Ion-exchange Membranes Research Articles

Ion Exchange Membranes: Latest Developments toward High-Performance Vanadium Redox Flow Batteries

Ion Exchange Membranes: Latest Developments toward High-Performance Vanadium Redox Flow Batteries

Enrichment of lithium ions for battery application by electrolysis through a nanoporous membrane

In recent years, lithium (Li) has become a valuable commodity widely used in rechargeable batteries. The present study aims to extract battery-grade lithium-ion, as lithium hydroxide (LiOH), from lithium chloride (LiCl) solution by the membrane electrolysis process. Experiments are performed using a commercial cation exchange membrane and an indigenous High flux-Nanofiltration 300 alkali resistant (HF-NF 300 AR) nanoporous membrane. The dual-chamber electrolytic cell incorporates a selective membrane to separate the feed and concentrate chambers containing LiCl solution and deionized water. These two chambers are connected with titanium electrodes through the external circuit. The in-situ design of the compact two-chambered acrylic electrolytic cell helps to separate metal ions from ionizable salts of sodium, lithium, magnesium, potassium, etc. The experiment is conducted on a laboratory scale by varying the LiCl concentration at voltages of 24 V and 36 V. The feed and concentrate solutions are analyzed for pH, conductivity, and total dissolved solids. Inductively coupled plasma-optical emission spectrometry evaluates the presence of metal ions in the solution. The study shows effective metal ion recovery and separation to achieve battery-grade Li.

Ionomer and Membrane Designs for Low-temperature CO2 and CO Electrolysis.

Low-temperature electroreduction of CO2 and CO (CO(2)RR) into valuable chemicals and fuels offers a promising pathway to reduce greenhouse gas emissions and achieve carbon neutrality. Today's low-temperature CO(2)RR technology relies on the use of ionomers, polymers with ionized groups, primarily as catalyst layer (CL) additives. In the meantime, ionomers can assemble into ion-exchange membranes (IEMs), serving as important components of electrolyzers. According to the ion-exchange functions, ionomer additives are classified as cation-exchange ionomers (CEIs) and anion-exchange ionomers (AEIs); similarly, IEMs are divided into cation-exchange membranes (CEMs) and anion-exchange membranes (AEMs), as well as the multilayer polymer electrolytes (MPEs). Recent studies show that ionomer additives can regulate the catalytic microenvironment and thereby enhance performance towards desired products. This Review discusses the roles of ionomer additives and IEMs in CO2 and CO reduction reactions, highlighting the latest mechanistic insights and performance advances. It outlines challenges in designing ionomer additives and IEMs to improve product selectivity, energy efficiency (EE), and operational lifetime of CO(2)RR electrolyzers, while also providing perspectives on future research directions. The aim is to connect the current status of ionomer and membrane development with performance metrics analysis, offering insights for the advancement of commercially relevant low-temperature CO(2)RR electrolyzers.

Recovery of gold ions from thiosulfate solution using an electrogenerative process

Traditional zinc powder cementation method for recovering gold ions from thiosulfate solution has the disadvantages such as high consumption of active metal, surface passivation, and co-deposition of copper ions. The key to solving these issues is providing the necessary electrons for the reduction of Au(S2O3)23- while avoiding direct contact between zinc powder and the leaching solution. In this study, a novel electrogenerative device with ion exchange membranes separating the anode and cathode is developed for the recovery of gold ions from thiosulfate solution. The oxidation reaction of zinc electrode occurs in the anode chamber, while the reduction reaction of gold ions occurs on a platinum electrode in the cathode chamber. The optimal experimental conditions for the gold recovery are determined to be using a cation exchange membrane, with the anode solution of 0.08 M ZnSO4, pH = 6, and the cathode solution of 0.10 M Na2S2O3, 5 mM CuSO4, 0.5 M NH3·H2O, pH = 10, with an initial gold concentration of 10 mg/L. It obtains the gold recovery of 99.59 %. Compared the zinc powder cementation method with the similar gold recovery, the electrogenerative process reduces zinc consumption by 67 % and prevents the passivation on the zinc surface caused by copper, oxygen, and sulfur.

