Size and surface controllable metal-organic frameworks (MOFs) for fluorescence imaging and cancer therapy

Metal-organic frameworks for biomedical applications: A review

Metal-organic frameworks (MOFs) are emergent materials in diverse prospective biomedical uses, owing to their inherent features such as adjustable pore dimension and volume, well-defined active sites, high surface area, and hybrid structures. The multifunctionality and unique chemical and biological characteristics of MOFs allow them as ideal platforms for sensing numerous emergent biomolecules with real-time monitoring towards the point-of-care applications. This review objects to deliver key insights on the topical developments of MOFs for biomedical applications. The rational design, preparation of stable MOF architectures, chemical and biological properties, biocompatibility, enzyme-mimicking materials, fabrication of biosensor platforms, and the exploration in diagnostic and therapeutic systems are compiled. The state-of-the-art, major challenges, and the imminent perspectives to improve the progressions convoluted outside the proof-of-concept, especially for biosensor platforms, imaging, and photodynamic therapy in biomedical research are also described. The present review may excite the interdisciplinary studies at the juncture of MOFs and biomedicine.

Targeted cancer treatment using folate-conjugated sponge-like ZIF-8 nanoparticles: a review

ZIF-8 (zeolitic imidazolate framework-8) is a potential drug delivery system because of its unique properties, which include a large surface area, a large pore capacity, a large loading capacity, and outstanding stability under physiological conditions. ZIF-8 nanoparticles may be readily functionalized with targeting ligands for the identification and absorption of particular cancer cells, enhancing the efficacy of chemotherapeutic medicines and reducing adverse effects. ZIF-8 is also pH-responsive, allowing medication release in the acidic milieu of cancer cells. Because of its tunable structure, it can be easily functionalized to design cancer-specific targeted medicines. The delivery of ZIF-8 to cancer cells can be facilitated by folic acid-conjugation. Hence, it can bind to overexpressed folate receptors on the surface of cancer cells, which holds the promise of reducing unwanted deliveries. As a result of its importance in cancer treatment, the folate-conjugated ZIF-8 was the major focus of this review.

Post-synthetic modified luminescent metal-organic framework for the detection of berberine hydrochloride in a traditional Chinese herb

In this work, a novel fluorescence sensor UiO-66-PSM based on post-synthetic modified metal-organic frameworks was prepared for the detection of berberine hydrochloride (BBH) in the traditional Chinese herb Coptis. UiO-66-PSM was synthesized by a simple Schiff base reaction with UiO-66-NH2 and phthalaldehyde (PAD). The luminescence quenching can be attributed to the photo-induced electron transfer process from the ligand of UiO-66-PSM to BBH. The UiO-66-PSM sensor exhibited fast response time, low detection limit, and high selectivity to BBH. Moreover, the UiO-66-PSM sensor was successfully applied to the quantitative detection of BBH in the traditional Chinese herb Coptis, and the detection results obtained from the as-fabricated fluorescence sensing assay were consistent with those of high-performance liquid chromatography (HPLC), indicating that this work has potential applicability for the detection of BBH in traditional Chinese herbs.

Magnetic UiO-66-NH2 Core-Shell Nanohybrid as a Promising Carrier for Quercetin Targeted Delivery toward Human Breast Cancer Cells

In this study, a magnetic core-shell metal-organic framework (MOF) nanocomposite, Fe3O4-COOH@UiO-66-NH2, was synthesized for tumor-targeting drug delivery by incorporating carboxylate groups as functional groups onto ferrite nanoparticle surfaces, followed by fabrication of the UiO-66-NH2 shell using a facile self-assembly approach. The anticancer drug quercetin (QU) was loaded into the magnetic core-shell nanoparticles. The synthesized magnetic nanoparticles were comprehensively evaluated through multiple techniques, including FT-IR, PXRD, FE-SEM, TEM, EDX, BET, UV-vis, ZP, and VSM. Drug release investigations were conducted to investigate the release behavior of QU from the nanocomposite at two different pH values (7.4 and 5.4). The results revealed that QU@Fe3O4-COOH@UiO-66-NH2 exhibited a high loading capacity of 43.1% and pH-dependent release behavior, maintaining sustained release characteristics over a prolonged duration of 11 days. Furthermore, cytotoxicity assays using the human breast cancer cell line MDA-MB-231 and the normal cell line HEK-293 were performed to evaluate the cytotoxic effects of QU, UiO-66-NH2, Fe3O4-COOH, Fe3O4-COOH@UiO-66-NH2, and QU@Fe3O4-COOH@UiO-66-NH2. Treatment with QU@Fe3O4-COOH@UiO-66-NH2 substantially reduced the cell viability in cancerous MDA-MB-231 cells. Cellular uptake and cell death mechanisms were further investigated, demonstrating the internalization of QU@Fe3O4-COOH@UiO-66-NH2 by cancer cells and the induction of cancer cell death through the apoptosis pathway. These findings highlight the considerable potential of Fe3O4-COOH@UiO-66-NH2 as a targeted nanocarrier for the delivery of anticancer drugs.

Smart Nanomaterials in Cancer Theranostics: Challenges and Opportunities

Cancer is ranked as the second leading cause of death globally. Traditional cancer therapies including chemotherapy are flawed, with off-target and on-target toxicities on the normal cells, requiring newer strategies to improve cell selective targeting. The application of nanomaterial has been extensively studied and explored as chemical biology tools in cancer theranostics. It shows greater applications toward stability, biocompatibility, and increased cell permeability, resulting in precise targeting, and mitigating the shortcomings of traditional cancer therapies. The nanoplatform offers an exciting opportunity to gain targeting strategies and multifunctionality. The advent of nanotechnology, in particular the development of smart nanomaterials, has transformed cancer diagnosis and treatment. The large surface area of nanoparticles is enough to encapsulate many molecules and the ability to functionalize with various biosubstrates such as DNA, RNA, aptamers, and antibodies, which helps in theranostic action. Comparatively, biologically derived nanomaterials perceive advantages over the nanomaterials produced by conventional methods in terms of economy, ease of production, and reduced toxicity. The present review summarizes various techniques in cancer theranostics and emphasizes the applications of smart nanomaterials (such as organic nanoparticles (NPs), inorganic NPs, and carbon-based NPs). We also critically discussed the advantages and challenges impeding their translation in cancer treatment and diagnostic applications. This review concludes that the use of smart nanomaterials could significantly improve cancer theranostics and will facilitate new dimensions for tumor detection and therapy.

