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Metal‐organic framework‐based biomaterials for biomedical applications

2021; Institution of Engineering and Technology; Volume: 7; Issue: 3 Linguagem: Inglês

10.1049/bsb2.12012

2405-4518

Gang Luo, Yanan Jiang, Chaoming Xie, Xiong Lu,

Nanoplatforms for cancer theranostics

Biosurface and BiotribologyVolume 7, Issue 3 p. 99-112 REVIEWOpen Access Metal-organic framework-based biomaterials for biomedical applications Gang Luo, Gang Luo Key Laboratory of Advanced Technologies of Materials, Ministry of Education, School of Materials Science and Engineering, Yibin Institute of Southwest Jiaotong University, Southwest Jiaotong University, Chengdu, ChinaSearch for more papers by this authorYanan Jiang, Yanan Jiang Key Laboratory of Advanced Technologies of Materials, Ministry of Education, School of Materials Science and Engineering, Yibin Institute of Southwest Jiaotong University, Southwest Jiaotong University, Chengdu, ChinaSearch for more papers by this authorChaoming Xie, Corresponding Author Chaoming Xie [email protected] Key Laboratory of Advanced Technologies of Materials, Ministry of Education, School of Materials Science and Engineering, Yibin Institute of Southwest Jiaotong University, Southwest Jiaotong University, Chengdu, China Correspondence Xiong Lu and Chaoming Xie, Key Laboratory of Advanced Technologies of Materials, Ministry of Education, School of Materials Science and Engineering, Yibin Institute of Southwest Jiaotong University, Southwest Jiaotong University, Chengdu 610031, China. Email: [email protected] and [email protected]Search for more papers by this authorXiong Lu, Corresponding Author Xiong Lu [email protected] [email protected] orcid.org/0000-0001-6367-430X Key Laboratory of Advanced Technologies of Materials, Ministry of Education, School of Materials Science and Engineering, Yibin Institute of Southwest Jiaotong University, Southwest Jiaotong University, Chengdu, China Correspondence Xiong Lu and Chaoming Xie, Key Laboratory of Advanced Technologies of Materials, Ministry of Education, School of Materials Science and Engineering, Yibin Institute of Southwest Jiaotong University, Southwest Jiaotong University, Chengdu 610031, China. Email: [email protected] and [email protected]Search for more papers by this author Gang Luo, Gang Luo Key Laboratory of Advanced Technologies of Materials, Ministry of Education, School of Materials Science and Engineering, Yibin Institute of Southwest Jiaotong University, Southwest Jiaotong University, Chengdu, ChinaSearch for more papers by this authorYanan Jiang, Yanan Jiang Key Laboratory of Advanced Technologies of Materials, Ministry of Education, School of Materials Science and Engineering, Yibin Institute of Southwest Jiaotong University, Southwest Jiaotong University, Chengdu, ChinaSearch for more papers by this authorChaoming Xie, Corresponding Author Chaoming Xie [email protected] Key Laboratory of Advanced Technologies of Materials, Ministry of Education, School of Materials Science and Engineering, Yibin Institute of Southwest Jiaotong University, Southwest Jiaotong University, Chengdu, China Correspondence Xiong Lu and Chaoming Xie, Key Laboratory of Advanced Technologies of Materials, Ministry of Education, School of Materials Science and Engineering, Yibin Institute of Southwest Jiaotong University, Southwest Jiaotong University, Chengdu 610031, China. Email: [email protected] and [email protected]Search for more papers by this authorXiong Lu, Corresponding Author Xiong Lu [email protected] [email protected] orcid.org/0000-0001-6367-430X Key Laboratory of Advanced Technologies of Materials, Ministry of Education, School of Materials Science and Engineering, Yibin Institute of Southwest Jiaotong University, Southwest Jiaotong University, Chengdu, China Correspondence Xiong Lu and Chaoming Xie, Key Laboratory of Advanced Technologies of Materials, Ministry of Education, School of Materials Science and Engineering, Yibin Institute of Southwest Jiaotong University, Southwest Jiaotong University, Chengdu 610031, China. Email: [email protected] and [email protected]Search for more papers by this author First published: 08 June 2021 