Alternate materials for the capture and quantification of gaseous oxidized mercury in the atmosphere

Abstract. Methodologies for identifying atmospheric oxidized mercury (HgII) compounds, including particulate-bound HgII (HgII(p)) and gaseous oxidized mercury (HgII(g)), by mass spectrometry are currently under development. This method requires preconcentration of HgII for analysis due to high instrument detection limits relative to ambient HgII concentrations. The objective of this work was to identify and test materials for quantitative capture of HgII from the gas phase and to suggest potential surfaces onto which HgII can be collected, thermally desorbed, and characterized using mass spectrometry methods. From the literature, several compounds were identified as potential sorbent materials and tested in the laboratory for uptake of gaseous elemental mercury (Hg0) and HgII(g) (permeated from a HgBr2 salt source). Chitosan, α-Al2O3, and γ-Al2O3 demonstrated HgII(g) capture in ambient air laboratory tests, without sorbing Hg0 under the same conditions. When compared to cation exchange membranes (CEMs), chitosan captured a comparable quantity of HgII(g), while ≤90 % of loaded HgII(g) was recovered from α-Al2O3 and γ-Al2O3. When deployed in the field, the capture efficiency of chitosan decreased compared to CEMs, indicating that environmental conditions impacted the sorption efficiency of this material. The poor recovery of HgII from the tested materials compared to CEMs in the field indicates that further identification and exploration of alternative sorbent materials are required to advance atmospheric mercury chemistry analysis by mass spectrometry methods.

Processing of Sludge Water from Alumina Production by Electrodialysis

The possibility of using the electrodialysis for processing weak aluminate solutions (sludge water) for the purpose of their concentration and causticization is analyzed. For testing, a three-chamber electro-dialysis cell with heterogeneous cation exchange membranes MK-40 was used. The optimal operating parameters of the process were determined, as follows: pole-to-pole distance 3–4 cm and current density 2 A/dm2 at the operating voltage on the cell of 20–26 V. Specific electricity consumption was established as 9.7–20.6 kWh/kg alkali, causticization efficiency 56.1–69.6%, alkali yield – 81%.

Ultra-Thin Cation Exchange Membranes: Sulfonated Polyamide Thin-Film Composite Membranes with High Charge Density

Ultra-Thin Cation Exchange Membranes: Sulfonated Polyamide Thin-Film Composite Membranes with High Charge Density

Effects of DOM and cations on the diffusion migration of PPCPs through ion exchange membranes

The transportation of pharmaceuticals and personal care products (PPCPs) in ion-exchange membranes was worrying, especially in complex substrates. Dissolved organic matter (DOM), the complexation of PPCPs and the membrane pollution formed by DOM were often confused in the existing studies. This paper investigated the diffusive migration patterns of three kinds of (PPCPs) through ion exchange membranes (IEMs) in complex substrates. Triclosan (TCS) exhibited the most probability of migration. Without considering the interference of environmental factors, more than 90 % of TCS was adsorbed by IEMs. The migration of sulfadiazine sodium (SD) and carbamazepine (CBZ) was less than 5 %. The DOM and cations altered the interaction of PPCPs and IEMs. DOM fouling on IEMs converted the direct strong binding of TCS to IEMs to indirect weak binding, and increased the transmembrane migration of TCS consequently. The presence of cations (Ca2+ and Mg2+) increased the inorganic binding of TCS to IEMs, and also promoted the transmembrane migration of TCS. However, coexisting of Mg2+ and humic acid (HA) decreased TCS migration through anion exchange membrane (AM), but increased TCS migration through cation exchange membrane (CM) due to the increasing of solution potential. The research provided a theoretical basis for exploring the safety of product solutions in IEMs systems.

The Role of Cation Exchange Membrane Characteristics in CO2 Electrolysis to CO Using Acid Anolyte

Cation exchange membranes are considered a suitable option for zero-gap CO2 electrolysis due to their potential to avoid carbonation and improve carbon efficiency. However, the use of acidic anolytes remains an issue due to high hydrogen production. This study investigates Nafion® membranes (111, 112, 115, 211, and 212) with different thicknesses produced by extrusion or solution-cast processes in a zero-gap cell with an acidic anolyte containing K2SO4. Faradaic efficiencies for CO production (FECO) are higher with thinner membranes, regardless of the manufacturing process, reaching FECO around 75% at 50 mA cm⁻². Additionally, membranes with similar thicknesses (∼50.8 µm) but produced in different ways displayed flow field carbonation after 3 hours of electrolysis at 30°C and 50 mA cm⁻². Linear sweep voltammetry (LSV) in full and half-cell configurations shows limiting diffusion current (iL) relative to proton transport for all the employed membranes, no matter the thickness. In contrast, the iL for Nafion® 115, the thicker membrane, is suppressed, indicating that proton depletion is fast and the electrode surface alkalinization primarily results from water reduction in this case. A mechanistic analysis was performed to explain the behavior of the limiting currents in the cell with Ar- and CO2-feed, indicating that CO2 reduction aids in the consumption of H+ provided by the membrane, increasing the local pH at less negative potentials. Overall, thinner membranes exhibited higher values of FECO and energy efficiency for CO (EE%CO). However, solution-cast membranes are more prone to provide K+, leading to better performance than those prepared by extrusion.