Metal-Organic Framework (MOF)-A Universal Material for Biomedicine

Metal-organic frameworks (MOFs) are a very promising platform for applications in various industries. In recent years, a variety of methods have been developed for the preparation and modification of MOFs, providing a wide range of materials for different applications in life science. Despite the wide range of different MOFs in terms of properties/sizes/chemical nature, they have not found wide application in biomedical practices at present. In this review, we look at the main methods for the preparation of MOFs that can ensure biomedical applications. In addition, we also review the available options for tuning the key parameters, such as size, morphology, and porosity, which are crucial for the use of MOFs in biomedical systems. This review also analyses possible applications for MOFs of different natures. Their high porosity allows the use of MOFs as universal carriers for different therapeutic molecules in the human body. The wide range of chemical species involved in the synthesis of MOFs makes it possible to enhance targeting and prolongation, as well as to create delivery systems that are sensitive to various factors. In addition, we also highlight how injectable, oral, and even ocular delivery systems based on MOFs can be used. The possibility of using MOFs as therapeutic agents and sensitizers in photodynamic, photothermal, and sonodynamic therapy was also reviewed. MOFs have demonstrated high selectivity in various diagnostic systems, making them promising for future applications. The present review aims to systematize the main ways of modifying MOFs, as well as the biomedical applications of various systems based on MOFs.

Nanoproteomics deciphers the prognostic value of EGFR family proteins-based liquid biopsy

Monitoring tumor-associated protein status in serum can effectively track tumors and avoid time-consuming, costly, and invasive tissue biopsy. Epidermal growth factor receptor (EGFR) family proteins are often recommended in the clinical management of multiple solid tumors. However, the low-abundance of serum EGFR (sEGFR) family proteins hinders the depth-understanding of their function and tumor management. Herein, a nanoproteomics approach coupling with aptamer-modified MOFs (NMOFs-Apt) with mass spectrometry was developed for the enrichment and quantitative analysis of sEGFR family proteins. This nanoproteomics approach exhibited high sensitivity and specificity for sEGFR family protein quantification, with the limit of quantification as low as 1.00 nM. After detecting 626 patients' sEGFR family proteins with various malignant tumors, we concluded that the levels of serum proteins had a moderate concordance with tissue counterparts. Metastatic breast cancer patients with a high level of serum human epidermal growth factor receptor 2 (sHER2) and a low level of sEGFR had a poor prognosis, and patients with a sHER2 decrease of more than 20% had longer disease-free time after receiving chemotherapy. This nanoproteomics method provided a simple and effective approach for low-abundant serum protein detection and our results clarified the potential of sHER2 and sEGFR as cancer markers.

Metal-organic frameworks-based biosensor for microRNA detection in prostate cancer cell lines

In this research, a novel dye-labeled probe (FAM-Probe) based on a nano metal-organic framework (NMOF) functionalized with folate (NMOF-FA) was prepared and applied as a fluorescent sensing platform for the recognition of intracellular microRNA (miRNA-21) in DU145, PC3, and LNCaP cancer cells. The NMOF-FA can be easily assembled with a dye-labeled miR-21 probe (FAM-Probe21), causing an efficient fluorescence quenching of fluorescence of FAM fluorophore. The probe can be specifically catch up by cancerous cells through targeting their folate receptor by folic acid on the FAM-Probe21-NMOF-FA complex. Upon the interaction of the FAM-Probe21-NMOF-FA with complementary miRNA (miR-21), the fluorescence intensity can be recovered, providing a specific system to detect miRNAs in prostate cancer cells. We used the proposed probe for cell-specific intracellular miRNA-21 sensing, following the alteration expression level of miRNA-21 inside living cells. Thus, the FAM-Probe21-NMOF-FA complex can be used as a new miRNA sensing method in biomedicine studies.

Layered double hydroxide-based nanomaterials for biomedical applications

Against the backdrop of increased public health awareness, inorganic nanomaterials have been widely explored as promising nanoagents for various kinds of biomedical applications. Layered double hydroxides (LDHs), with versatile physicochemical advantages including excellent biocompatibility, pH-sensitive biodegradability, highly tunable chemical composition and structure, and ease of composite formation with other materials, have shown great promise in biomedical applications. In this review, we comprehensively summarize the recent advances in LDH-based nanomaterials for biomedical applications. Firstly, the material categories and advantages of LDH-based nanomaterials are discussed. The preparation and surface modification of LDH-based nanomaterials, including pristine LDHs, LDH-based nanocomposites and LDH-derived nanomaterials, are then described. Thereafter, we systematically describe the great potential of LDHs in biomedical applications including drug/gene delivery, bioimaging diagnosis, cancer therapy, biosensing, tissue engineering, and anti-bacteria. Finally, on the basis of the current state of the art, we conclude with insights on the remaining challenges and future prospects in this rapidly emerging field.

Bifunctional Metal-Organic Framework Functionalized by Dimethylamine Cations: Proton Conduction and Iodine Vapor Adsorption

A metal-organic framework, {Zn₃(BTB)₂(μ₃-OH)[(CH₃)₂NH₂](H₂O)}_n (1), was synthesized based on H₃BTB (1,3,5-tri(4-carboxyphenyl)benzene). An AC impedance test proves that 1 has a relatively high conductivity performance of 1.52 × 10^-3 S·cm^-1 at 338 K and 98% RH. The proton conductivity of the composite film 1@CS-9 (CS = chitosan) reaches 1.84 × 10^-1 S·cm^-1 at 328 K and 98% RH. In addition, 1 is discovered to have a good adsorption effect on iodine vapor, and the adsorption capacity reaches 726 mg·g^-1. The multifunctionality caused by dimethylamine cations was investigated for the first time, which has implications for multifunctionality generated by host-guest molecules.

