Synergistic cancer treatment using porphyrin-based metal-organic Frameworks for photodynamic and photothermal therapy

Recent advancements in multifunctional nanomaterials for cancer therapy have highlighted porphyrin-based metal-organic frameworks (MOFs) as promising candidates due to their unique properties and versatile applications. This overview focuses on the use of porphyrin-based MOFs for combined photodynamic therapy (PDT) and photothermal therapy (PTT) in cancer treatment. Porphyrin-based MOFs offer high porosity, tuneable structures, and excellent stability, making them ideal for drug delivery and therapeutic applications. The incorporation of porphyrin molecules into the MOF framework enhances light absorption and energy transfer, leading to improved photodynamic and photothermal effects. Additionally, the porosity of MOFs allows for the encapsulation of therapeutic agents, further enhancing efficacy. In PDT, porphyrin-based MOFs generate reactive oxygen species (ROS) upon light activation, destroying cancer cells. The photothermal properties enable the conversion of light energy into heat, resulting in localised hyperthermia and tumour ablation. The combination of PDT and PTT in a single platform offers synergistic effects, leading to better therapeutic outcomes, reduced side effects, and improved selectivity. This dual-modal treatment strategy provides precise spatiotemporal control over the treatment process, paving the way for next-generation therapeutics with enhanced efficacy and reduced side effects. Further research and optimisation are needed for clinical applications.

Two-dimensional metal-organic frameworks (2D-MOFs) as a carrier for enzyme immobilization: A review on design and bio-applications

In the realm of carriers for enzyme immobilization, the use of MOFs has accelerated owing to their exceptional porosity and stability. Among these, 2D metal-organic frameworks (2D-MOFs) have emerged as promising supports for enzyme immobilization. This review highlights advancements in their synthesis, structural properties, and functional characteristics, focusing on enhancing catalytic performance and stability. Brief insights into computational approaches for optimizing these nanostructures and their catalytic efficiency are provided. The unique synergy between 2D MOF-based nanozymes and enzymes is discussed, showcasing their potential in diverse applications. Challenges in their practical implementation, prospective solutions, and future research directions are also outlined. This review emphasizes the transformative potential of 2D MOFs, focusing on their design and bioapplications and paving the way for innovative and sustainable strategies.

Two-dimensional metal organic frameworks in cancer treatment

With large specific surface area, controllable pore size, increased active sites, and structural stability, two-dimensional metal organic frameworks (2D MOFs) have emerged as promising nanomedicines in cancer therapy. These distinctive features make 2D MOFs particularly advantageous in cancer treatment and the corresponding application has gained considerable popularity, signifying significant application potential. Herein, recent advances in various applications including drug delivery and chemotherapy, photodynamic therapy, sonodynamic therapy, chemodynamic therapy, catalytic therapy, and combined therapy were summarized, with emphasis on the latest progress of new materials and mechanisms for these processes. Moreover, the current challenges, potential solutions, and possible future directions are discussed as well.

Luminescent lanthanide-based molecular materials: applications in photodynamic therapy

Luminescent lanthanide molecular compounds have recently attracted attention as potential photosensitizers (PSs) for photodynamic therapy (PDT) against malignant cancer tumours because of their predictable systemic toxicity, temporospatial specificity, and minimal invasiveness. A photosensitizer exhibits no toxicity by itself, but in the presence of light and oxygen molecules, it can generate reactive oxygen species (ROS) to cause damage to proteins, nucleic acids, lipids, membranes, and organelles, which can induce cell apoptosis. This review focuses on the latest developments in luminescent lanthanide-based molecular materials as photosensitizers and their applications in photodynamic therapy. These molecular materials include lanthanide coordination complexes, nanoscale lanthanide coordination polymers, and lanthanide-based nanoscale metal-organic frameworks. In the end, the future challenges in the development of robust luminescent lanthanide molecular materials-based photosensitisers are outlined and emphasized to inspire the design of a new generation of phototheranostic agents.