Screening of Cation Exchange Membranes for an Anthraquinone‐Ferrocyanide Flow Battery

AbstractThe disodium salt of 9,10‐anthraquinone‐2,7‐disulphonic acid (2,7‐AQDS) is an interesting platform for developing anthraquinone derivative negolytes for aqueous organic flow batteries. Recently, ammonium sulphate supporting electrolytes have been considered for improved stability and solubility. This work advances the 2,7‐AQDS/ferrocyanide flow battery with an ammonium sulphate supporting electrolyte (pH 5) by studying the suitability of six commercially available cation exchange membranes: E‐620, NR‐212, FS‐930, F‐1075‐PK, F‐1850 and N‐115. Cell cycling under galvanostatic regime plus potential hold was performed to determine coulombic efficiency, energy efficiency and accessible capacity for each membrane as well as capacity fade rate for three selected membranes under extended operation. Cell cycling under galvanostatic control only was carried out to observe transient membrane behavior alongside accessible capacity and apparent capacity fade rate. It was found that the capacity set by the limiting negolyte is consistent with 1.5 electrons per 2,7‐AQDS molecule and that energy efficiency shows a simple direct relationship to membrane thickness, with one exception. Meanwhile, four membranes displayed similar apparent capacity fade rates at this laboratory scale irrespective of their thickness, with capacity loss explained in terms of crossover. The best overall performance was attained by the thinnest membranes, E‐620 and NR‐212.

Production of Anthocyanin-Enriched Juices by Electrodialysis with Filtration Membrane Process: The Influence of Duration on Juice Composition, Process Efficiency, and Membrane Fouling.

The Electrodialysis with Filtration Membrane (EDFM) system has shown promise in juice enrichment, but further optimization is needed. This study evaluated the effect of processing duration (3 and 6 h) on juice composition, process efficiency, and membrane fouling. Results demonstrated a significant impact of processing time on juice composition, especially anthocyanin and mineral content. Two anthocyanin-depleted juices (-18.94% and -30.70%) and two anthocyanin-enriched juices (26.21% and 44.21%) were produced. Similar energy (1512.13 Wh/g of anthocyanins) was required to migrate equivalent amounts of anthocyanins over both time periods, with no impediment due to fouling observed, although the system's resistance increased (2.5-fold after 3 h, 3.2-fold after 6 h). Membrane fouling was characterized through conductivity, thickness, ATR-FTIR, SEM-EDX, and foulant identification. Minimal anthocyanin accumulation occurred on cation-exchange membranes (CEM), while anthocyanins and PACs concentrated within the filtering layer of filtration membranes (FM). However, fouling did not increase with longer processing. Structural alterations were noted in anion-exchange membranes (AEMs), suggesting instability under high electric fields. Overall, EDFM effectively enriched cranberry juice with anthocyanins, but further research is necessary to address AEM degradation under limiting current density conditions.

Toward circular greenhouse wastewater reuse: advancements in cation exchange membranes for selective Na+/K+ separation using electrodialysis systems

ABSTRACT Driven by the growing need for alternative water sources and forthcoming stringent nutrient discharge regulations, there is growing interest in developing selective membrane solutions to facilitate circular greenhouse wastewater reuse (as emphasized in the European Union's Horizon 2020 ULTIMATE project). For electrodialysis systems, sodium (Na+) over potassium (K+) selective membranes are essential to achieve minimal liquid discharge. This study addresses the challenge of developing selective, efficient, and scalable Na+/K+ cation exchange membranes. State-of-the-art cation exchange membrane developments were reviewed and the functionalization of commercial membranes with crown ethers was identified as a promising approach. Two crown ether–modified membranes (15-crown-5 (15C5) and 18-crown-6 (18C6)) were developed, characterized, and tested in equimolar and greenhouse wastewater binary feed ratios. While the results demonstrated low overall selectivity, the 15C5-modified membrane showed a marginal enhancement in K+ selectivity, suggesting the need for further optimization. The study concludes with recommendations for the future development of Na+/K+ selective membranes, highlighting the potential of machine learning approaches to expedite progress. This research provides a foundational step toward practical and scalable Na+/K+ ion separation solutions, for achieving minimal liquid discharge in greenhouse horticulture.

