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a) Low-, b) high-magnification TEM, and c) high-resolution TEM images of Zn-MOF@Ti 3 C 2 T x . d) TEM elemental mappings and e) EDX spectra of the Zn-MOF@Ti 3 C 2 T x hybrid: C (red), N (green), O (yellow), Ti (orange), and Zn (blue). f ) N 2 adsorption/desorption isotherms at 77 K, and g) XRD patterns of i) Zn-MOF, ii) Ti 3 C 2 T x , and iii) Zn-MOF@Ti 3 C 2 T x . h) High-resolution Zn 2p XPS spectra of i) Zn-MOF and ii) Zn-MOF@Ti 3 C 2 T x . i) High-resolution Ti 2p XPS spectra of i) Ti 3 C 2 T x and ii) Zn-MOF@Ti 3 C 2 T x . j) EPR spectra of i) Zn-MOF and ii) Zn-MOF@Ti 3 C 2 T x .
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A novel multimodal antibacterial platform is constructed by the in situ growth of a bioactive zinc‐based metal–organic framework (Zn‐MOF) using the natural antibacterial agent (curcumin) as ligand over the Ti3C2Tx nanosheets (NSs) for highly effective bacteria‐infected wound healing. As Zn nodes in Zn‐MOF can be partially exchanged by Ti sites in T...
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... field-emission scanning electron microscopy (FESEM) image of Zn-MOF ( Figure S1a, Supporting Information) shows that it has an accordion-like shape and comprises multilayered sheets but with diverse nanosizes. The transmission electron microscopy (TEM) images of Zn-MOF ( Figure S1b,c, Supporting Information) further prove its layered structure. ...
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... field-emission scanning electron microscopy (FESEM) image of Zn-MOF ( Figure S1a, Supporting Information) shows that it has an accordion-like shape and comprises multilayered sheets but with diverse nanosizes. The transmission electron microscopy (TEM) images of Zn-MOF ( Figure S1b,c, Supporting Information) further prove its layered structure. The corresponding energy-dispersive X-ray (EDX) mapping image of Zn-MOF ( Figure S1d, Supporting Information) clearly shows the homogenous distribution of C, N, O, and Zn elements. ...
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... transmission electron microscopy (TEM) images of Zn-MOF ( Figure S1b,c, Supporting Information) further prove its layered structure. The corresponding energy-dispersive X-ray (EDX) mapping image of Zn-MOF ( Figure S1d, Supporting Information) clearly shows the homogenous distribution of C, N, O, and Zn elements. In addition, the SEM image of Ti 3 C 2 T x NSs ( Figure S1e, Supporting Information) reveals a nanoflake-like shape, which was further proven by the TEM image ( Figure S1f, Supporting Information). ...
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... corresponding energy-dispersive X-ray (EDX) mapping image of Zn-MOF ( Figure S1d, Supporting Information) clearly shows the homogenous distribution of C, N, O, and Zn elements. In addition, the SEM image of Ti 3 C 2 T x NSs ( Figure S1e, Supporting Information) reveals a nanoflake-like shape, which was further proven by the TEM image ( Figure S1f, Supporting Information). Clearly, Ti 3 C 2 T x is composed of large amounts of NSs, and the high-resolution TEM (HRTEM) image ( Figure S1g, Supporting Information) shows that the interlayer spacing of 0.24 nm agrees well with the (103) plane of Ti 3 C 2 T x NSs. ...
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... corresponding energy-dispersive X-ray (EDX) mapping image of Zn-MOF ( Figure S1d, Supporting Information) clearly shows the homogenous distribution of C, N, O, and Zn elements. In addition, the SEM image of Ti 3 C 2 T x NSs ( Figure S1e, Supporting Information) reveals a nanoflake-like shape, which was further proven by the TEM image ( Figure S1f, Supporting Information). Clearly, Ti 3 C 2 T x is composed of large amounts of NSs, and the high-resolution TEM (HRTEM) image ( Figure S1g, Supporting Information) shows that the interlayer spacing of 0.24 nm agrees well with the (103) plane of Ti 3 C 2 T x NSs. ...