https://doi.org/10.1049/bsb2.12012Citations: 2AboutSectionsPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Abstract Metal-organic frameworks (MOFs) refer to porous coordination materials that are formed from the assembly of metal ions and organic ligands. They have unique features, such as a large specific surface area, multiple active sites, easy functionalisation, and adjustable biocompatibility. MOFs have recently been widely used in the field of biomedical engineering owing to their unique structures and properties. This has enabled them to replace traditional materials and effectively address several problems. Through continuous development, MOF-based biomaterials have been remarkably improved by clarifying the relationship between MOF structures and properties. As a result, they are being extensively studied in the fields of chemical and material science. MOF-based biomaterials can meet the growing demands for efficient materials in biomedical applications. This review first discusses the basic structure of MOFs, followed by their preparation and functionalisation methods. The biomedical applications of MOF-based biomaterials in the fields of antibacterial activity, tumour therapy, skin repair, and bone repair are then summarised. Finally, challenges and future perspectives in the biomedical applications of MOF-based biomaterials are outlined. 1 INTRODUCTION Metal-organic frameworks (MOFs), which are crystalline porous materials consisting of intra-molecular pores formed by the self-assembly of organic ligands and metal ions or clusters through coordination bonds [1], have been developed recently. The variable metal centres and organic ligands of the MOFs lead to diversity in their structures and functions [2]. The coordination configuration of the metal ions and the spatial geometry of the organic ligands must be first considered while designing a MOF for a particular function. These factors determine the spatial topology of the MOF, which in turn affects its properties and functional efficacy. The numerous combinations between the base material forming the metal node and the organic ligands of the MOFs have promoted the application of MOF substrates in various fields, such as molecule sensing [3], gas separation [4], molecule adsorption [5], drug delivery [6], and catalysis [7], especially in the biomedical field. In this review, we summarise the recent developments in the field of MOF-based biomaterials, with emphasis on their applications in microbial control, tumour therapy, wound healing, and bone regeneration (Figure 1). First, an overview of the synthesis and functionalisation of MOFs is presented. This is followed by a discussion on the features of MOFs and the recent advances in their applications in different fields. Finally, the challenges and future prospects of implementing MOF-based biomaterials in biomedical applications are outlined. FIGURE 1Open in figure viewerPowerPoint Metal-organic frameworks for biomedical applications 2 SYNTHESIS AND FUNCTIONALISATION OF MOFS The continuous development of modern synthesis technology has provided numerous techniques for the synthesis of MOFs, such as water/solvothermal synthesis [8], microwave-assisted and ultrasonic-assisted syntheses [9], microemulsion-based synthesis [10], mechanochemical synthesis [11], continuous flow synthesis [12], and electrochemical synthesis [13]. These methods have both advantages and disadvantages in terms of synthesis efficiency, the scale of production, and the physical and chemical properties of the obtained MOFs. This study reviews and compares the most commonly used synthesis methods for MOFs. The preparation of crystals through water/solvothermal synthesis is simple and easy to operate. It involves the dissolution of the metal ions and organic ligands in solvents, followed by their incubation in a reactor. The MOF crystals are obtained under high temperature and pressure after a fixed reaction time. Luo et al. [14] synthesised the MOF zeolitic imidazolate framework-8 (ZIF-8) by placing Zn2+ metal ions and the organic ligand 2-methylimidazole in an aqueous solution, which was then incubated at 40°C for 48 h and vacuum dried. Subsequently, ZIF-8 was used as a carrier to produce the controllable