Doxorubicin-Loaded Core–Shell UiO-66@SiO2 Metal–Organic Frameworks for Targeted Cellular Uptake and Cancer Treatment

Beneficial features of biocompatible high-capacity UiO-66 nanoparticles, mesoporous SiO₂, and folate-conjugated pluronic F127 were combined to prepare the core–shell UiO-66@SiO₂/F127-FA drug delivery carrier for targeted cellular uptake in cancer treatment. UiO-66 and UiO-66-NH₂ nanoparticles with a narrow size and shape distribution were used to form a series of core–shell MOF@SiO₂ structures. The duration of silanization was varied to change the thickness of the SiO₂ shell, revealing a nonlinear dependence that was attributed to silicon penetration into the porous MOF structure. Doxorubicin encapsulation showed a similar final loading of 5.6 wt % for both uncoated and silica-coated particles, demonstrating the potential of the nanocomposite’s application in small molecule delivery. Silica coating improved the colloidal stability of the composites in a number of model physiological media, enabled grafting of target molecules to the surface, and prevented an uncontrolled release of their cargo, with the drawback of decreased overall porosity. Further modification of the particles with the conjugate of pluronic and folic acid was performed to improve the biocompatibility, prolong the blood circulation time, and target the encapsulated drug to the folate-expressing cancer cells. The final DOX-loaded UiO-66@SiO₂/F127-FA nanoparticles were subjected to properties characterization and in vitro evaluation, including studies of internalization into cells and antitumor activity. Two cell lines were used: MCF-7 breast cancer cells, which have overexpressed folate receptors on the cell membranes, and RAW 264.7 macrophages without folate overexpression. These findings will provide a potential delivery system for DOX and increase the practical value of MOFs.

Five-FU@CuS/NH2 -UiO-66 as a drug delivery system for 5-fluorouracil to colorectal cancer cells

In this study, copper sulfide nanoparticles (CuS-NPs), which can improve the antiproliferative properties of conventional anticancer drugs such as 5-fluorouracil (5-FU), were incorporated into the pores of amine-functionalized UiO-66 (CuS/NH₂ -UiO-66). The introduced nano-drug delivery system was exerted to perform an in vitro treatment on CT-26 mouse colorectal cancer cells. The synthesized final product was labeled as 5-FU@CuS/NH₂ -UiO-66 and characterized through conventional methods including X-ray diffraction (XRD), Fourier transformation infrared spectroscopy (FT-IR), Brunauer-Emmett-Teller (BET) analysis, Ultraviolet-Visible (UV-Vis) analysis, Inductively coupled plasma mass spectrometry (ICP-MS), and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. In contrast to 5-FU, the outcomes of the cytotoxicity assay lacked any comparable results for 5-FU@CuS/NH₂ -UiO-66.

Bioimaging guided pharmaceutical evaluations of nanomedicines for clinical translations

Nanomedicines (NMs) have emerged as an efficient approach for developing novel treatment strategies against a variety of diseases. Over the past few decades, NM formulations have received great attention, and a large number of studies have been performed in this field. Despite this, only about 60 nano-formulations have received industrial acceptance and are currently available for clinical use. Their in vivo pharmaceutical behavior is considered one of the main challenges and hurdles for the effective clinical translation of NMs, because it is difficult to monitor the pharmaceutic fate of NMs in the biological environment using conventional pharmaceutical evaluations. In this context, non-invasive imaging modalities offer attractive solutions, providing the direct monitoring and quantification of the pharmacokinetic and pharmacodynamic behavior of labeled NMs in a real-time manner. Imaging evaluations have great potential for revealing the relationship between the physicochemical properties of NMs and their pharmaceutical profiles in living subjects. In this review, we introduced imaging techniques that can be used for in vivo NM evaluations. We also provided an overview of various studies on the influence of key parameters on the in vivo pharmaceutical behavior of NMs that had been visualized in a non-invasive and real-time manner.

Nanoporous {Y2}-Organic Frameworks for Excellent Catalytic Performance on the Cycloaddition Reaction of Epoxides with CO2 and Deacetalization-Knoevenagel Condensation

Stable metal-organic frameworks containing periodically arranged nanosized pores and active Lewis acid-base active sites are considered as ideal candidates for efficient heterogeneous catalysis. Herein, the exquisite combination of [Y₂(CO₂)₇(H₂O)₂] cluster (abbreviated as {Y₂}) and multifunctional linker of 2,4,6-tri(2,4-dicarboxyphenyl)pyridine (H₆TDP) led to a nanoporous framework of {[Y₂(TDP)(H₂O)₂]·5H₂O·4DMF}_n (NUC-53, NUC = North University of China), which is a rarely reported binuclear three-dimensional (3D) framework with hierarchical tetragonal-microporous (0.78 nm) and octagonal-nanoporous (1.75 nm) channels. The inner walls of these channels are aligned by {Y₂} clusters and plentifully coexisted Lewis acid-base sites of Y^III ions and N_pyridine atoms. Furthermore, NUC-53 has a quite large void volume of ∼65.2%, which is significantly higher than most documented 3D rare-earth-based MOFs. The performed catalytic experiments exhibited that activated NUC-53 showed a high catalytic activity on the cycloaddition reactions of CO₂ with styrene oxide under mild conditions with excellent turnover number (TON: 1980) and turnover frequency (TOF: 495 h^-1). Moreover, the deacetalization-Knoevenagel condensation reactions of benzaldehyde dimethyl acetal and malononitrile could be efficiently prompted by the heterogeneous catalyst of NUC-53. These findings not only pave the way for the construction of nanoporous MOF based on rare-earth clusters with a variety of catalytic activities but also provide some new insights into the catalytic mechanism.

Lipid membrane anchoring and highly specific fluorescence detection of cancer-derived exosomes based on postfunctionalized zirconium-metal-organic frameworks

Cancer-derived exosomes carry a variety of important biomarkers specific to the formation, invasion and metastasis of tumor tissue. Dynamic monitoring of exosomes originated from cancer cells has clinical significance. Here we proposed a novel method to employ zirconium-metal-organic frameworks (Zr-MOFs) for extracting and identifying exosomes from blood. At first UiO-66 was magnetically modified as the adsorbent to anchor exosomes by forming Zr-O-P bonds. Then UiO-66-NH₂ modified with anti-EpCAM was used to construct the fluorescent probe to recognize the extracted EpCAM-positive exosomes by forming a "MOF-exosome-MOF" structure. The proposed fluorescence detection method was evaluated by quantifying MCF-7 cell-derived exosomes at the concentration as low as 16.72 particles/μl. This method was successfully applied to analyze exosomes in the plasma samples from healthy donors and breast cancer patients, demonstrating that our method might have a great potential in assisting the early diagnosis and in dynamically monitoring the efficacy of cancer treatment. We believe that the method could be extended to the detection of other biomarkers in exosomes derived from cancer cell.