Theoretical Study of the Influence of Electroconvection on the Efficiency of Pulsed Electric Field (PEF) Modes in ED Desalination

Pulsed electric field (PEF) modes of electrodialysis (ED) are known for their efficiency in mitigating the fouling of ion-exchange membranes. Many authors have also reported the possibility of increasing the mass transfer/desalination rate and reducing energy costs. In the literature, such possibilities were theoretically studied using 1D modeling, which, however, did not consider the effect of electroconvection. In this paper, the analysis of the ED desalination characteristics of PEF modes is carried out based on a 2D mathematical model including the Nernst–Planck–Poisson and Navier–Stokes equations. Three PEF modes are considered: galvanodynamic (pulses of constant electric current alternate with zero current pauses), potentiodynamic (pulses of constant voltage alternate with zero voltage pauses), and mixed galvanopotentiodynamic (pulses of constant voltage alternate with zero current pauses) modes. It is found that at overlimiting currents, in accordance with previous papers, in the range of relatively low frequencies, the mass transfer rate increases and the energy consumption decreases with increasing frequency. However, in the range of high frequencies, the tendency changes to the opposite. Thus, the best characteristics are obtained at a frequency close to 1 Hz. At higher frequencies, the pulse duration is too short, and electroconvective vortices, enhancing mass transfer, do not have time to develop.

A low-impedance cation exchange membrane for extending the voltage window of a BiFeO3-based hybrid supercapacitor through the pH-decoupling strategy

Aqueous hybrid supercapacitors usually suffer from narrow voltage window and poor energy density limited by the thermodynamic decomposition of water. Based on necessary ion exchange membranes, the pH-decoupling strategy can be employed to extend the voltage windows of hybrid supercapacitors. We propose a novel low-impedance cation exchange membrane (CEM) with the interpenetrating network structure for the pH-decoupling strategy, which can be served as the separator for a AC//BiFeO3 supercapacitor to enhance its electrochemical performances. Two CEMs (CEM-1 and CEM-2) with different contents of the sulfonic acid (-SO3H) groups, are fabricated through the copolymerization of various monomers according to the predetermined stoichiometric ratios. FTIR, Raman and XPS spectra reflect that the CEM-2 has the higher content of the -SO3H groups than the CEM-1. The membrane parameter measurements confirm that the CEM-2 has the higher water content, lower membrane resistance and smaller membrane thickness than the CEM-1. The AC//BiFeO3 supercapacitor with the CEM-2 separator provides the higher gravimetric specific capacitance of 61 F g−1 at 1 A g−1, better coulombic efficiencies (97 % ∼ 103 %) and lower Rs value (39.74 Ω) than the AC//BiFeO3 supercapacitors with the CEM-1 separator. Moreover, the AC//BiFeO3 supercapacitor with the CEM-2 separator delivers the maximum energy density of 41.0 Wh kg−1 at the power density of 1.1 kW kg−1. The pH-decoupling strategy with this low-impedance CEM, opens up a new avenue for developing high-performance aqueous electrochemical energy storage devices.

Occurrence and efficient removal of PFAS from landfill leachates using on-site DTRO systems: A comprehensive analysis across 11 Chinese cities

Per- and polyfluoroalkyl substances (PFAS), known for their persistent toxicity and mobility, pose significant environmental and human health risks. Here we explored the occurrence and efficacy of on-site Double-Pass Reverse Osmosis (DTRO) systems in removing 30 different PFAS from landfill leachates in 11 diverse cities across China. PFAS concentrations in landfill leachate ranged from 938 to 32,491 ng/L, averaging 6,486 ng/L, predominantly comprising short-chain PFAS, notably perfluorobutane sulfonate (PFBS). Notable emerging substitutes like 6:2 fluorotelomer sulfonate, fluorobutane sulfonamide, and 9-chlorohexadecafluoro-3-oxanone sulfonate were also identified. The PFAS levels correlated positively (r2 = 0.79, p < 0.01) with regional economic development, with coastal areas exhibiting higher concentrations than inland regions. The DTRO membrane filtration and ion exchange resin achieved an average removal efficiency of 94 % for ∑30PFAS and even 99.97 % for PFBS (the concentration of PFBS in the raw leachate ranged from 226.36 ng/L to 27,935.61 ng/L, with an average concentration of 4,506.88 ng/L). The Na ion exchange resin had a limited effect on further reducing the PFAS concentration. Our findings not only contribute to the theoretical understanding of PFAS behavior in landfill leachates but also offer a practical engineering applications for global waste management practices.