assembly of Au25 (SG) 18 nanoclusters in the inner and outer surfaces of the main frame of ZIF-8. This process was based on the coordination interaction between carboxyl groups and zinc ions in the thiol ligands on the surface of gold nanoclusters. Sun et al. [15] used FeCl3·6H2O as a source of metal ions, 2-amino terephthalic acid as an organic ligand, and dimethyl formamide (DMF) as a solvent. The mixture was added into a suspension of polymeric graphite-like carbon nitride (g-C3N4) and autoclaved at 110°C for 48 h to synthesise a g-C3N4-loaded MOF through heterojunction formation. This MOF was termed NH2-MIL-101(Fe)/g-C3N4. This product demonstrated excellent catalytic activity. For instance, the catalytic reduction of CO2 to carbon monoxide by NH2-MIL-101(Fe)/g-C3N4-30 wt.% was 3.6 and 6.9 times faster than those by the original NH2-MIL-101(Fe) and g-C3N4, respectively. However, the water/solvothermal method is not suitable for large-scale production because it has a long reaction time and requires a substantial amount of organic solvent and the maintenance of a harsh environment (characterised by high temperature, high pressure, etc.). The microwave synthesis method involves mixing the reaction reagent and solvent and placing the resulting solution in a microwave reactor. This method is advantageous because the reaction is relatively quick and the synthesis only takes tens of minutes, unlike the long reaction time of solvothermal synthesis. In addition, uniform heating permits the formation of nanoscale MOF particles. Laybourn et al. [16] used aluminium sulphate (Al2 [SO4]3·18H2O) and terephthalic acid (H2BDC) to synthesise the MOF MIL-53 (Al) in 4.3 s through the microwave method, which is the fastest MOF synthesis method reported thus far. This study confirmed the viability of using microwave technology to mass produce MOFs significantly faster than the conventional heating methods. Haque et al. [17] used ferric chloride hexahydrate (FeCl3·6H2O) and terephthalic acid (H2BDC) as raw materials to synthesise the MOF MIL-53 (Fe) through the traditional heating and microwave method. MIL-53 (Fe) was produced in approximately 1.5–2.5 h and 1.5–3 days through the microwave method and traditional heating reactions, respectively. These results confirm that microwave synthesis is faster than traditional heating methods. The mechanochemical synthesis method involves the replacement of thermal energy with mechanical energy. The MOFs are produced by mixing ligands and metal salts and grinding them with a ball mill. This procedure is economical, rapid, and environment-friendly and significantly reduces the amount of solvent used while simultaneously improving production efficiency. Friščić et al. [18] mixed ZnO and 2-methylimidazole (HMeIm) and ground them to produce ZIF-8 through a mechanochemical reaction (Figure 2). A small amount of acetic acid or water was also added to catalyse the reaction. FIGURE 2Open in figure viewerPowerPoint (a) Mechanical synthesis of zeolitic imidazolate framework-8 (ZIF-8) (b) Fragments of the ZIF-8 crystal structure [18] The ultrasonic method produces MOFs through the sonification of mixed raw materials. This method has a short reaction time. Qiu et al. [19] rapidly synthesised MOFs by using the ultrasonic method to combine copper acetate and homophthalic acid (H3BTC) in an ethanol solution. A yield of 75.3% was obtained after 5 min of ultrasonic irradiation. The diameters of the synthesised MOFs were 50–100 nm (5 and 10 min, as shown in Figure 3a and b) and increased over time. A reaction time of 30 min produced MOFs with diameters of 100–200 nm and lengths in excess of 100 mm (Figure 3c). Furthermore, a reaction time of 90 min produced MOFs with diameters of 700–900 nm (Figure 3d). Thus, MOFs with varying sizes can be efficiently synthesised through the ultrasonic method by providing different reaction times. FIGURE 3Open in figure viewerPowerPoint Transmission electron microscopy images of the Metal-organic frameworks (MOFs) synthesised through the ultrasonic method at reaction times of (a) 5 min, (b) 10 min, (c) 30 min, and (d) 90 min [19] MOFs can be functionalised to obtain the desired properties. The functionalisation of MOFs can occur before or