ATP-responsive near-infrared fluorescent nanoparticles for synergistic chemotherapy and starvation therapy

Cancer is a major public health problem worldwide, and traditional chemotherapy or a single therapeutic strategy often fails to achieve expected results in cancer treatment. Thus, the development of a method to realize controlled drug delivery and synergistic therapy is required. Herein, MOF-based nanoparticles named RhI-DOX-GOD@ZIF-90 are synthesized using RhI (a near-infrared fluorescent dye), DOX (an anti-cancer drug) and GOD (glucose oxidase). RhI and DOX are encapsulated inside the ZIF-90 framework and GOD is loaded on the surface of ZIF-90. Owing to the fact that the ATP level in cancer cells is abnormally higher than that in normal cells, RhI-DOX-GOD@ZIF-90 nanoparticles are destructed only in cancer cells. RhI is released to give outstanding NIR emission and realize controlled drug delivery. DOX is released and cancer cells are killed by chemotherapy. Also, GOD is released to consume glucose and achieve the purpose of starving the cancer cells. By making full use of the advantages of near-infrared emission, RhI-DOX-GOD@ZIF-90 nanoparticles can be used to image ATP in tumor-bearing mice. At the same time, DOX and GOD can be released accurately at tumor sites of mice and excellent anti-tumor efficiency by synergistic chemotherapy and starvation therapy is achieved.

Application progress of magnetic molecularly imprinted polymers chemical sensors in the detection of biomarkers

Specific recognition and highly sensitive detection of biomarkers play an essential role in identification, early diagnosis and prevention of many diseases. Magnetic molecularly imprinted polymers (MMIPs) have been widely used to capture biomimetic receptors for targets in various complex matrices due to their superior recognition ability, structural stability, and rapid separation characteristics, which overcome the existing deficiencies of traditional recognition elements such as antibodies, aptamers. The integration of MMIPs as recognition elements with chemical sensors opens new opportunities for the development of advanced analytical devices with improved selectivity and sensitivity, shorter analysis time, and lower cost. Recently, MMIPs-chemical sensors (MMIPs-CS) have made significant progress in detection, but many challenges and development spaces remain. Therefore, this review focuses on the research progress of the sensor based on biomarker detection and introduces the surface modification of the magnetic support material used to prepare high selective MMIPs, as well as the selective extraction of target biomarkers by MMIPs from the complex biological sample matrix. Based on the understanding of optical sensors and electrochemical sensors, the applications of MMIPs-optical sensors (MMIPs-OS) and MMIPs-electrochemical sensors (MMIPs-ECS) for biomarker detection were reviewed and discussed in detail. Moreover, it provides an overview of the challenges in this research area and the potential strategies for the rational design of high-performance MMIPs-CS, accelerating the development of multifunctional MMIPs-CS.

Journey to the Market: The Evolution of Biodegradable Drug Delivery Systems

Biodegradable polymers have been used as carriers in drug delivery systems for more than four decades. Early work used crude natural materials for particle fabrication, whereas more recent work has utilized synthetic polymers. Applications include the macroscale, the microscale, and the nanoscale. Since pioneering work in the 1960’s, an array of products that use biodegradable polymers to encapsulate the desired drug payload have been approved for human use by international regulatory agencies. The commercial success of these products has led to further research in the field aimed at bringing forward new formulation types for improved delivery of various small molecule and biologic drugs. Here, we review recent advances in the development of these materials and we provide insight on their drug delivery application. We also address payload encapsulation and drug release mechanisms from biodegradable formulations and their application in approved therapeutic products.

Metal-Organic Frameworks and Their Composites Towards Biomedical Applications

Owing to their unique features, including high cargo loading, biodegradability, and tailorability, metal–organic frameworks (MOFs) and their composites have attracted increasing attention in various fields. In this review, application strategies of MOFs and their composites in nanomedicine with emphasis on their functions are presented, from drug delivery, therapeutic agents for different diseases, and imaging contrast agents to sensor nanoreactors. Applications of MOF derivatives in nanomedicine are also introduced. Besides, we summarize different functionalities related to MOFs, which include targeting strategy, biomimetic modification, responsive moieties, and other functional decorations. Finally, challenges and prospects are highlighted about MOFs in future applications.

Metal-Organic Frameworks for Bioimaging: Strategies and Challenges

Metal-organic frameworks (MOFs), composited with metal ions and organic linkers, have become promising candidates in the biomedical field own to their unique properties, such as high surface area, pore-volume, tunable pore size, and versatile functionalities. In this review, we introduce and summarize the synthesis and characterization methods of MOFs, and their bioimaging applications, including optical bioimaging, magnetic resonance imaging (MRI), computed tomography (CT), and multi-mode. Furthermore, their bioimaging strategies, remaining challenges and future directions are discussed and proposed. This review provides valuable references for the designing of molecular bioimaging probes based on MOFs.

Current status and future prospects of nanoscale metal–organic frameworks in bioimaging

The importance of diagnosis and in situ monitoring of lesion regions and transportation of bioactive molecules has a pivotal effect on successful treatment, reducing side effects, and increasing the chances of survival in the case of diseases.

A nanosized anionic MOF with rich thiadiazole groups for controlled oral drug delivery

Controlling the crystal size and surface chemistry of MOF materials, and understanding their multifunctional effect are of great significance for the biomedical applications of MOF systems. Herein, we designed and synthesized a new anionic MOF, ZJU-64-NSN, which features 1D channels decorated with highly polarized thiadiazole groups, and its crystal size could be systematically tuned from 200 ​μm to 300 ​nm through a green and simple approach. As a result, the optimal nanosized ZJU-64-NSN is found to enable an ultrafast loading of cationic drug procainamide (PA) (21.2 ​wt% within 1 ​min). Moreover, the undesirable chemical stability of PA@ZJU-64-NSN is greatly improved by the surface coating of polyethylene glycol (PEG) biopolymer. The final drug delivery system PEG/PA@ZJU-64-NSN is found to effectively prevent PA from premature release under the harsh stomach environments due to the intense host-guest interaction, and mainly release PA to the targeted intestinal surroundings. Such controlled drug delivery is proved to be triggered by endogenic Na⁺ ions instead of H⁺ ions, well revealed by the study on the dynamics behavior of drug release and UV–Vis absorption spectrum. Good biocompatibility of ZJU-64-NSN and PEG-coated ZJU-64-NSN has been fully demonstrated by MTT assay as well as confocal microscopy imaging.

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A new anionic MOF enables an ultrafast drug loading.