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... addition, the SEM image of Ti 3 C 2 T x NSs ( Figure S1e, Supporting Information) reveals a nanoflake-like shape, which was further proven by the TEM image ( Figure S1f, Supporting Information). Clearly, Ti 3 C 2 T x is composed of large amounts of NSs, and the high-resolution TEM (HRTEM) image ( Figure S1g, Supporting Information) shows that the interlayer spacing of 0.24 nm agrees well with the (103) plane of Ti 3 C 2 T x NSs. [35] After the hybridization of Zn-MOF and Ti 3 C 2 T x NSs, the accordion-like structure of Zn-MOF is well maintained and anchored on the surface of Ti 3 C 2 T x NSs ( Figure S2, Supporting Information). ...
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... means that the introduction of Ti 3 C 2 T x NSs would not affect the formation of Zn-MOF. Moreover, the close interconnection between Zn-MOF and Ti 3 C 2 T x is confirmed by TEM images (Figure 1a,b). In the HRTEM image (Figure 1c), a lattice spacing of 0.22 nm can be found, which is attributed to the (014) plane of Ti 5.73 C 3.72 (JCPDS 77-1089). ...
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... the close interconnection between Zn-MOF and Ti 3 C 2 T x is confirmed by TEM images (Figure 1a,b). In the HRTEM image (Figure 1c), a lattice spacing of 0.22 nm can be found, which is attributed to the (014) plane of Ti 5.73 C 3.72 (JCPDS 77-1089). [36] The elemental mapping image of Zn-MOF@Ti 3 C 2 T x (Figure 1d) further illustrates that Ti element can only be observed within the Ti 3 C 2 T x part, whereas Zn element appears in the Zn-MOF part. ...
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... the HRTEM image (Figure 1c), a lattice spacing of 0.22 nm can be found, which is attributed to the (014) plane of Ti 5.73 C 3.72 (JCPDS 77-1089). [36] The elemental mapping image of Zn-MOF@Ti 3 C 2 T x (Figure 1d) further illustrates that Ti element can only be observed within the Ti 3 C 2 T x part, whereas Zn element appears in the Zn-MOF part. Further, C and O elements can be found in the whole selected region. ...
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... C and O elements can be found in the whole selected region. The EDX result shows that the atomic percentages of Zn, Ti, C, N, and O are 6.64%, 23.59%, 56.40%, 1.66%, and 11.71%, respectively (Figure 1e), further verifying the successful combination of Zn-MOF and Ti 3 C 2 T x NSs. The N 2 adsorption-desorption isotherm of Zn-MOF (curve i, Figure 1f ) exhibits a large BrunauerEmmett-Teller (BET) specific surface area of 1994.7 m 2 g À1 , accompanied with a narrow pore size distribution centered at 7.4 Å ( Figure S3, Supporting Information). ...
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... EDX result shows that the atomic percentages of Zn, Ti, C, N, and O are 6.64%, 23.59%, 56.40%, 1.66%, and 11.71%, respectively (Figure 1e), further verifying the successful combination of Zn-MOF and Ti 3 C 2 T x NSs. The N 2 adsorption-desorption isotherm of Zn-MOF (curve i, Figure 1f ) exhibits a large BrunauerEmmett-Teller (BET) specific surface area of 1994.7 m 2 g À1 , accompanied with a narrow pore size distribution centered at 7.4 Å ( Figure S3, Supporting Information). Moreover, Ti 3 C 2 T x (curve ii, Figure 1f ) has a relatively small surface area of 30.05 m 2 g À1 . ...
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... N 2 adsorption-desorption isotherm of Zn-MOF (curve i, Figure 1f ) exhibits a large BrunauerEmmett-Teller (BET) specific surface area of 1994.7 m 2 g À1 , accompanied with a narrow pore size distribution centered at 7.4 Å ( Figure S3, Supporting Information). Moreover, Ti 3 C 2 T x (curve ii, Figure 1f ) has a relatively small surface area of 30.05 m 2 g À1 . As compared, Zn-MOF@Ti 3 C 2 T x (curve iii, Figure 1f ) exhibits a slight smaller surface area (1928.7 m 2 g À1 ) than that of Zn-MOF, due to the combination of Zn-MOF and Ti 3 C 2 T x NSs. ...