after their synthesis. The functionalisation of MOFs before synthesis involves the introduction of functional groups into the organic ligands, followed by the adoption of an appropriate synthesis method [20]. This method may require specific conditions, and the introduction of functional groups is likely to affect the formation of the frame structure. Therefore, this approach is not applicable to all MOFs. Deng et al. [21] modified the organic ligands during the preparation of MOF-5, wherein -NH2, -Br, -NO2 and -(CH3)2, -C4H4, -(OC3H5)2, -(OC7H7)2 were modified on terephthalic acid ligands. The functional MOF-5 was obtained by establishing a coordination bond with the metal ion Zn2+. The results demonstrated that different functional groups were attached within the pores of the material of the MOF, thereby providing it with diverse functions. Custelcean et al. [22] developed a pyridyl ligand with a free carboxylic acid group. A coordinate bond was formed between a copper ion and the ligand to obtain the desired MOF. The free carboxylic acid groups in this MOF, which were introduced by pre-modification, can selectively recognise Cl(H2O)4- clusters. Thus, specific recognition of molecules can be performed with this MOF. Functionalisation of MOFs after synthesis is more common than pre-synthesis functionalisation [23]. It involves post-synthesis modification of prepared MOFs [24]. The modification does not affect the integrity of the overall framework. Therefore, chemical reactions can be carried out to modify the MOFs and design multifunctional MOF materials. However, this method has several stringent requirements to ensure the stability of the MOFs. Sarker et al. [25] synthesised a stable, porous MOF named Zr-diaminostyrene dicarboxylic acid (Zr-DASDCA). The MOF was modified with oxaloyl chloride (OC) or p-benzoyl chloride (TC) after its synthesis to introduce different functional groups into Zr-DASDCA. The original MOF and functionalised post-MOF were both used as potential carriers for ibuprofen (IBU) storage and delivery. It was observed that the functionalised MOF reduced the release rate of IBU and stabilised its release for 10 days. Mortazavi et al. [26] used cysteamine molecules that contained amine and thiol groups to functionalise MIL-101 (Cr), thereby producing MIL-101 (Cr)-SH. It was oxidised with H2O2 and then acidified with dilute sulphuric acid to produce the MIL-101 (Cr)-SO3H nano-catalyst. The activity of the prepared catalyst was then evaluated. It was observed that the conversion rate of MIL-101-SO3H into benzaldehyde was equal to 90% after 3 h. This was a significant improvement over the rates obtained from the blank test (25%) and the application of pure MIL-101 as catalyst (43%). These results demonstrated that the catalytic activity of MIL-101 (Cr) was significantly improved after functionalisation. 3 METAL-ORGANIC FRAMEWORK-BASED BIOMATERIALS FOR ANTIBACTERIAL APPLICATIONS Bacterial resistance has become an issue of grave concern. There is an urgent requirement for alternative antimicrobial biomedicines. Traditional antibacterial agents consist of antibiotics [27], chitosan, quaternary ammonium salts, and metal ions. Most of these antibacterial agents are highly toxic, have a poor antibacterial effect, and are subject to several limitations. Therefore, the preparation of effective antibacterial materials to ensure medical safety has become a challenge. In addition to being composed of metal ions and organic ligands, MOFs have a porous structure, a large specific surface area, and several semiconductor-like properties. The antimicrobial features and mechanisms of MOFs are discussed in this section, followed by a review of the several applications of MOFs in antibacterial biology. Metal-organic framework-based antibacterial nanomaterials MOFs exhibited antibacterial activity because of their unique metal coordination structure which can release antibacterial metal ions, such as zinc (Zn2+) and copper (Cu+/Cu2+), during degradation. These metal ions encounter the microbial cell membrane and are attracted to the negatively charged cell membrane through Coulomb attraction, leading to the formation of a solid complex. The active centre of the cell synthase