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The crystal size of such MOF could be well size-controlled.

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The surface coating of PEG improves the chemical stability of drug carrier.

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The drug delivery system reveals an endogenic Na ​⁺ ​-triggered procainamide release.

Construction of a Multifunctional Nano-Scale Metal-Organic Framework-Based Drug Delivery System for Targeted Cancer Therapy

The antitumor activity of triptolide (TP) has received widespread attention, although its toxicity severely limits its clinical application. Therefore, the design of a targeted drug delivery system (TDDS) has important application prospects in tumor treatment. Metal–organic frameworks (MOFs), with high drug-carrying capacity and good biocompatibility, have aroused widespread interest for drug delivery systems. Herein, folic acid (FA) and 5-carboxylic acid fluorescein (5-FAM) were used to modify Fe-MIL-101 to construct a functionalized nano-platform (5-FAM/FA/TP@Fe-MIL-101) for the targeted delivery of the anti-tumor drug triptolide and realize in vivo fluorescence imaging. Compared with Fe-MIL-101, functionalized nanoparticles not only showed better targeted therapy efficiency, but also reduced the systemic toxicity of triptolide. In addition, the modification of 5-FAM facilitated fluorescence imaging of the tumor site and realized the construction of an integrated nano-platform for fluorescence imaging and treatment. Both in vitro and in vivo studies of functionalized nanoparticles have demonstrated excellent fluorescence imaging and synergistic targeting anticancer activity with negligible systemic toxicity. The development of functional nano-platform provides new ideas for the design of MOF-based multifunctional nano-drug delivery system, which can be used for precise treatment of tumor.

PEGylated Nanoscale Metal-Organic Frameworks for Targeted Cancer Imaging and Drug Delivery

Nanoscale metal-organic frameworks (nMOFs) are a unique type of hybrid materials, which are broadly applicable as cargo delivery systems. However, the relatively low material stability and insufficient cancer cell interacting capacity have limited nMOFs' applications in cancer theranostics. Herein, a zirconium-based nMOF UiO-66-N₃ was synthesized, and its surface was covalently functionalized with alkyne-containing polyethylene glycol (PEG) via the azide-alkyne click chemistry. After that, F3 peptide was attached for targeting of cancer cells (the material was denoted as UiO-66-PEG-F3). Doxorubicin (DOX) served as a therapeutic drug and a fluorescent label in this study, and it was transported into UiO-66-PEG conjugates with sufficient drug loading efficiency. pH-responsive release of DOX from UiO-66 conjugates was witnessed. The structural integrity of UiO-66-N₃ was maintained post the surface modification process. Flow cytometry and confocal fluorescence microscopy revealed that DOX/UiO-66-PEG-F3 had stronger accumulation in MDA-MB-231 cells (nucleolin⁺) compared with DOX/UiO-66-PEG. In order to track the pharmacokinetic behavior (organ distribution profile) in vivo, the positron-emitting zirconium-89 (⁸⁹Zr) was incorporated into UiO-66-N₃. Similar PEGylation and F3 peptide conjugation resulted in the formation of ⁸⁹Zr-UiO-66-PEG-F3. Serial positron emission tomography (PET) imaging demonstrated that the preferential accumulation of ⁸⁹Zr-UiO-66-PEG-F3 in MDA-MB-231 tumors, and their liver clearance was faster than PEGylated UiO-66 using noncovalent methods. Thus, the PEGylated nMOFs using covalent strategies may find broad application in future cancer theranostics.

Dual-ligated metal organic framework as novel multifunctional nanovehicle for targeted drug delivery for hepatic cancer treatment

In the last decade, nanosized metal organic frameworks (NMOFs) have gained an increasing applicability as multifunctional nanocarriers for drug delivery in cancer therapy. However, only a limited number of platforms have been reported that can serve as an effective targeted drug delivery system (DDSs). Herein, we report rational design and construction of doxorubicin (DOX)-loaded nanoscale Zr (IV)-based NMOF (NH2-UiO-66) decorated with active tumor targeting moieties; folic acid (FA), lactobionic acid (LA), glycyrrhetinic acid (GA), and dual ligands of LA and GA, as efficient multifunctional DDSs for hepatocellular carcinoma (HCC) therapy. The success of modification was exhaustively validated by various structural, thermal and microscopic techniques. Biocompatibility studies indicated the safety of pristine NH2-UiO-66 against HSF cells whereas DOX-loaded dual-ligated NMOF was found to possess superior cytotoxicity against HepG2 cells which was further confirmed by flow cytometry. Moreover, fluorescence microscopy was used for monitoring cellular uptake in comparison to the non-ligated and mono-ligated NMOF. Additionally, the newly developed dual-ligated NMOF depicted a pH-responsiveness towards the DOX release. These findings open new avenues in designing various NMOF-based DDSs that actively target hepatic cancer to achieve precise therapy.

Nanoscale Metal-Organic Frameworks: Recent developments in synthesis, modifications and bioimaging applications

Porous Metal-Organic Frameworks (MOFs) have emerged as eye-catching materials in recent years. They are widely used in numerous fields of chemistry thanks to their desirable properties. MOFs have a key role in the development of bioimaging platforms that are hopefully expected to effectually pave the way for accurate and selective detection and diagnosis of abnormalities. Recently, many types of MOFs have been employed for detection of RNA, DNA, enzyme activity and small-biomolecules, as well as for magnetic resonance imaging (MRI) and computed tomography (CT), which are valuable methods for clinical analysis. The optimal performance of the MOF in the bio-imaging field depends on the core structure, synthesis method and modifications processes. In this review, we have attempted to present crucial parameters for designing and achieving an efficient MOF as bioimaging platforms, and provide a roadmap for researchers in this field. Moreover, the influence of modifications/fractionalizations on MOFs performance has been thoroughly discussed and challenging problems have been extensively addressed. Consideration is mainly focused on the principal concepts and applications that have been achieved to modify and synthesize advanced MOFs for future applications.