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... Ti 3 C 2 T x (curve ii, Figure 1f ) has a relatively small surface area of 30.05 m 2 g À1 . As compared, Zn-MOF@Ti 3 C 2 T x (curve iii, Figure 1f ) exhibits a slight smaller surface area (1928.7 m 2 g À1 ) than that of Zn-MOF, due to the combination of Zn-MOF and Ti 3 C 2 T x NSs. ...
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... powder X-ray diffraction (PXRD) pattern of Zn-MOF (curve i, Figure 1g) resembles previous work. [34] The XRD pattern of Ti 3 C 2 T x NSs (curve ii, Figure 1g) shows a strong peak at 2θ ¼ 6.66°, which corresponds to the (002) plane. ...
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... powder X-ray diffraction (PXRD) pattern of Zn-MOF (curve i, Figure 1g) resembles previous work. [34] The XRD pattern of Ti 3 C 2 T x NSs (curve ii, Figure 1g) shows a strong peak at 2θ ¼ 6.66°, which corresponds to the (002) plane. [37] Furthermore, the PXRD pattern of Zn-MOF@Ti 3 C 2 T x (curve iii, Figure 1g) depicts the characteristic diffraction peaks of both Zn-MOF and Ti 3 C 2 T x , revealing the successful integration. ...
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... The XRD pattern of Ti 3 C 2 T x NSs (curve ii, Figure 1g) shows a strong peak at 2θ ¼ 6.66°, which corresponds to the (002) plane. [37] Furthermore, the PXRD pattern of Zn-MOF@Ti 3 C 2 T x (curve iii, Figure 1g) depicts the characteristic diffraction peaks of both Zn-MOF and Ti 3 C 2 T x , revealing the successful integration. However, the (002) peak ascribed to Ti 3 C 2 T x MXene in the Zn-MOF@Ti 3 C 2 T x hybrid shifts to a lower position of 5.9° and tends to be sharp. ...
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... anticipated, Zn 2p and Ti 2p signals are found in Zn-MOF@Ti 3 C 2 T x (curve iii, Figure S6, Supporting Information) apart from C, N, and O signals. As for the high-resolution Zn 2p XPS spectra of Zn-MOF and Zn-MOF@Ti 3 C 2 T x (Figure 1h), two clear peaks at the binding energies (BEs) of 1021.7 and 1044.8 eV appear, which are due to Zn 2p 3/2 and Zn 2p 1/2 , respectively. The BEs of Zn 2p 3/2 and Zn 2p 1/2 for Scheme 1. Schematic illustration of the synthetic process for Zn-MOF@Ti 3 C 2 T x hybrid and the use of Zn-MOF@Ti 3 C 2 T x for multimodal antibacterial study and wound healing. ...
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... would result in the structure defects at the Zn-MOF network edges. [39] The high-resolution Ti 2p XPS spectrum of Ti 3 C 2 T x (Figure 1i) NSs were possibly oxidized during the preparation procedure of Zn-MOF@Ti 3 C 2 T x . As reported, the oxygen-related functional groups such as -OH and -O groups can be reserved on the Ti 3 C 2 T x surface. ...
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... results indicate the successful preparation of Zn-MOF@Ti 3 C 2 T x hybrid. Further, the electron paramagnetic resonance (EPR) spectra of Zn-MOF and Zn-MOF@Ti 3 C 2 T x were measured to confirm the existence of OVs (Figure 1j). Both Zn-MOF and Zn-MOF@Ti 3 C 2 T x demonstrate obvious signal at about g ¼ 1.998, which is ascribed to OVs of the bound single electron. ...
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... deeply understand the antibacterial mechanism of the developed Zn-MOF@Ti 3 C 2 T x Schottky junction, the photodynamic effects of the Zn-MOF and Ti 3 C 2 T x mixture (represented by Zn-MOF/Ti 3 C 2 T x ) were also measured using the same way. As depicted in Figure S13a, Supporting Information, no substantial change can be observed in the absorption intensity of DPBF for Zn-MOF/Ti 3 C 2 T x in the dark, suggesting the absence of 1 O 2 species. Figure S13b, Supporting Information, shows the slowly gradual decline of the absorption intensity under NIR light irradiation (1.0 W cm À2 , 15 min). ...