Soft-hard zwitterionic additives for aqueous halide flow batteries.

Aqueous redox flow batteries with halide-based catholytes (where the halogen atom (X) is Br or I) are promising for sustainable grid energy storage. However, the formation of polyhalides during electrochemical charging and the associated phase separation into X2 limits the operable state of charge (SoC), results in vaporization and self-discharge inefficiencies, and spurs complete device failure1-3. Here we introduce soft-hard zwitterionic trappers (SH-ZITs) as complexing agents composed of a polyhalide-complexing 'soft' cationic motif and a water-soluble 'hard' anionic motif to enable homogeneous halide cycling. More than 300 structures were designed and 13 were characterized, showcasing the ability to complex polyhalides in homogeneous aqueous solution, to deter cation-exchange membrane crossover and to alter the electrochemical electrode mechanism. In flow battery cycling at a standard catholyte SoC of 66.6 per cent (stoichiometrically X3-), an average coulombic efficiency of more than 99.9 per cent at 40 milliamperes per square centimetre with no apparent decay was observed after more than 1,000 cycles over 2 months, with stability at elevated temperatures also demonstrated. Interestingly, SH-ZITs enable homogeneous cycling of the halide catholyte up to 90 per cent SoC at 2 moles per litre (47.7 ampere-hours per litre) for bromide, revealing previously unknown polyhalide regimes to be studied. Ultimately, SH-ZIT enables ultrahigh catholyte capacity utilization up to over 120 ampere-hours per litre at 80 per cent SoC with homogeneous cycling as well as the ability to pair with a zinc anode in a hybrid flow battery.

Insights into water insecurity in Indigenous communities in Canada: assessing microbial risks and innovative solutions, a multifaceted review.

Canada is considered a freshwater-rich country, despite this, several Indigenous reserves struggle with household water insecurity. In fact, some of these communities have lacked access to safe water for almost 30 years. Water quality in Canadian Indigenous reserves is influenced by several factors including source water quality, drinking water treatments applied, water distribution systems, and water storage tanks when piped water is unavailable. The objective of this multifaceted review is to spot the challenges and consequences of inadequate drinking water systems (DWS) and the available technical and microbiological alternatives to address water sanitation coverage in Indigenous reserves of Canada, North America (also known as Turtle Island). A comprehensive literature review was conducted using national web portals from both federal and provincial governments, as well as academic databases to identify the following topics: The status of water insecurity in Indigenous communities across Canada; Microbiological, chemical, and natural causes contributing to water insecurity; Limitations of applying urban-style drinking water systems in Indigenous reserves in Canada and the management of DWS for Indigenous communities in other high-income countries; and the importance of determining the microbiome inhabiting drinking water systems along with the cutting-edge technology available for its analysis. A total of 169 scientific articles matched the inclusion criteria. The major themes discussed include: The status of water insecurity and water advisories in Canada; the risks of pathogenic microorganisms (i.e., Escherichia coli and total coliforms) and other chemicals (i.e., disinfection by-products) found in water storage tanks; the most common technologies available for water treatment including coagulation, high- and low-pressure membrane filtration procedures, ozone, ion exchange, and biological ion exchange and their limitations when applying them in remote Indigenous communities. Furthermore, we reviewed the benefits and drawbacks that high throughput tools such as metagenomics (the study of genomes of microbial communities), culturomics (a high-efficiency culture approach), and microfluidics devices (microminiaturized instruments) and what they could represent for water monitoring in Indigenous reserves. This multifaceted review demonstrates that water insecurity in Canada is a reflection of the institutional structures of marginalization that persist in the country and other parts of Turtle Island. DWS on Indigenous reserves are in urgent need of upgrades. Source water protection, and drinking water monitoring plus a comprehensive design of culturally adapted, and sustainable water services are required. Collaborative efforts between First Nations authorities and federal, provincial, and territorial governments are imperative to ensure equitable access to safe drinking water in Indigenous reserves.