Nanosized biligated metal-organic framework systems for enhanced cellular and mitochondrial sequential targeting of hepatic carcinoma

Mitochondria are reported to play a paramount role in tumorigenesis which positions them as an instrumental druggable target. However, selective drug delivery to cancer-localized mitochondria remains challenging. Herein, we report for the first time, the design, development and evaluation of a hepatic cancer-specific mitochondria-targeted dual ligated nanoscale metal-organic framework (NMOF) for cellular and mitochondrial sequential drug delivery. Surface functionalization was performed through covalent-linking of folic acid and triphenylphosphonium moieties to the aminated Zr-based MOF, NH₂-UiO-66. The characterization of the dual-ligated NMOFs using XRD, FTIR, DSC and BET analysis proved the successful conjugation process. Assessment of the drug loading and release profiling of doxorubicin (DOX)-loaded NMOF confirmed the proper retention of the drug within the NMOF porous structure alongside enhanced release in the tumor acidic environment. Furthermore, biological evaluation of the anti-tumor activity of the DOX-loaded dual-ligated NMOF on hepatocellular carcinoma affirmed the superiority of the developed system in killing the cancerous cells via apoptosis induction and halting cell cycle progression. This study attempts to underscore the promising potential of surface functionalized NMOFs in developing anticancer drug delivery systems to achieve targeted therapy.

Fenton Reaction Induced by Fe-Based Nanoparticles for Tumor Therapy

Fenton reaction, a typical inorganic reaction, is broadly utilized in the field of wastewater treatment. Recently In case of its ability to inhibit the growth of cancer cells, it has been frequently reported in cancer treatment. Using the unique tumor microenvironment in cancer cells, many iron-based nanoparticles have been developed to release iron ions in cancer cells to induce Fenton reaction. In this mini review, we outline several different types of iron-based nanoparticles and several main means to enhance Fenton reaction in cancer cells. Finally, we discussed the advantages and disadvantages of iron-based nanoparticles for cancer therapy, prospected the future development of iron-based nanoparticles. It is believed that iron-based nanoparticles can make certain contribution to the cause of human cancer in the future.

Design of metal-organic framework composites in anti-cancer therapies

Metal-organic frameworks are a class of new and promising anti-cancer materials. MOFs with adjustable pore size, large specific surface area, diverse structure, and excellent chemical and physical properties make them a class of effective protection carriers for anti-cancer substances. This review is centered on the core point of "anti-cancer" and discusses MOFs' research progress in anti-cancer therapies. Firstly, we provided readers with the different types of MOFs, their preparation strategies and the resulting structures. Then, different MOF composites and their biological applications were systematically presented. The specificity of biomolecules endows MOFs with broader anti-cancer applications, while MOFs can protect the drugs and biomolecules to make the best of a challenging situation. Finally, we elucidated a comprehensive overview of the biological applications of MOFs, including research hotspots as drug delivery and biomolecule carriers. Besides, we looked forward to the future developments of MOFs in the field of anti-cancer therapies. As a class of novel materials, the anti-cancer applications of MOFs are extended through the combination of different materials and different methods to improve their efficacy.

Naphthalimide Derivative-Functionalized Metal-Organic Framework for Highly Sensitive and Selective Determination of Aldehyde by Space Confinement-Induced Sensitivity Enhancement Effect

Facile and sensitive determination of formaldehyde (FA) in indoor environments still remains challenging. Herein, a fluorescent probe, termed PHN@MOF, was synthesized by embedding the fluorescent molecule of N-propyl-4-hydrazine-naphthalimide (PHN) into a metal-organic framework (MOF) for sensitive and visual monitoring of FA. The hydrazine group of PHN acts as the specific reaction group with FA based on the condensation reaction. The host of MOF (UiO-66-NH₂) offers the surrounding confinement space required for the reaction. Owing to the enrichment effect and molecular sieve selection of UiO-66-NH₂ to FA, PHN@MOF, compared with free PHN, exhibits very high sensitivity and selectivity based on space confinement-induced sensitivity enhancement (SCISE). Moreover, the fluorescence of UiO-66-NH₂ offers a reference signal for FA detection. Using this ratiometric fluorescent PHN@MOF probe, a colorimetric gel plate and test paper were developed and used to visually monitor FA in air.

Delivery of oxaliplatin to colorectal cancer cells by folate-targeted UiO-66-NH2

Oxaliplatin is being used in different malignancies and several side effects are reported for patients taking Oxaliplatin, including peripheral neuropathy, nausea and vomiting, diarrhea, mouth sores, low blood counts, fatigue, loss of appetite, etc. Here we have developed a targeted anticancer drug delivery system based on folate-conjugated amine-functionalized UiO-66 for the delivery of oxaliplatin (OX). UiO-66-NH₂ (U) and UiO-66-NH₂-FA(FU) were pre-functionalized by the incorporation of folic acid (FA) into the structure via coordination of the carboxylate group of FA. The FTIR spectra of drug-loaded U and FU showed the presence of new carboxylic and aliphatic groups of OX and FA. Powder X-ray diffraction (PXRD) patterns were matched accordingly with the reference pattern and FESEM results showed semi-spherical particles (115-128 nm). The evaluated amounts of OX in U and FU were calculated 304.5 and 293 mg/g_, respectively. The initial burst release of OX was 15.7% per hour for U(OX) and 10.8% per hour for FU(OX). The final release plateau gives 62.9% and 52.3% for U(OX) and FU(OX). To evaluate the application of the prepared delivery platform, they were tested on colorectal cancer cells (CT-26) via MTT assay, cell migration assay, and spheroid model. IC₅₀ values obtained from MTT assay were 21.38, 95.50, and 18.20 μg/mL for OX, U(OX), and FU(OX), respectively. After three days of treatment, the CT26 spheroids at two doses of 500 and 50 μg/mL of U(OX) and FU(OX) showed volume reduction. Moreover, the oxidative behavior of the prepared systems within the cell was assessed by total thiol, malondialdehyde, and superoxide dismutase activity. The results showed that FU(OX) had higher efficacy in preventing the growth of CT-26 spheroid, and was more effective than oxaliplation in cell migration inhibition, and induced higher oxidative stress and apoptosis.

Detection of sialic acid using boronic-acid-functionalized metal organic framework UiO-66-NH2@B(OH)2

Sialic acid (SA) is a crucial component of glycoproteins and glycolipids on the cellular membrane, which is essential for maintaining the function of cell membranes, such as cell recognition and communication. Simultaneously, sialic acid plays a significant role in many physiological and pathological processes. Hence, it is urgent to develop a simple and sensitive strategy for determining sialic acid. In this work, a new metal-organic framework called UiO-66-NH₂@B(OH)₂ has been designed and synthesized for the recognition and detection of sialic acid. The boronic acid functional group in UiO-66-NH₂@B(OH)₂ can bind to a diol moiety of the glycerol side chain of sialic acid, which will attenuate or even quench the fluorescence of UiO-66-NH₂@B(OH)₂, thus opening a new road to detect sialic acid. Based on the measurement results, sialic acid can be quantitatively measured in a linear range of 0.05-2.5 mmoL/L with the UiO-66-NH₂@B(OH)₂ probe. The detection limit of sialic acid is as low as 0.025 mmol/L. Furthermore, the boronic-acid functionalized probe UiO-66-NH₂@B(OH)₂ displays high sensitivity and high selectivity to recognize the sialic acid in mouse serum samples. Therefore, the developed UiO-66-NH₂@B(OH)₂ can be used as a promising probe to identify and detect sialic acid in the practical application.