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... depicted in Figure S13a, Supporting Information, no substantial change can be observed in the absorption intensity of DPBF for Zn-MOF/Ti 3 C 2 T x in the dark, suggesting the absence of 1 O 2 species. Figure S13b, Supporting Information, shows the slowly gradual decline of the absorption intensity under NIR light irradiation (1.0 W cm À2 , 15 min). This finding reveals that a certain content of 1 O 2 species can be generated, which may be attributed to the effect of Ti 3 C 2 T x . ...
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... to the negligible absorption of Zn-MOF in NIR region, only a slight temperature increase was achieved (34.9 °C). In contrast, the temperature of Ti 3 C 2 T x NSs (100 μg mL À1 ) ( Figure S11, Supporting Information) reaches up to 71.3 °C after NIR laser irradiation for 15 min owing to the excellent photothermal conversion ability of Ti 3 C 2 T x (90.1%) ( Figure S12, Supporting Information). ...
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... to the negligible absorption of Zn-MOF in NIR region, only a slight temperature increase was achieved (34.9 °C). In contrast, the temperature of Ti 3 C 2 T x NSs (100 μg mL À1 ) ( Figure S11, Supporting Information) reaches up to 71.3 °C after NIR laser irradiation for 15 min owing to the excellent photothermal conversion ability of Ti 3 C 2 T x (90.1%) ( Figure S12, Supporting Information). ...
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... the photothermal curves of Zn-MOF@Ti 3 C 2 T x during on and off laser were measured, and the τ s value was calculated as 368.8 s (Figure 4e). As such, the photothermal conversion efficiency of the Zn-MOF@Ti 3 C 2 T x suspension is around 38.2%, higher than that of PDMS@Ti 3 C 2 T x /CNTs/Co film (29.5%), [54] Ag 2 S/Ti 3 C 2 -20 (27.8%), [15] Nb 2 C NSs (36.4%), [55] ICG@Mn/Cu/Zn-MOF@MnO 2 (30.1%), [56] and PDA@curcumin NPs (23.93%), [57] but lower than Ti 3 C 2 T x (90.1%) in this work ( Figure S12, Supporting Information). The photothermal stability of Zn-MOF@Ti 3 C 2 T x was investigated in five heating/cooling cycles (Figure 4f ), for which no apparent decline can be observed in the temperature. ...
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... the minimum inhibitory concentration (MIC) of Zn-MOF@Ti 3 C 2 T x for S. aureus is 100 μg mL À1 . Figure S14, Supporting Information, shows the growth curves of E. coli treated with various antibacterial agents under different conditions, for which the similar results for the antibacterial behavior can also be observed with S. aureus. The MIC values of Zn-MOF@Ti 3 C 2 T x against E. coli are 200 μg mL À1 . ...
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... cytotoxicity experiments with different samples under NIR light irradiation were also investigated. Figure S17, Supporting Information, demonstrates that the cytotoxicity of Zn-MOF, Ti 3 C 2 T x , and Zn-MOF@Ti 3 C 2 T x after 10 min treatment with NIR light irradiation increases with increasing their dosages. As compared, Zn-MOF@Ti 3 C 2 T x (100 μg mL À1 ) possesses more significant cytotoxicity than that treated with NIR light irradiation than that of the one without the treatment. ...
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... the healing phenomenon, such as new formation of vessels and hair follicles, is observed in the Zn-MOF@Ti 3 C 2 T x NIR(þ) group. Further, the antibacterial activity in vivo was also investigated by culturing the remnant bacteria in the infected tissue on day 9 ( Figure S18, Supporting Information). In the Zn-MOF@Ti 3 C 2 T x NIR(þ) group, the alive bacteria colonies (2.37%) are lower than those in the control and Zn-MOF@ Ti 3 C 2 T x NIR(À) groups (39.35%) (Figure 8f ), which is well in line with the in vitro antibacterial results. ...
