Roles of MXenes in biomedical applications: recent developments and prospects

Ta4C3 Nanosheets as a Novel Therapeutic Platform for Photothermal-Driven ROS Scavenging and Immune Activation against Antibiotic-Resistant Infections in Diabetic Wounds

The accumulation of excessive reactive oxygen species (ROS) and recurrent infections with drug-resistant bacteria pose significant challenges in diabetic wound infections, often leading to impediments in wound healing. Addressing this, there is a critical demand for novel strategies dedicated to treating and preventing diabetic wounds infected with drug-resistant bacteria. Herein, 2D tantalum carbide nanosheets (Ta4C3 NSs) have been synthesized through an efficient and straightforward approach, leading to the development of a new, effective nanoplatform endowed with notable photothermal properties, biosafety, and diverse ROS scavenging capabilities, alongside immunogenic attributes for diabetic wound treatment and prevention of recurrent drug-resistant bacterial infections. The Ta4C3 NSs exhibit remarkable photothermal performance, effectively eliminating methicillin-resistant Staphylococcus aureus (MRSA) and excessive ROS, thus promoting diabetic wound healing. Furthermore, Ta4C3 NSs enhance dendritic cell activation, further triggering T helper 1 (TH1)/TH2 immune responses, leading to pathogen-specific immune memory against recurrent MRSA infections. This nanoplatform, with its significant photothermal and immunomodulatory effects, holds vast potential in the treatment and prevention of drug-resistant bacterial infections in diabetic wounds.

Recent Advancement in Emerging MXene-Based Photocatalytic Membrane for Revolutionizing Wastewater Treatment

MXene-based photocatalytic membranes provide significant benefits for wastewater treatment by effectively combining membrane separation and photocatalytic degradation processes. MXene represents a pioneering 2D photocatalyst with a variable elemental composition, substantial surface area, abundant surface terminations, and exceptional photoelectric performance, offering significant advantages in producing high-performance photocatalytic membranes. In this review, an in-depth overview of the latest scientific progress in MXene-based photocatalytic membranes is provided. Initially, a brief introduction to the structure and photocatalytic capabilities of MXene is provided, highlighting their pivotal role in promoting the photocatalytic process. Subsequently, in pursuit of the optimal MXene-based photocatalytic membrane, critical factors such as the morphology, hydrophilicity, and stability of MXenes are meticulously taken into account. Various preparation strategies for MXene-based photocatalytic membranes, including blending, vacuum filtration, and dip coating, are also discussed. Furthermore, the application and mechanism of MXene-based photocatalytic membranes in micropollutant removal, oil-water separation, and antibacterial are examined. Lastly, the challenges in the development and practical application of MXene-based photocatalytic membranes, as well as their future research direction are delineated.

Staphylococcus aureus epidemiology, pathophysiology, clinical manifestations and application of nano-therapeutics as a promising approach to combat methicillin resistant Staphylococcus aureus

Staphylococcus aureus is a Gram-positive bacterium and one of the most prevalent infectious disease-related causes of morbidity and mortality in adults. This pathogen can trigger a broad spectrum of diseases, from sepsis and pneumonia to severe skin infections that can be fatal. In this review, we will provide an overview of S. aureus and discuss the extensive literature on epidemiology, transmission, genetic diversity, evolution and antibiotic resistance strains, particularly methicillin resistant S. aureus (MRSA). While many different virulence factors that S. aureus produces have been investigated as therapeutic targets, this review examines recent nanotechnology approaches, which employ materials with atomic or molecular dimensions and are being used to diagnose, treat, or eliminate the activity of S. aureus. Finally, having a deeper understanding and clearer grasp of the roles and contributions of S. aureus determinants, antibiotic resistance, and nanotechnology will aid us in developing anti-virulence strategies to combat the growing scarcity of effective antibiotics against S. aureus.