Deep learning-assisted prediction and profiled membrane microstructure inverse design for reverse electrodialysis

Compared to traditional inter-membrane spacers, profiled ion exchange membranes significantly improve the energy harvesting performance of reverse electrodialysis (RED). Here computational fluid dynamics is employed to generate data regarding the flow and mass transfer characteristics and performance index under different profiled membrane microstructures. Data-driven deep learning models are constructed for microstructure shape generation, physics field prediction, and performance forecasting. Results show that the microstructure shape generation via the Bezier generative adversarial network, the physical field prediction via conditional generative adversarial network for the velocity field and the performance prediction via multi-layer perceptron for power number and Sherwood number achieves satisfied accuracy, respectively. The gradient descent algorithm is utilized to optimize the microstructure shape achieving higher mass transfer performance and lower pump power consumption. Compared to the traditional straight ridge channel, the optimized microstructure channel exhibits a reduction of 18.85 % in the power number and an increase of 41.00 % in the Sherwood number, rendering significantly boosted performance.

Toward a Circular Lithium Economy with Electrodialysis: Upcycling Spent Battery Leachates with Selective and Bipolar Ion-Exchange Membranes.

Recycling spent lithium-ion batteries offers a sustainable solution to reduce ecological degradation from mining and mitigate raw material shortages and price volatility. This study investigates using electrodialysis with selective and bipolar ion-exchange membranes to establish a circular economy for lithium-ion batteries. An experimental data set of over 1700 ion concentration measurements across five current densities, two solution compositions, and three pH levels supports the techno-economic analysis. Selective electrodialysis (SED) isolates lithium ions from battery leachates, yielding a 99% Li-pure retentate with 68.8% lithium retention, achieving relative ionic fluxes up to 2.41 for Li+ over transition metal cations and a selectivity of 5.64 over monovalent cations. Bipolar membrane electrodialysis (BMED) converts LiCl into high-purity LiOH and HCl, essential for battery remanufacturing and reducing acid consumption via acid recycling. High current densities reduce ion leakage, achieving lithium leakage as low as 0.03%, though hydronium and hydroxide leakage in BMED remains high at 11-20%. Our analysis projects LiOH production costs between USD 1.1 and 3.6 per kilogram, significantly lower than current prices. Optimal SED and BMED conditions are identified, emphasizing the need to control proton transport in BMED and improve cobalt-lithium separation in SED to enhance cost efficiency.

Towards real-time myocardial infarction diagnosis: a convergence of machine learning and ion-exchange membrane technologies leveraging miRNA signatures.

Rapid diagnosis of acute myocardial infarction (AMI) is crucial for optimal patient management. Accurate diagnosis and time of onset of an acute event can influence treatment plans, such as percutaneous coronary intervention (PCI). PCI is most beneficial within 3 hours of AMI onset. MicroRNAs (miRNAs) are promising biomarkers, with potential of early AMI diagnosis, since they are released before cell death and subsequent release of larger molecules [e.g., cardiac troponins (cTn)], and have greater sensitivity and stability in plasma versus cTn regardless of timing of AMI onset. However, miRNA-based AMI diagnosis can result in false positives due to miRNA content overlap between AMI and stable coronary artery disease (CAD). Accordingly, we explored the possibility of using a miRNA profile, rather than a single miRNA, to distinguish between CAD and AMI, as well as different stages following AMI onset. First we screened a library of 800 miRNA using plasma samples from 4 patient cohorts; no known CAD, CAD, ST-segment elevation myocardial infarction (STEMI) and STEMI followed by PCI, using Nanostring miRNA profiling technology. From this screening, based on machine learning SCAD and Lasso algorithms, we identified 9 biomarkers (miR-200b, miR-543, miR-331, miR-3605, miR-301a, miR-18a, miR-423, miR-142, and miR-132) that were differentially expressed in CAD, STEMI and STEMI-PCI and explored them to identify a miRNA profile for rapid and accurate AMI diagnosis. These 9 miRNAs were selected as the most frequently identified targets by SCAD and Lasso, as indicated in the "drum-plot" model in the machine learning approach. We used age-matched patient samples to validate selected 9 miRNA biomarkers using a multiplexed ion-exchange membrane-based miRNA sensor platform, which measures specific miRNAs, and cTn as a control, simultaneously as a point-of-care device. Findings from this study will inform timely and accurate diagnosis of AMI and its stages, which are essential for effective management and optimal patient outcomes.