An investigation of affecting factors on MOF characteristics for biomedical applications: A systematic review

Metal-organic frameworks (MOFs) are a fascinating class of crystalline porous materials composed of metal ions and organic ligands. Due to their attractive properties, MOFs can potentially offer biomedical field applications, such as drug delivery and imaging. This study aimed to systematically identify the affecting factors on the MOF characteristics and their effects on structural and biological characteristics. An electronic search was performed in four databases containing PubMed, Scopus, Web of Science, and Embase, using the relevant keywords. After analyzing the studies, 20 eligible studies were included in this review. As a result, various factors such as additives and organic ligand can influence the size and structure of MOFs. Additives are materials that can compete with ligand and may affect the nucleation and growth processes and, consequently, particle size. The nature and structure of ligand are influential in determining the size and structure of MOF. Moreover, synthesis parameters like the reaction time and initial reagents ratio are critical factors that should be optimized to regulate the size and structure. Of note is that the nature of the ligand and using a suitable additive can control the porosity of MOF. The more extended ligands aid in forming large pores. The choice of metallic nodes and organic ligand, and the MOF concentration are important factors since they can determine toxicity and biocompatibility of the final structure. The physicochemical properties of MOFs, such as hydrophobicity, affect the toxicity of nanoparticles. An increase in hydrophobicity causes increased toxicity of MOF. The biodegradability of MOF, as another property, depends on the organic ligand and metal ion and environmental conditions like pH. Photocleavable ligands can be served for controlled degradation of MOFs. Generally, by optimizing these affecting factors, MOFs with desirable properties will be obtained for biomedical applications.

A novel route to size-controlled MIL-53(Fe) metal-organic frameworks for combined chemodynamic therapy and chemotherapy for cancer

Metal-organic frameworks (MOFs), such as MIL-53(Fe), have considerable potential as drug carriers in cancer treatment due to their notable characteristics, including controllable particle sizes, high catalytic activity, biocompatibility and large porosity, and are widely used in a broad range of drugs. In this study, a new approach for the synthesis of MIL-53(Fe) nanocrystals with controlled sizes has been developed using a non-ionic surfactant PVP as the conditioning and stabilizing agent, respectively. During the nucleation of MIL-53(Fe), the PVP droplet, as a nano-reactor, controlled the growth of the crystal nucleus. The size and aspect ratio (length/width) of nanocrystals increased with an increase in PVP in the synthetic mixture. The MIL-53(Fe) nanocrystals showed a homogeneous morphology, with approximately 190 nm in length and 100 nm in width. MIL-53(Fe) not only was used to load the anticancer drug doxorubicin (DOX) but also generated hydroxyl radicals (˙OH) via a Fenton-like reaction for ROS-mediated/chemo-therapy of cancer cells. The approach was expected to synthesize numerous types of nano-size iron(iii)-based MOFs, such as MIL-53, 89, 88A, 88B and 101. The MIL-53(Fe) nanocrystals hold great promise as a candidate to improve the controlled release of drugs and treatment effect for cancer therapy.

A novel fluorescent strategy based on double modifications of metal organic framework material CAU-10-NH2 for low background and high sensitivity determination of H2S

Hydrogen sulfide is typical metabolic marker and environmental pollutant which is worthwhile to determine. Herein, a low background and high sensitivity fluorescent strategy based on double modifications of metal organic framework material CAU-10-NH₂ is proposed for the determination of hydrogen sulfide. Firstly, a functional monomer 3,5-diaminobenzoic acid is employed to modify on the CAU-10-NH₂, the product CAU-10-NH-dAba has strong fluorescent performance at 412 nm under an excitation wavelength of 320 nm. Subsequently, it is further modified by the azide group to form CAU-10-NH-dAba-N₃. This azidation inhibits the fluorescent signal. However, in the presence of hydrogen sulfide, the azide group is specifically reduced to amidogen, and results in the recovery of the fluorescence. The CAU-10-NH-DABA-N₃ was characterized by solid state NMR, XPS, fluorescence, IR, XRD, SEM and specific surface area. After the optimization of pH value, temperature and interaction time, the detection results of hydrogen sulfide demonstrate the linear range of this strategy is from 20 to 140 nM with a detection limit of 1.51 nM, which is significantly better than that of the CAU-10-NH₂ merely modified by 3,5-dinitrobenzoic acid. Meanwhile, the satisfactory assay results of hydrogen sulfide in serum sample and Pearl river water suggest a potential application prospect of this strategy in clinical diagnosis and environment monitoring.

Designed Tb(III)-Functionalized MOF-808 as Visible Fluorescent Probes for Monitoring Bilirubin and Identifying Fingerprints

Abnormal bilirubin (BR) level is a sign of several fatal diseases, so it is of great significance and challenge to develop a facile and effective family routine strategy for BR sensing. Herein, novel water-stable Tb³⁺@MOF-808 has been synthesized using a coordinated postsynthetic modification strategy and designed as a convenient and efficient fluorescence probe. The fabricated fluorescent probe exhibits a remarkable fluorescence quenching effect with the successive addition of BR, which displays fascinating features, such as fast response time, high sensitivity, and excellent selectivity. The quenching mechanism between the fluorescent probe and BR was also illustrated in detail. Importantly, the devised fluorescent probe successfully achieved the determination of BR in serum and urine, which has also been successfully used in the design of portable BR test paper. The developed monitoring platform for BR levels in vivo provides promising application potential for the prevention and early diagnosis of fatal diseases. Additionally, a molecular logic gate device that performs intelligent fluorescent sensing of BR was constructed. More interestingly, Tb³⁺@MOF-808 is used for development of latent fingerprints on different guest surfaces. The lines of the fluorescent fingerprints are clear and coherent, the details are obvious, and even sweat pores can be observed by naked eyes, which provides new means for tracking the criminal clue and handling cases efficiently.