Control-Etched Ti3C2Tx MXene Nanosheets for a Low-Voltage-Operating Flexible Memristor for Efficient Neuromorphic Computation

Hardware neural networks with mechanical flexibility are promising next-generation computing systems for smart wearable electronics. Overcoming the challenge of developing a fully synaptic plastic network, we demonstrate a low-operating-voltage PET/ITO/p-MXene/Ag flexible memristor device by controlling the etching of aluminum metal ions in Ti3C2Tx MXene. The presence of a small fraction of Al ions in partially etched MXene (p-Ti3C2Tx) significantly suppresses the operating voltage to 1 V compared to 7 V from fully Al etched MXene (f-Ti3C2Tx)-based devices. Former devices exhibit excellent non-volatile data storage properties, with a robust ∼103 ON/OFF ratio, high endurance of ∼104 cycles, multilevel resistance states, and long data retention measured up to ∼106 s. High mechanical stability up to ∼73° bending angle and environmental robustness are confirmed with consistent switching characteristics under increasing temperature and humid conditions. Furthermore, a p-Ti3C2Tx MXene memristor is employed to mimic the biological synapse by measuring the learning-forgetting pattern for ∼104 cycles as potentiation and depression. Spike time-dependent plasticity (STDP) based on Hebb's Learning rules is also successfully demonstrated. Moreover, a remarkable accuracy of ∼95% in recognizing modified patterns from the National Institute of Standards and Technology (MNIST) data set with just 29 training epochs is achieved in simulation. Ultimately, our findings underscore the potential of MXene-based flexible memristor devices as versatile components for data storage and neuromorphic computing.

Multifunctional MXene-Based Platforms for Soft and Bone Tissue Regeneration and Engineering

MXenes and their composites hold great promise in the field of soft and bone tissue regeneration and engineering (TRE). However, there are challenges that need to be overcome, such as ensuring biocompatibility and controlling the morphologies of MXene-based scaffolds. The future prospects of MXenes in TRE include enhancing biocompatibility through surface modifications, developing multifunctional constructs, and conducting in vivo studies for clinical translation. The purpose of this perspective about MXenes and their composites in soft and bone TRE is to critically evaluate their potential applications and contributions in this field. This perspective aims to provide a comprehensive analysis of the challenges, advantages, limitations, and future prospects associated with the use of MXenes and their composites for soft and bone TRE. By examining the existing literature and research, the review seeks to consolidate the current knowledge and highlight the key findings and advancements in MXene-based TRE. It aims to contribute to the understanding of MXenes' role in promoting soft and bone TRE, addressing the challenges faced in terms of biocompatibility, morphology control, and tissue interactions.

Potential Biosafety of Mxenes: Stability, Biodegradability, Toxicity and Biocompatibility

MXenes are two-dimensional nanomaterials with unique properties that are widely used in various fields of research, mostly in the field of energy. Fewer publications are devoted to MXene application in biomedicine and the question is: are MXenes safe for use in biological systems? The sharp edges of MXenes provide the structure of "nanoknives" which cause damage in direct physical contact with cells. This is effectively used for antibacterial research. However, on the other hand, most studies in cultured cells and rodents report that they do not cause obvious signs of cytotoxicity and are fully biocompatible. The aim of our review was to consider whether MXenes can really be considered non-toxic and biocompatible. Often the last two concepts are confused. We first reviewed aspects such as the stability and biodegradation of MXenes, and then analyzed the mechanisms of toxicity and their consequences for bacteria, cultured cells, and rodents, with subsequent conclusions regarding their biocompatibility.

Polysaccharides as a promising platform for the treatment of spinal cord injury: A review

Spinal cord injury is incurable and often results in irreversible damage to motor function and autonomic sensory abilities. To enhance the effectiveness of therapeutic substances such as cells, growth factors, drugs, and nucleic acids for treating spinal cord injuries, as well as to reduce the toxic side effects of chemical reagents, polysaccharides have been gained attention due to their immunomodulatory properties and the biocompatibility and biodegradability of polysaccharide scaffolds. Polysaccharides hold potential as drug delivery systems in treating spinal cord injuries. This article aims to present an extensive evaluation of the potential applications of polysaccharide materials in scaffold construction, drug delivery, and immunomodulation over the past five years so that offering new directions and opportunities for the treatment of spinal cord injuries.

Engineering Photo-Cross-Linkable MXene-Based Hydrogels: Durable Conductive Biomaterials for Electroactive Tissues and Interfaces