Citations
... All hydrogels showed good swelling capacity. MXene nanoparticles all contain a large number of hydrophilic groups and show strong hydrophilicity (Rasool et al., 2016;Jin et al., 2021;Guo et al., 2022;Cooksley et al., 2023), but the equilibrium swelling rate of GelMA/ MXene hydrogels after the addition of MXene is lower than that of GelMA hydrogels. Our analysis suggests that this may be because the composite hydrogels formed by the two have smaller pore sizes and denser composite structures, leading to a decrease in swelling rate. ...
Introduction: Wound healing is a delicate and complex process influenced by many factors. The treatment of skin wounds commonly involves the use of wound dressings, which remain a routine approach. An ideal dressing can provide protection and a suitable environment for wound surfaces by maintaining moisture and exhibiting good biocompatibility, mechanical strength, and antibacterial properties to promote healing and prevent infection.
Methods: We encapsulated tick-derived antibacterial polypeptides (Os) as a model drug within a methylacrylyl gelatin (GelMA) hydrogel containing MXene nanoparticles. The prepared composite hydrogels were evaluated for their wound dressing potential by analyzing surface morphology, mechanical properties, swelling behavior, degradation properties, antibacterial activity, and cytocompatibility.
Results: The results demonstrated excellent mechanical strength, swelling performance, degradation behavior, and antibacterial activity of the prepared composite hydrogels, effectively promoting cell growth, adhesion, and expression of antibacterial peptide activity. A full-thickness rat wound model then observed the wound healing process and surface interactions between the composite hydrogels and wounds. The composite hydrogel significantly accelerated wound closure, reduced inflammation, and sped epithelial formation and maturation.
Discussion: Incorporating antibacterial peptides into GelMA provides a feasible strategy for developing excellent antibacterial wound dressings capable of tissue repair. In conclusion, this study presents a GelMA-based approach for designing antibacterial dressings with strong tissue regenerative ability.
... Moreover, some natural antibacterial agents can also be designed as bioactive linkers. Guo et al. utilized curcumin as a ligand to construct a Zn-MOF-based antibacterial platform, which shows high effectiveness in promoting wound healing for bacterial infections [25]. ...
Metal-organic frameworks (MOFs) are a highly versatile class of ordered porous materials, which hold great promise for different biomedical applications, including antibacterial therapy. In light of the antibacterial effects, these nanomaterials can be attractive for several reasons. First, MOFs exhibit a high loading capacity for numerous antibacterial drugs, including antibiotics, photosensitizers, and/or photothermal molecules. The inherent micro- or meso-porosity of MOF structures enables their use as nanocarriers for simultaneous encapsulation of multiple drugs resulting in a combined therapeutic effect. In addition to being encapsulated into an MOF’s pores, antibacterial agents can sometimes be directly incorporated into an MOF skeleton as organic linkers. Next, MOFs contain coordinated metal ions in their structure. Incorporation of Fe2/3+, Cu2+, Zn2+, Co2+, and Ag+ can significantly increase the innate cytotoxicity of these materials for bacteria and cause a synergistic effect. Finally, abundance of functional groups enables modifying the external surface of MOF particles with stealth coating and ligand moieties for improved drug delivery. To date, there are a number of MOF-based nanomedicines available for the treatment of bacterial infections. This review is focused on biomedical consideration of MOF nano-formulations designed for the therapy of intracellular infections such as Staphylococcus aureus, Mycobacterium tuberculosis, and Chlamydia trachomatis. Increasing knowledge about the ability of MOF nanoparticles to accumulate in a pathogen intracellular niche in the host cells provides an excellent opportunity to use MOF-based nanomedicines for the eradication of persistent infections. Here, we discuss advantages and current limitations of MOFs, their clinical significance, and their prospects for the treatment of the mentioned infections.
MXenes, a class of two-dimensional materials, exhibit considerable potential in wound healing and dressing applications due to their distinctive attributes, including biocompatibility, expansive specific surface area, hydrophilicity, excellent electrical conductivity,...
