao et al. proposed a variant of electrochemical antimicrobial susceptibility testing assay developed by Kamonnaree chotinantakul and peter Ertl that tracks changes in redox mediators in the presence of bacteria. The bacterial response (gram-negative E. coli and gram-positive B. subtilis) to various antibiotics is monitored using electrochemical measurement via cyclic voltammetry in the electrochemical antimicrobial susceptibility test (EAST). A bacterium has intrinsic redox properties that serve as a signature of its viability; this redox signature is used as a parameter for monitoring bacterial susceptibility using an electrochemical assay known as EAST. This method yields results for drug efficacy, half-life period, and IC50, among other things. Within 15 minutes of antibiotic incubation, whereas conventional methods require hours to days to see results. Also, this study suggests the changes in electrode kinetics with the use of nanomaterial could improve the performance of AST. In principle the method detects the redox behavior of E. coli and B. subtilis before and after undergoing antibiotic stress by monitoring changes in ferricyanide as redox mediators. To study the kinetics of bacterial response to various antibiotics, an electrochemical cell configuration with optimal concentrations of carbon nutrient and electron shuttle is developed (of various mechanisms of action). Increased sensitivity to EAST can be achieved by using a bacterial-friendly L-CeONP coated electrode, indicating that miniaturization will improve EAST efficacy. The author concluded that a bacteria-friendly L-CeONP-coated electrode could increase sensitivity toward EAST, implying that enhanced electron transportation rate (ETR) by the bacteria friendly semiconducting nano particles, would improve sensitivity toward EAST and hence would improve EAST efficacy. As for the clinical viability of the method, it can only interpret bactericidal activity, and clinical applicability requires the examination of a variety of clinical samples. The clinically viability solution is currently being developed as an extension of this work. Many studies are also devoted to the development of the sensor platform as the commercial instruments are expensive and they attempted to make a low cost potentiostat . Carine R. Nemr et. al have advanced an innovative approach to detecting methicillin-resistant Staphylococcus aureus (MRSA) in clinical samples such as nasal swabs. Their work involves utilizing an antibody-based capture probe, which can accurately report the endpoint of MRSA directly from these samples. This approach holds significant promise for clinical application, particularly as a primary antimicrobial susceptibility marker.