Light-cured conductive hydrogels have attracted immense interest in the regeneration of electroactive tissues and bioelectronic interfaces. Despite the unique properties of MXene (MX), its light-blocking effect in the range of 300-600 nm hinders the efficient cross-linking of photocurable hydrogels. In this study, we investigated the photo-cross-linking process of MX-gelatin methacrylate (GelMa) composites with different types of photoinitiators and MX concentrations to prepare biocompatible, injectable, conductive, and photocurable composite hydrogels. The examined photoinitiators were Eosin Y, Irgacure 2959 (Type I), and lithium phenyl-2,4,6-trimethylbenzoyl phosphinate (Type II). The light-blocking effect of MX strongly affected the thickness, pore structure, swelling ratio, degradation, and mechanical properties of the light-cured hydrogels. Uniform distribution of MX in the hydrogel matrix was achieved at concentrations up to 0.04 wt % but the film thickness and curing times varied depending on the type of photoinitiator. It was feasible to prepare thin films (0.5 mm) by employing Type I photoinitiators under a relatively long light irradiation (4-5 min) while thick films with centimeter sizes could be rapidly cured by using Type II photoinitiator (<60 s). The mechanical properties, including elastic modulus, toughness, and stress to break for the Type II hydrogels were significantly superior (up to 300%) to those of Type I hydrogels depending on the MX concentration. The swelling ratio was also remarkably higher (648-1274%). A conductivity of about 1 mS/cm was attained at 0.1 mg/mL MX for the composite hydrogel cured by the Type I photoinitiator. In vitro cytocompatibility assays determined that the hydrogels promoted cell viability, metabolic activity, and robust proliferation of C2C12 myoblasts, which indicated their potential to support muscle cell growth during myogenesis. The developed photocurable GelMa-MX hydrogels have the potential to serve as bioactive and conductive scaffolds to modulate cellular functions and for tissue-device interfacing.

Post-Graphene 2D Materials: Structures, Properties, and Cancer Therapy Applications

Cancer is one of the most serious diseases challenging human health and life span. Cancer has claimed millions of lives worldwide. Early diagnosis and effective treatment of cancer are very important for the survival of patients. In recent years, 2D nanomaterials have shown great potential in the development of anticancer treatment by combining their inherent physicochemical properties after surface modification. 2D nanomaterials have attracted great interest due to their unique nanosheet structure, large surface area, and extraordinary physicochemical properties. This article reviews the advantages and application status of emerging 2D nanomaterials for targeted tumor synergistic therapy compared with traditional therapeutic strategies. In order to investigate novel potential anticancer strategies, this paper focuses on the surface modification, cargo delivery capability, and unique optical properties of emerging 2D nanomaterials. Finally, the current problems and challenges in cancer treatment are summarized and prospected.

MXene-based electrochemical devices applied for healthcare applications

The initial part of the review provides an extensive overview about MXenes as novel and exciting 2D nanomaterials describing their basic physico-chemical features, methods of their synthesis, and possible interfacial modifications and techniques, which could be applied to the characterization of MXenes. Unique physico-chemical parameters of MXenes make them attractive for many practical applications, which are shortly discussed. Use of MXenes for healthcare applications is a hot scientific discipline which is discussed in detail. The article focuses on determination of low molecular weight analytes (metabolites), high molecular weight analytes (DNA/RNA and proteins), or even cells, exosomes, and viruses detected using electrochemical sensors and biosensors. Separate chapters are provided to show the potential of MXene-based devices for determination of cancer biomarkers and as wearable sensors and biosensors for monitoring of a wide range of human activities.

In Situ Nanofiber Patch Boosts Postoperative Hepatocellular Carcinoma Immune Activation by Trimodal Combination Therapy

Poor clinical efficacy associated with postoperative hepatocellular carcinoma (HCC) often results from recurrence and metastasis. Hence, research has focused on establishing an effective multimodal therapy. However, complex combinations of active ingredients require multiple functions in therapeutic systems. Herein, a portable nanofiber patch composing germanium phosphorus (GeP) and anlotinib (AL) was designed to form a versatile platform for molecularly targeted photothermal-immune checkpoint blockade (ICB) trimodal combination therapy. The patches possess hydrophilic, satisfactory mechanical, and excellent photothermal conversion properties. Moreover, they achieve a penetrating and sustained drug release. The near-infrared light-assisted GeP-induced temperature increase regulates AL release, downregulating the expression of vascular-related factor receptors, triggering immunogenic cell death of tumor cells, and inducing dendritic cell maturation. Simultaneously, ICB therapy (programmed cell death ligand 1, PD-L1) was introduced to improve treatment outcomes. Notably, this trimodal combination therapy significantly inhibits vascular hypergrowth, enhances effector T-cell infiltration, and sensitizes the PD-L1 antibody response, boosting immunotherapy to suppress residual HCC recurrence and metastasis. Further validation of the genome sequencing results revealed cell pathways related primarily to regulatory immune effects. This study demonstrates the use of an effective and practical nanofiber patch to improve multimodal therapy of postoperative HCC, with high clinical translation value.