Sunlight-Driven Photocatalysis for a Set of 3D Metal-Porphyrin Frameworks Based on a Planar Tetracarboxylic Ligand and Lanthanide Ions

Metal-porphyrin frameworks (MPFs) with trivalent lanthanide ions are the most sought-after materials in the past decade. Their porosities are usually complemented by optical properties imparted by the metal nodes, making them attractive multifunctional materials. Here, we report a novel family of 3D MPFs obtained through solvothermal reactions between tetrakis(4-carboxyphenyl) porphyrin (H4TCPP) and different lanthanide sources, yielding an isostructural family of compounds along the lanthanide series: [Ln2(DMF)(TCPP)1.5] for Ln = La, Ce, Nd, Pr, Er, Y, Tb, Dy, Sm, Eu, Gd, and Tm. Photoluminescent properties of selected phases were explored at room temperature. Also, the photocatalytic performance exhibited by these compounds under sunlight exposure is promising for its implementation in organic pollutant degradation. In order to study the photocatalytic activity of Ln-TCPPs in an aqueous medium, methylene blue (MB) was used as a contaminant model. The efficiency for MB degradation was Sm > Y > Yb > Gd > Er > Eu > either no catalyst or no light, obtaining more than 70% degradation at 120 min with Sm-TCPP. These results open the possibility of using these compounds in optical and optoelectronic devices for water remediation and sensing.

Lanthanide-based MOFs: synthesis approaches and applications in cancer diagnosis and therapy

Metal-organic frameworks (MOFs) have attracted considerable attention as emerging nanomaterials. Based on their tunable size, high porosity, and large specific surface area, MOFs have a wide range of applications in the fields of chemistry, energy, and biomedicine. However, the MOF materials obtained from lanthanides with a unique electronic configuration as inorganic building units have unique properties such as optics, magnetism, and radioactivity. In this study, various synthetic methods for preparing MOF materials using lanthanides as inorganic building units are described. Combined with the characteristics of lanthanides, their application prospects of lanthanide-based MOFs in tumor diagnosis and treatment are emphasized. The authors hope to provide methodological reference for the construction of MOF materials of rare-earth elements, and to provide ideas and inspiration for their practical applications in the field of biomedicine.

Photo- and radio-luminescence of porphyrin functionalized ZnO/SiO2 nanoparticles

The development of hybrid nanoscintillators is hunted for the implementation of modern detection technologies, like in high energy physics, homeland security, radioactive gas sensing, and medical imaging, as well as of the established therapies in radiation oncology, such as in X-ray activated photodynamic therapy. Engineering of the physico-chemical properties of nanoparticles (NPs) enables the manufacture of hybrids in which the conjugation of inorganic/organic components leads to increased multifunctionality and performance. However, the optimization of the properties of nanoparticles in combination with the use of ionizing radiation is not trivial: a complete knowledge on the structure, composition, physico-chemical features, and scintillation property relationships in hybrid nanomaterials is pivotal for any applications exploiting X-rays. In this paper, the design of hybrid nanoscintillators based on ZnO grown onto porous SiO₂ substrates (ZnO/SiO₂) has been performed in the view to create nanosystems potentially suitable in X-ray activated photodynamic therapy. Indeed, cytotoxic porphyrin dyes with increasing concentrations have been anchored on ZnO/SiO₂ nanoparticles through amino-silane moieties. Chemical and structural analyses correlated with photoluminescence reveal that radiative energy transfer between ZnO and porphyrins is the principal mechanism prompting the excitation of photosensitizers. The use of soft X-ray excitation results in a further sensitization of the porphyrin emission, due to augmented energy deposition promoted by ZnO in the surroundings of the chemically bound porphyrin. This finding unveils the cruciality of the design of hybrid nanoparticles in ruling the efficacy of the interaction between ionizing radiation and inorganic/organic moieties, and thus of the final nanomaterial performances towards the foreseen application.