Water Photo-Electrooxidation Using Mats of TiO2 Nanorods, Surface Sensitized by a Metal–Organic Framework of Nickel and 1,2-Benzene Dicarboxylic Acid

Photoanodes comprising a transparent glass substrate coated with a thin conductive film of fluorine-doped tin oxide (FTO) and a thin layer of a photoactive phase have been fabricated and tested with regard to the photo-electro-oxidation of water into molecular oxygen. The photoactive layer was made of a mat of TiO2 nanorods (TDNRs) of micrometric thickness. Individual nanorods were successfully photosensitized with nanoparticles of a metal–organic framework (MOF) of nickel and 1,2-benzene dicarboxylic acid (BDCA). Detailed microstructural information was obtained from SEM and TEM analysis. The chemical composition of the active layer was determined by XRD, XPS and FTIR analysis. Optical properties were determined by UV–Vis spectroscopy. The water photooxidation activity was evaluated by linear sweep voltammetry and the robustness was assessed by chrono-amperometry. The OER (oxygen evolution reaction) photo-activity of these photoelectrodes was found to be directly related to the amount of MOF deposited on the TiO2 nanorods, and was therefore maximized by adjusting the MOF content. The microscopic reaction mechanism which controls the photoactivity of these photoelectrodes was analyzed by photo-electrochemical impedance spectroscopy. Microscopic rate parameters are reported. These results contribute to the development and characterization of MOF-sensitized OER photoanodes.

Outstanding Drug-Loading/Release Capacity of Hollow Fe-Metal-Organic Framework-Based Microcapsules: A Potential Multifunctional Drug-Delivery Platform

Owing to their characteristic structures, metal-organic frameworks (MOFs) are considered as the leading candidate for drug-delivery materials. However, controlling the synthesis of MOFs with uniform morphology and high drug-loading/release efficiencies is still challenging, which greatly limits their applications and promotion. Herein, a multifunctional MOF-based drug-delivery system (DDS) with a controlled pore size of 100-200 nm for both therapeutic and bioimaging purposes was successfully synthesized in one step. Fe-MOF-based microcapsules were synthesized through a competitive coordination method, which was profited from the intrinsic coordination characteristics of the Fe element and the host-guest supramolecular interactions between Fe³⁺ and polyoxometalates anions. This as-synthesized macroporous DDS could greatly increase the drug-loading/release rate (77%; 83%) and serve as a magnetic resonance (MR) contrast agent. Because an Fe-containing macroporous DDS presents ultrahigh drug loading/release, the obtained 5-FU/Fe-MOF-based microcapsules displayed good biocompatibility, extremely powerful inhibition of tumor growth, and satisfactory MR imaging capability. Given all these advantages, this study integrates high therapeutic effect and diagnostic capability via a simple and effective morphology-controlling strategy, aiming at further facilitating the applications of MOFs in multifunctional drug delivery.

Multifunctional metal-organic framework heterostructures for enhanced cancer therapy

Metal-organic frameworks (MOFs) are an emerging class of molecular crystalline materials built from metal ions or clusters bridged by organic linkers. By taking advantage of their synthetic tunability and structural regularity, MOFs can hierarchically integrate nanoparticles and/or biomolecules into a single framework to enable multifunctions. The MOF-protected heterostructures not only enhance the catalytic capacity of nanoparticle components but also retain the biological activity of biomolecules in an intracellular microenvironment. Therefore, the multifunctional MOF heterostructures have great advantages over single components in cancer therapy. In this review, we comprehensively summarize the general principle of the design and functional modulation of nanoscaled MOF heterostructures, and biomedical applications in enhanced therapy within the last five years. The functions of MOF heterostructures with a controlled size can be regulated by designing various functional ligands and in situ growth/postmodification of nanoparticles and/or biomolecules. The advances in the application of multifunctional MOF heterostructures are also explored for enhanced cancer therapies involving photodynamic therapy, photothermal therapy, chemotherapy, radiotherapy, immunotherapy, and theranostics. The remaining challenges and future opportunities in this field, in terms of precisely localized assembly, maximizing composite properties, and processing new techniques, are also presented. The introduction of multiple components into one crystalline MOF provides a promising approach to design all-in-one theranostics in clinical treatments.

A versatile and multifunctional metal-organic framework nanocomposite toward chemo-photodynamic therapy

Previously most of the applications of targeting components have been based on the enhanced permeability and retention effect achieved using folic acid, which consider the side effects of the targeting components to some extent. Herein, we report a new strategy to decorate the surface of MOFs using a pemetrexed (MTA) targeting molecule, affording a new drug delivery system of ALA@UIO-66-NH-FAM/MTA (ALA = 5-amino-levulinic acid and FAM = 5-carboxyfluorescein). The confocal microscopy and flow cytometry results showed that ALA@UIO-66-NH-FAM/MTA presented a better targeting effect compared to ALA@UIO-66-NH-FAM/FA (FA = folic acid) and indicated a gradually increasing tendency of the targeting effect with the increasing expression of folate receptors on the tumor cell cytomembrane. Furthermore, the cytotoxicity experiment indicates that the combination of chemotherapy and photodynamic therapy is a more effective therapy model than single chemotherapy and photodynamic therapy. This work demonstrates the first attempt at folic acid antagonist (MTA) modification for NMOFs, providing a new concept for the design of MOFs with folate receptor targeting capacity for clinical applications.

Highly selective detection of Cu2+ in aqueous media based on Tb3+-functionalized metal-organic framework

In this work, a metal-organic framework UiO-66-(COOH)₂ has been synthesized and is further functionalized with Tb³⁺ through coordination interactions. The functionalized MOF, denoted as Tb³⁺@UiO-66-(COOH)₂, is fully characterized and further developed as an excellent fluorescent probe to monitor Cu²⁺ ions in aqueous media by fluorescence quenching effect. Tb³⁺@UiO-66-(COOH)₂ exhibits high selectivity and sensitivity, broad linear concentration range (0-200 μM), low detection limits (0.23 μM), fast response speed (within 1 min), as well as in situ naked eye observation under UV light for sensing Cu²⁺ ion. Furthermore, this probe was successfully employed to detect Cu²⁺ ion in real water with good recovery. Hence, this work developed a very excellent fluorescent sensor with high potential practical applications for detection of Cu²⁺ ion in environmental water samples.