Preparation of branched polyethyleneimine-assisted boronic acid-functionalized magnetic MXene for the enrichment of catecholamines in urine samples

Herein, a magnetic borate-functionalized MXene composite with multiple boronic affinity sites was fabricated by embedding Fe3 O4 nanoparticles with 4-formylphenylboronic acid functionalized Ti3 C2 Tx nanosheets and served as sorbent for the simultaneous extraction of catecholamines (CAs) in urine samples. The morphology and structure of the magnetic materials were investigated using scanning microscopy, vibrating sample magnetometer, X-ray photoelectron spectrometer, and X-ray diffraction. The introduction of polyethyleneimine can amplify the bonded boronic acid groups, thereby effectively improving the adsorption capacities for CAs based on the multiple interactions of boronic affinity, hydrogen bonding, and metal coordination. The adsorption performance was investigated using the kinetics and isotherms models, and the main parameters that influence the extraction efficiency were optimized. Under the most favorable magnetic solid-phase extraction condition, a sensitive method for the analysis of CAs in urine samples was developed by combining magnetic solid-phase extraction conditions with high-performance liquid chromatography detection. The findings illustrated that the proposed approach possessed a wide linearity range of 0.05-250 ng/mL with an acceptable correlation coefficient (R2  ≥ 0.9984) and detection limits of 0.010-0.015 ng/mL for the target CAs. The research not only provides a notable composite with multiple boronic affinity sites but also offers an effective and feasible measure for the detection of CAs in biological samples.

3D-Printed Multifunctional Ag/CeO2/ZnO Reinforced Hydroxyapatite-Based Scaffolds with Effective Antibacterial and Mechanical Properties

Conventional three-dimensional (3D)-printed hydroxyapatite (HA)-based constructs have limited utility in bone tissue engineering due to their poor mechanical properties, elevated risk of microbial infection, and limited pore interconnectivity. 3D printing of complex multiple components to fabricate fully interconnected scaffolds is a challenging task; here, in this work, we have developed a procedure for fabrication of printable ink for complex systems containing multinanomaterials, i.e., HAACZ (containing 1 wt % Ag, 4 wt % CeO2, and 6 wt % ZnO) with better shear thinning and shape retention properties. Moreover, 3D-printed HAACZ scaffolds showed a modulus of 143.8 GPa, a hardness of 10.8 GPa, a porosity of 59.6%, effective antibacterial properties, and a fully interconnected pore network to be an ideal construct for bone healing. Macropores with an average size of ∼469 and ∼433 μm within the scaffolds of HA and HAACZ and micropores with an average size of ∼0.6 and ∼0.5 μm within the strut of HA and HAACZ were developed. The distribution of fully interconnected micropores was confirmed using computerized tomography, whereas the distribution of micropores within the strut was visualized using Voronoi tessellation. The water contact angle studies revealed the most suitable hydrophilic range of water contact angles of ∼71.7 and ∼76.6° for HA and HAACZ, respectively. HAACZ scaffolds showed comparable apatite formation and cytocompatibility as that of HA. Antibacterial studies revealed effective antibacterial properties for the HAACZ scaffold as compared to HA. There was a decrease in bacterial cell density for HAACZ from 1 × 105 to 1.2 × 103 cells/mm2 against Gram-negative (Escherichia coli) and from 1.9 × 105 to 5.6 × 103 bacterial cells/mm2 against Gram-positive (Staphylococcus aureus). Overall, the 3D-printed HAACZ scaffold resulted in mechanical properties, comparable to those of the cancellous bone, interconnected macro- and microporosities, and excellent antibacterial properties, which could be utilized for bone healing.

Thermally Conductive MXene

MXene materials, which consist of nitrides, carbides, or carbonitrides of transition metals, possess a distinctive multilayered structure resulting from the specific etching of the "A" layer from MAX phase precursors. This unique structure allows for tunable properties through intercalation and surface modification. Beyond their structural novelty, MXenes exhibit exceptional thermal conductivity, mechanical resilience, and versatile surface functionalization capabilities, rendering them highly versatile for a wide range of applications. They are particularly renowned for their multifaceted utility and are emerging as outstanding candidates in applications requiring robust thermal conductivity. MXenes, when integrated into textile, fiber, and film forms, have gained increasing relevance in fields where efficient heat management is essential. This work provides a comprehensive exploration of MXene materials, delving into their inherent structure and thermal properties. This Perspective places particular emphasis on their crucial role in efficient heat dissipation, which is vital for the development of wearable heaters and related technologies. Engineered compounds such as MXenes have become indispensable for personal and industrial heating applications, and the advancement of wearable electronic devices necessitates heaters with specific properties, including transparency, mechanical reliability, and adaptability. Recent advancements in emergent thermally conductive MXene compounds are discussed in this study, shedding light on their potential contributions across various domains, including wearable heaters and biosensors for healthcare and environmental monitoring. Furthermore, the versatile nature of MXene materials extends to their application in interfacial solar steam generation, representing a breakthrough approach for solar water desalination. This multifaceted utility underscores the vast potential of MXenes in addressing various pressing challenges.