Nanotechnology has emerged as a cornerstone in contemporary research, marked by the advent of advanced technologies aimed at nanoengineering materials with diverse applications, particularly to address challenges in human health. Among these challenges, antimicrobial resistance (AMR) has risen as a significant and pressing threat to public health, creating obstacles in preventing and treating persistent diseases. Despite efforts in recent decades to combat AMR, global trends indicate an ongoing and concerning increase in AMR. The primary contributors to the escalation of AMR are the misuse and overuse of various antimicrobial agents in healthcare settings. This has led to severe consequences not only in terms of compromised treatment outcomes but also in terms of substantial financial burdens. The economic impact of AMR is reflected in skyrocketing healthcare costs attributed to heightened hospital admissions and increased drug usage. To address this critical issue, it is imperative to implement effective strategies for antimicrobial therapies. This comprehensive review will explore the latest scientific breakthroughs within the metal–organic frameworks and the use of mesoporous metallic oxide derivates as antimicrobial agents. We will explore their biomedical applications in human health, shedding light on promising avenues for combating AMR. Finally, we will conclude the current state of research and offer perspectives on the future development of these nanomaterials in the ongoing battle against AMR.
The production of hydrogen peroxide (H2O2) via the two‐electron electrochemical oxygen reduction reaction (2e⁻ ORR) is an essential alteration in the current anthraquinone‐based method. Herein, a single‐atom Co─O4 electrocatalyst is embedded in a defective and porous graphene‐like carbon layer (Co─O4@PC). The Co─O4@PC electrocatalyst shows promising potential in H2O2 electrosynthesis via 2e⁻ ORR, providing a high H2O2 selectivity of 98.8% at 0.6 V and a low onset potential of 0.73 V for generating H2O2. In situ surface‐sensitive attenuated total reflection Fourier transform infrared spectra and density functional theory calculations reveal that the electronic and geometric modification of Co─O4 induced by defective carbon sites result in decreased d‐band center of Co atoms, providing the optimum adsorption energies of OOH* intermediate. The H‐cell and flow cell assembled using Co─O4@PC as the cathode present long‐term stability and high efficiency for H2O2 production. Particularly, a high H2O2 production rate of 0.25 mol g⁻¹cat h⁻¹ at 0.6 V can be obtained by the flow cell. The in situ‐generated H2O2 can promote the degradation of rhodamine B and sterilize Staphylococcus aureus via the Fenton process. This work can pave the way for the efficient production of H2O2 by using Co─O4 single atom electrocatalyst and unveil the electrocatalytic mechanism.
Metal–organic frameworks (MOFs) and MXenes have demonstrated immense potential for biomedical applications, offering a plethora of advantages. MXenes, in particular, exhibit robust mechanical strength, hydrophilicity, large surface areas, significant light absorption potential, and tunable surface terminations, among other remarkable characteristics. Meanwhile, MOFs possess high porosity and large surface area, making them ideal for protecting active biomolecules and serving as carriers for drug delivery, hence their extensive study in the field of biomedicine. However, akin to other (nano)materials, concerns regarding their environmental implications persist. The number of studies investigating the toxicity and biocompatibility of MXenes and MOFs is growing, albeit further systematic research is needed to thoroughly understand their biosafety issues and biological effects prior to clinical trials. The synthesis of MXenes often involves the use of strong acids and high temperatures, which, if not properly managed, can have adverse effects on the environment. Efforts should be made to minimize the release of harmful byproducts and ensure proper waste management during the production process. In addition, it is crucial to assess the potential release of MXenes into the environment during their use in biomedical applications. For the biomedical applications of MOFs, several challenges exist. These include high fabrication costs, poor selectivity, low capacity, the quest for stable and water-resistant MOFs, as well as difficulties in recycling/regeneration and maintaining chemical/thermal/mechanical stability. Thus, careful consideration of the biosafety issues associated with their fabrication and utilization is vital. In addition to the synthesis and manufacturing processes, the ultimate utilization and fate of MOFs and MXenes in biomedical applications must be taken into account. While numerous reviews have been published regarding the biomedical applications of MOFs and MXenes, this perspective aims to shed light on the key environmental implications and biosafety issues, urging researchers to conduct further research in this field. Thus, the crucial aspects of the environmental implications and biosafety of MOFs and MXenes in biomedicine are thoroughly discussed, focusing on the main challenges and outlining future directions.