Morphologically Flex Sm-MOF Based Electrochemical Immunosensor for Ultrasensitive Detection of a Colon Cancer Biomarker

Despite having the potential to synthesize stable metal-organic frameworks (MOFs), rare earth metal-based MOFs have not been exploited extensively. Owing to the high coordination numbers, the MOFs can generate a suitable coordination environment for various applications. Herein, samarium (Sm)-based MOFs were synthesized with three different organic linkers, namely, trimesic acid (TMA), meso-tetra(4-carboxyphenyl)porphine (TCPP), and 1,3,6,8-tetra(4-carboxylphenyl) pyrene(TBPy) by the solvothermal approach. The morphologies of Sm-TMA MOF, Sm-TCPP MOF, Sm-TBPy MOF were rod-shaped, cubic consisting of stacked 2D layers, and spherical made of small cubic structures, respectively. After the electrochemical properties of the synthesized MOFs were investigated, the MOFs were used to fabricate immunosensors for detection of carcinoembryonic antigen using a label-free signaling strategy. The immunosensors exhibited a wide linear detection range and a lower detection limit. The exhibited reproducibility and selectivity of the immunosensors were within the tolerable limits. The established label-free immunosensor has been successfully applied for detection of carcinoembryonic antigen in human serum samples, demonstrating that the rare earth metal-based MOFs are promising for construction of biosensors for medical diagnosis.

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.

Photosensitizer-based metal-organic frameworks for highly effective photodynamic therapy

Photodynamic therapy (PDT) uses a photosensitizer, molecular oxygen, and visible light as an alternative clinical protocol against located malignant tumors and other diseases. More recently, PDT has been combined to immunotherapy as a promising option to treat metastatic cancer. However, previous generations of photosensitizers (PSs) revealed clinical difficulties such as long-term skin photosensitivity (first generation), the need for drug delivery vehicles (second generation), and intracellular self-aggregation (third generation), which have generated a somewhat confusing scenario in PDT approaches and evolution. Recently, metal-organic frameworks (MOFs) with exceptionally high PS loading as a building unit of MOF framework have emerged as fourth-generation PS and presented outstanding outcomes under pre-clinical studies. For PS-based MOFs, the inorganic building unit (metal ions/clusters) plays an important role as a coadjuvant in PDT to alleviate hypoxia, to decrease antioxidant species, to yield ROS, or to act as a contrast agent for imaging-guided therapy. In this review, we intend to carry out a broad update on the recent history and the characteristics of PS-based MOFs from basic chemistry to the structure relationship with biological application in PDT. The details and variables that result in different photophysics, size, and morphology, are discussed. Also, we present an overview of the achievements on the pre-clinical assays in combination with other strategies, including alleviating hypoxia in solid tumors, chemotherapy, and the most recent immunotherapy for cancer.

2D materials for bone therapy

Due to their prominent physicochemical properties, 2D materials are broadly applied in biomedicine. Currently, 2D materials have achieved great success in treating many diseases such as cancer and tissue engineering as well as bone therapy. Based on their different characteristics, 2D materials could function in various ways in different bone diseases. Herein, the application of 2D materials in bone tissue engineering, joint lubrication, infection of orthopedic implants, bone tumors, and osteoarthritis are firstly reviewed comprehensively together. Meanwhile, different mechanisms by which 2D materials function in each disease reviewed below are also reviewed in detail, which in turn reveals the versatile functions and application of 2D materials. At last, the outlook on how to further broaden applications of 2D materials in bone therapies based on their excellent properties is also discussed.

ROS-generating rare-earth coordination networks for photodynamic inactivation of Candida albicans

Water-ethanol suspensions of 2D coordination network (CN) based on rare earth elements and mixed ligands were evaluated as reactive oxygen species (ROS) generators under UV light irradiation, in contact with a biomimetic substrate (tryptophan) or an O2(1Δg) quencher (1,3-diphenylisobenzofuran; 1,3-DPBF). A combination of bottom-up and top-down strategies was implemented in order to obtain nano-sized CN particles and the subsequent colloidal suspensions were also tested towards photodynamic inactivation of Candida albicans (C. albicans). SEM, TEM, FTIR, and XRD techniques were applied to characterize the solids and ICP-AES was employed to determine the metal content of the colloidal suspensions. Promising results were found indicating that the presence of Tb3+ allows an intersystem crossing suitable for singlet oxygen generation, resulting in the antifungal activity of C. albicans culture upon UV-irradiation.