MXene-Based Functional Platforms for Tumor Therapy

Recently, 2D transition metal carbide, nitride, and carbonitrides (MXenes) materials stand out in the field of tumor therapy, particularly in the construction of functional platforms for optimal antitumor therapy due to their high specific surface area, tunable performance, strong absorption of near-infrared light as well as preferable surface plasmon resonance effect. In this review, the progress of MXene-mediated antitumor therapy is summarized after appropriate modifications or integration procedures. The enhanced antitumor treatments directly performed by MXenes, the significant improving effect of MXenes on different antitumor therapies, as well as the MXene-mediated imaging-guided antitumor strategies are discussed in detail. Moreover, the existing challenges and future development directions of MXenes in tumor therapy are presented.

Current research status of tumor cell biomarker detection

With the annual increases in the morbidity and mortality rates of tumors, the use of biomarkers for early diagnosis and real-time monitoring of tumor cells is of great importance. Biomarkers used for tumor cell detection in body fluids include circulating tumor cells, nucleic acids, protein markers, and extracellular vesicles. Among them, circulating tumor cells, circulating tumor DNA, and exosomes have high potential for the prediction, diagnosis, and prognosis of tumor diseases due to the large amount of valuable information on tumor characteristics and evolution; in addition, in situ monitoring of telomerase and miRNA in living cells has been the topic of extensive research to understand tumor development in real time. Various techniques, such as enzyme-linked immunosorbent assays, immunoblotting, and mass spectrometry, have been widely used for the detection of these markers. Among them, the detection of tumor cell markers in body fluids based on electrochemical biosensors and fluorescence signal analysis is highly preferred because of its high sensitivity, rapid detection and portable operation. Herein, we summarize recent research progress in the detection of tumor cell biomarkers in body fluids using electrochemical and fluorescence biosensors, outline the current research status of in situ fluorescence monitoring and the analysis of tumor markers in living cells, and discuss the technical challenges for their practical clinical application to provide a reference for the development of new tumor marker detection methods.

M5X4: A Family of MXenes

MXenes are two-dimensional (2D) transition metal carbides, nitrides, and carbonitrides typically synthesized from layered MAX-phase precursors. With over 50 experimentally reported MXenes and a near-infinite number of possible chemistries, MXenes make up the fastest-growing family of 2D materials. They offer a wide range of properties, which can be altered by their chemistry (M, X) and the number of metal layers in the structure, ranging from two in M2XTx to five in M5X4Tx. Only one M5X4 MXene, Mo4VC4, has been reported. Herein, we report the synthesis and characterization of two M5AX4 mixed transition metal MAX phases, Ti2.5Ta2.5AlC4 and Ti2.675Nb2.325AlC4, and their successful topochemical transformation into Ti2.5Ta2.5C4Tx and Ti2.675Nb2.325C4Tx MXenes. The resulting MXenes were delaminated into single-layer flakes, analyzed structurally, and characterized for their thermal and optical properties. This establishes a family of M5AX4 MAX phases and their corresponding MXenes. These materials were experimentally produced based on guidance from theoretical predictions, leading to more exciting applications for MXenes.

MXene-Embedded Electrospun Polymeric Nanofibers for Biomedical Applications: Recent Advances

Recently MXenes has gained immense attention as a new and exciting class of two-dimensional material. Due to their unique layered microstructure, the presence of various functional groups at the surface, earth abundance, and attractive electrical, optical, and thermal properties, MXenes are considered promising candidates for various applications such as energy, environmental, and biomedical. The ease of dispersibility and metallic conductivity of MXene render them promising candidates for use as fillers in polymer nanocomposites. MXene-polymer nanocomposites simultaneously benefit from the attractive properties of MXenes and the flexibility and facile processability of polymers. However, the potentiality of MXene to modify the electrospun nanofibers has been less studied. Understanding the interactions between polymeric nanofibers and MXenes is important to widen their role in biomedical applications. This review explores diverse methods of MXene synthesis, discusses our current knowledge of the various biological characteristics of MXene, and the synthesis of MXene incorporated polymeric nanofibers and their utilization in biomedical applications. The information discussed in this review serves to guide the future development and application of MXene-polymer nanofibers in biomedical fields.