is composed of functional groups, such as the sulfhydryl, amino, and hydroxyl groups. The metal ions can penetrate the bacterial cell membrane and react with the functional groups attached to these proteins. As a result, the structure of the active centre of the protein is destroyed, resulting in the death of the microorganism or the loss of its proliferation ability. Berchel et al. [28] studied Ag-MOFs that consisted of an organic portion of 3-phosphonylbenzoic acid with an Ag+ metal ligand. Ag-MOFs demonstrated good antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. Yang et al. [29] developed MOF (ZIF-8) nanocrystals on cotton fibres and coated them with polydimethylsiloxane (PDMS). The prepared cotton fabric was superhydrophobic and had antimicrobial properties (Figure 4). The interaction between the Zn2+ ions released by ZIF-8 and the cell membrane proteins destroyed the cell structure of the bacteria, resulting in membrane internalisation and cell death. As a result, this material had excellent antibacterial properties against E. coli and S. aureus. In addition, the fabric maintained its superhydrophobic and antibacterial nature even after being subjected to 3000 cycles of abrasion and 5 cycles of washing. FIGURE 4Open in figure viewerPowerPoint Preparation of a Metal-organic framework (MOF)-based superhydrophobic and antibacterial cotton fabric [29] Application of Metal-organic framework-based biomaterials as antibacterial drug carriers Owing to their high porosity and large surface area, MOFs can be used as antimicrobial drug carriers, which can be released continuously for their therapeutic purpose. Wu et al. [30] developed MOF-53 (Fe), which was a porous iron-carboxylate MOF that was composed of iron ions and terephthalic acid to encapsulate the drug vancomycin (VAN; Figure 5). This MOF had good chemical stability and a high drug-loading capacity under acidic conditions (at pH values of 7.4, 6.5, and 5.5). The results of this study indicated that the drug-loading ratio of VAN and the antibacterial ratio of the MOF-53 (Fe)/VAN system against S. aureus were increased to 20 wt.% and 90%, respectively. In addition, the MOF-53 (Fe)/VAN system was highly biocompatible. FIGURE 5Open in figure viewerPowerPoint Schematic of the Metal-organic framework (MOF)-53 (Fe) structure, and the loading and delivery of MOF-packaged drug molecules to kill bacteria [30] Shakya et al. [31] used biocompatible cyclodextrin (CD)-MOF as a template to develop a mesoporous CD-MOF skeleton by binding γ-cyclodextrin (γ-CD) to a potassium metal salt. [email protected], a CD-MOF that was loaded with ultrafine Ag nanoparticles (Ag NPs), was then synthesised by using tiny windows with a diameter of 1.7 nm to restrict the growth of Ag NPs in the CD-MOF structure. The chemical cross-linking of the CD unit on the surface of the particle through a carbonate bond was followed by attaching several ultrafine Ag NPs in the particle to obtain the desired reduction in the drug release rate and the persistent antibacterial effect. The results of antimicrobial assays demonstrated that the minimum inhibitory concentration (MIC) values of [email protected] against E. coli and S. aureus were 16 μg/ml and 128 μg/ml, respectively. Su et al. [32] successfully prepared voriconazole-inbuilt zinc 2-methylimidazolate frameworks (V-ZIF) that contained an antifungal drug named voriconazole. They combined Zn2+ ions, which were obtained from zinc nitrate, with the ligand of voriconazole. The acidic environment of Candida albicans biofilms can trigger the separation of voriconazole from the metal-organic skeleton, resulting in the release of voriconazole. V-ZIF can penetrate C. albicans biofilms and prevent their expansion through the superior diffusion of voriconazole, thereby resulting in fungal cell membrane damage and the eventual death of C. albicans. V-ZIF demonstrated good antifungal properties when used on C. albicans infected wounds, in addition to promoting wound healing without obvious side effects. Gallis et al. [33] used ZIF-8 to encapsulate an antimicrobial drug ceftazidime to treat intracellular infections. The results showed that the drug could be released from ZIF-8 for up to a week. Thus, ceftazidime-encapsulated