The potential of photodynamic therapy in current breast cancer treatment methodologies

Photodynamic Therapy (PDT) has been known for over a hundred years, and currently gaining in acceptance as an alternative cancer treatment. Light delivery is still a difficult problem in deep cancer treatment with PDT. Only near-infrared light in the 700-1100 nm range can penetrate deeply into the tissue because most tissue chromophores, including oxyhemoglobin, deoxyhemoglobin, melanin and fat, poorly absorb in the near infrared window. The light sources used in PDT are lasers, arc lamps, light-emitting diodes and fluorescent lamps. PDT has been used for many different clinical applications. PDT may be excellent alternative in the treatment and diagnosis of breast cancer compared to the conventional surgery, chemotherapy and radiotherapy. The basic elements of PDT are an appropriate photosensitizer (PS), oxygen, and light. The effectiveness of photodynamic therapy depends on the induction of photocytotoxic reactions, which are the result of light activation of PS), pre-administered to the body. The condition for initiating PDT processes is light absorption by PS and subsequent localized generation of cytotoxic reactive oxygen species. This study is a review of empirical research aimed at improving the therapy and diagnosis of breast cancer using PDT based on the physicochemical differences in healthy and diseased tissues and the tissues undergoing treatment.

A CD44-targeted Cu(ii) delivery 2D nanoplatform for sensitized disulfiram chemotherapy to triple-negative breast cancer

Recent studies have suggested that the anticancer activity of disulfiram (DSF, an FDA-approved alcohol-abuse drug) is Cu-dependent. Low system toxicity and explicit pharmacokinetic characteristics of DSF necessitate safe and effective Cu supplementation in local lesion for further applications. Herein, we presented a new conceptual 'nanosized coordination transport' strategy of Cu(ii) that was realized in porphyrin-based metal-organic frameworks, Sm-TCPP, with strong binding ability to Cu(ii) due to their coordination interactions. Sm-TCPP(Cu) was coated by hyaluronic acid (HA) that termed by Sm-TCPP(Cu)@HA, acting as 'beneficial horse' to target the tumor-localized HA receptor (CD44), thus liberating Cu(ii) ions in cellular overexpressed reductants. The CD44-mediated Cu(ii) accumulation efficiency of Sm-TCPP(Cu)@HA was benchmarked in vitro and vivo against the free TCPP (Cu) via ICP-MS analysis. More importantly, the sensitization effects of Sm-TCPP(Cu)@HA on the anticancer activity of DSF were demonstrated in vivo and in vitro. This study offered a new class of targeted Cu supplements to sensitize DSF for the effective treatment of cancer and established a versatile methodology for constructing a safe and specific delivery of metal ions within living organisms.

A novel versatile yolk-shell nanosystem based on NIR-elevated drug release and GSH depletion-enhanced Fenton-like reaction for synergistic cancer therapy

In this study, a versatile doxorubicin (DOX)-loaded yolk-shell nano-particles (HMCMD) assembled with manganese dioxide (MnO₂) as the core and copper sulfide (HMCuS) as the mesoporous (∼ 6.4 nm) shell, was designed and synthesized. The resulting HMCMD possess excellent photothermal conversion efficiency. The DOX release from the yolk-shell nanoparticles could be promoted by laser irradiation, which increased the chemotherapy of DOX. Meanwhile, Mn²⁺ could be released from the HMCMD through a redox reaction between MnO₂ and abundant glutathione (GSH) in tumor cells. The released Mn²⁺ could promote the decomposition of the intracellular hydrogen peroxide (H₂O₂) by Fenton-like reaction to generate the highly toxic hydroxyl radicals (·OH), thus exhibiting the effective chemodynamic therapy (CDT). Additionally, the efficiency of Mn²⁺-mediated CDT could be effectively enhanced by NIR irradiation. Further modification of polyethylene glycol (PEG) would improve the water solubility of the HMCMD to promote the uptake by MCF-7 cells. Hence, the HMCMD with synergistic effects of chemotherapy and chemodynamic/photothermal therapy would provide an alternative strategy in antitumor research.

Ionic liquid induced highly dense assembly of porphyrin in MOF nanosheets for photodynamic therapy

A facile fabrication of porphyrin-integrated MOF nanosheets as efficient photosensitizers for photodynamic therapy (PDT) is presented.