Advancements in pH-responsive nanocarriers: enhancing drug delivery for tumor therapy

INTRODUCTION

Tumors pose a significant global economic and health burden, with conventional cancer treatments lacking tumor specificity, leading to limited efficiency and undesirable side effects. Targeted tumor therapy is imminent. Tumor cells produce lactate and hydrogen ions (H+) by Warburg effect, forming an acidic tumor microenvironment (TME), which can be employed to design targeted tumor therapy. Recently, progress in nanotechnology has led to the development of pH-responsive nanocarriers, which have gathered significant attention. Under acidic tumor conditions, they exhibit targeted accumulation within tumor sites and controlled release profiles of therapeutic reagents, enabling precise tumor therapy.

AREAS COVERED

This review comprehensively summarize the principles underlying pH-responsive features, discussing various types of pH-responsive nanocarriers, their advantages, and limitations. Innovative therapeutic drugs are also examined, followed by an exploration of recent advancements in applying various pH-responsive nanocarriers as delivery systems for enhanced tumor therapy.

EXPERT OPINIONS

pH-responsive nanocarriers have garnered significant attention for their capability to achieve targeted accumulation of therapeutic agents at tumor sites and controlled drug delivery profiles, ultimately increasing the efficiency of tumor eradication. It is anticipated that the employment of pH-responsive nanocarriers will elevate the effectiveness and safety of tumor therapy, contributing to improved overall outcomes.

Biomedical application of 2D nanomaterials in neuroscience

Two-dimensional (2D) nanomaterials, such as graphene, black phosphorus and transition metal dichalcogenides, have attracted increasing attention in biology and biomedicine. Their high mechanical stiffness, excellent electrical conductivity, optical transparency, and biocompatibility have led to rapid advances. Neuroscience is a complex field with many challenges, such as nervous system is difficult to repair and regenerate, as well as the early diagnosis and treatment of neurological diseases are also challenged. This review mainly focuses on the application of 2D nanomaterials in neuroscience. Firstly, we introduced various types of 2D nanomaterials. Secondly, due to the repairment and regeneration of nerve is an important problem in the field of neuroscience, we summarized the studies of 2D nanomaterials applied in neural repairment and regeneration based on their unique physicochemical properties and excellent biocompatibility. We also discussed the potential of 2D nanomaterial-based synaptic devices to mimic connections among neurons in the human brain due to their low-power switching capabilities and high mobility of charge carriers. In addition, we also reviewed the potential clinical application of various 2D nanomaterials in diagnosing and treating neurodegenerative diseases, neurological system disorders, as well as glioma. Finally, we discussed the challenge and future directions of 2D nanomaterials in neuroscience.

Recent Advances in Two-Dimensional MXene-Based Electrochemical Biosensors for Sweat Analysis

Sweat, a biofluid secreted naturally from the eccrine glands of the human body, is rich in several electrolytes, metabolites, biomolecules, and even xenobiotics that enter the body through other means. Recent studies indicate a high correlation between the analytes' concentrations in the sweat and the blood, opening up sweat as a medium for disease diagnosis and other general health monitoring applications. However, low concentration of analytes in sweat is a significant limitation, requiring high-performing sensors for this application. Electrochemical sensors, due to their high sensitivity, low cost, and miniaturization, play a crucial role in realizing the potential of sweat as a key sensing medium. MXenes, recently developed anisotropic two-dimensional atomic-layered nanomaterials composed of early transition metal carbides or nitrides, are currently being explored as a material of choice for electrochemical sensors. Their large surface area, tunable electrical properties, excellent mechanical strength, good dispersibility, and biocompatibility make them attractive for bio-electrochemical sensing platforms. This review presents the recent progress made in MXene-based bio-electrochemical sensors such as wearable, implantable, and microfluidic sensors and their applications in disease diagnosis and developing point-of-care sensing platforms. Finally, the paper discusses the challenges and limitations of MXenes as a material of choice in bio-electrochemical sensors and future perspectives on this exciting material for sweat-sensing applications.