ZIF-8 showed excellent antibacterial activity against E. coli, and its antibacterial activity was determined by the degradation kinetics of ZIF-8. Metal-organic framework-based biomaterials for photothermal antibacterial agents The combination of different metal ions and ligands in MOFs allows them to be used as photothermal agent for heating and antibacterial activities. Han et al. [34] inserted Cu2+ into the porphyrin ring of a MOF. The photothermal effect of the Cu-MOF was enhanced due to the d-d transition. Cu2+ doped particles can also trap electrons, thereby enhancing their photocatalytic performances. Thus, doping the MOF with 10% Cu2+ made it an effective antibacterial agent. It reduced the count of S. aureus cells by 99.71% within 20 min of exposure to light radiation at 660 nm (0.4 W/cm2). In addition, in vivo results demonstrated that the Cu-MOFs could efficiently kill bacteria. Luo et al. [35] prepared a core-shell bimetallic organic framework by using Prussian blue ([email protected]) and porphyrin-doped UIO-66-TCPP MOF as the core and shell, respectively. [email protected] reported a maximum photothermal conversion efficiency of 29.9% under near-infrared (NIR) light irradiation at 808 nm. This material displayed weak antibacterial characteristics under irradiation of 808 nm or 660 nm for 10 min. However, the material's antibacterial ratios against S. aureus and E. coli after 10 min of irradiation by a double-light lamp were 99.31% and 98.68%, respectively. Figure 6 shows the rapid sterilisation mechanism of [email protected] FIGURE 6Open in figure viewerPowerPoint Schematic of the antibacterial nature of [email protected] under double light irradiation [35] MOF, Metal-organic frameworks; PB, Prussian blue Metal-organic framework-based biomaterials for photodynamic antibacterial agents Photodynamic antimicrobial agents utilise light to stimulate the transition of a photosensitiser from its low-energy ground state to a high-energy triplet state. The free electrons generated in this reaction can target biological molecules of microorganisms or trigger a similar photodynamic reaction in free radicals. Alternatively, the triplet photosensitiser molecules interact with the first triplet oxygen molecules to produce singlet oxygen, which is toxic for the target microorganisms and can inactivate them. Because the properties of MOFs are similar to those of semi-conductors, they can be used as photosensitisers exhibiting photodynamic antibacterial activity. Pingli et al. [36] filtered various MOFs by analysing their photocatalytic activity. They identified ZIF-8, a MOF with ultra-high photocatalytic bactericidal activity, capable of killing E. coli in water. ZIF-8 had a bactericidal rate in excess of 99.9999% after being subjected to sunlight for 2 h. This led to the development of a novel and highly efficient integrated air filter through the hot-pressing method. This filter trapped more than 98% of the particulate matter and killed 99.99% of the bacteria in the air. This effect is attributed to the photo-generated electrons that are derived from ligand to metal charge transfer (LMCT) under the action of sunlight. These electrons activate O2 to form O2− and H2O2, which can oxidise the pathogenic bacteria in the air, thereby killing them. Nie et al. [37] attached graphene quantum dots (GQDs) and MOF (PCN-224) on the surface of a cotton fibre through chemical coupling and in situ growth, respectively. GQDs with fluorescence resonance energy transfer (FRET) pairs that served as donors and PCN-224 as receptors were developed to study the photodynamic antibacterial activity of self-sterilised fabrics against gram-negative and gram-positive bacteria (Figure 7). The results showed that the incorporation of FRET pairs increased the production of 1O2 by 1.61 times. The fabric reported high bactericidal efficiency (>99% against four bacterial strains within 30 min) and low cytotoxicity. FIGURE 7Open in figure viewerPowerPoint Schematic of the antibacterial effect of cotton fibres loaded with graphene quantum dots (GQDs) and PCN-224 [37] Qu et al. [38] synthesised a porphyrin-based MOF nano-platform (PMOF) that had high biofilm penetration abilities, high oxygen self-generation, and was highly efficient in photodynamic therapy. The PMOF particles were then encapsulated in human serum albumin (HSA)-coated manganese dioxide (MnO2) through biomineralisation under alkaline conditions to produce a multi-component nano-platform (MMNP). The results of the antibacterial assays demonstrated that the addition of H2O2 enhanced the bactericidal ability of the material (antibacterial ratios against E. coli and S. aureus were 99% and 90%, respectively). The nano-platform was used to treat subcutaneous abscesses infected with S. aureus in vivo without damaging healthy tissues and produced a very significant therapeutic effect. Metal-organic framework-based biomaterials for combinatory antibacterial therapy In addition to individual antimicrobial treatment, synergistic therapeutic antimicrobial treatment can also be performed by utilising MOFs. Antimicrobials based on photothermal therapy (PTT) and photodynamic therapy (PDT) have disadvantages if they are used individually. The high temperatures required for PTT can burn healthy tissues, whereas the photodynamic molecules of PDT may not be very effective. Therefore, combinatory therapy must be given more importance while designing MOF-based antibacterial biomaterials. Zhao et al. [39] developed a novel MOF/Ag-derived nanocomposite material that was used for synergistic antibacterial treatment. It was capable of releasing a large number of Ag ions and exhibited a strong photothermal conversion effect. This material was produced by first synthesising zinc-based and graphite-based MOF derivatives, followed by the uniform introduction of Ag NPs through a Zn–Ag+ substitution reaction. The prepared nanomaterial generated sufficient heat to destroy the bacterial membrane upon being irradiated with an NIR laser at 808 nm (3 W/cm2) for 10 min. In addition, several Zn2+ and Ag + ions were released simultaneously, thereby causing chemical damage to the intracellular components of bacterial substances. Antibacterial assays demonstrated that this dual antibacterial action ensured that the antibacterial ratio of the nanocomposite was approximately 100% at a very low dosage (0.16 mg/ml) against a high concentration of bacteria. Wu et al. [40] developed a MOF named ZIF-8-ICG by encapsulating the photothermal agent, indocyanine green (ICG). The ICG component of ZIF-8-ICG effectively generated heat in response to NIR laser radiation, resulting in the precise, rapid, and effective photothermal killing of bacteria. Zn2+ was simultaneously released from the ZIF-8 and inhibited bacterial growth by increasing the permeability of the bacterial cell membranes. This enhanced the efficacy of the photothermal therapy by reducing the heat resistance of the bacteria. Fan et al. [41] developed two-dimensional carbon nanosheets (2D-CNS) that were derived from a MOF and could trigger phase transformation and local bacterial eradication, thereby enhancing anti-infection therapy. MOF-derived ZnO-doped graphene ([email protected]) was first synthesised and immobilised on a phase-change thermal response brush (TRB) through in situ polymerisation to produce [email protected] [email protected] has a flexible two-dimensional nanostructure and exhibits high photothermal activity, continuous release of Zn2+, and switchable phase-size conversion. The bacteria gathered near the material were killed upon subjecting it to NIR irradiation due to the penetration of several Zn2+ ions, physical cutting, and hyperthermia. These processes contributed synergistically to the destruction of the bacterial membrane and intracellular material. The bactericidal ratio of this synergistic system against E. coli and S. aureus was approximately 100% in a short period, without causing the accumulation of toxic compounds or damage to healthy tissues. Although MOFs are widely used because of its antibacterial properties, MOFs-based antibacterial materials also have some disadvantages. The insufficient effect of single antibacterial and the potential toxicity of MOFs limited the clinical applications. 4 METAL-ORGANIC FRAMEWORK-BASED BIOMATERIALS FOR TUMOR THERAPY Cancer has become a major disease that is endangering the lives and health of several people worldwide. Clinical