Metal–Organic Frameworks as Drug Delivery Platforms for Ocular Therapeutics

Abstract

Metal-organic frameworks (MOFs) have been evaluated as potential nanocarriers for intra-ocular incorporation of brimonidine tartrate to treat chronic glaucoma. Experimental results show that UiO-67 and MIL-100 (Fe) exhibit the highest loading capacity with values up to 50-60 wt.%, while the performance is quite limited for MOFs with narrow cavities (below 0.8 nm, e.g. UiO-66 and HKUST-1). The large loading capacity in UiO-67 is accompanied by an irreversible structural amorphization in aqueous and physiological media that promotes extended release kinetics above 12 days. Compared to the traditional drawbacks associated with the sudden release of the commercial drugs (e.g., ALPHAGAN), these results anticipate UiO-67 as a potential nanocarrier for drug delivery in intra-ocular therapeutics. These promising results are further supported by cytotoxicity tests using retinal photoreceptor cells (661W). Toxicity of these structures (including the metal nodes and organic ligands) for retinal cells is rather low for all samples evaluated, except for HKUST-1.

Rapid Electrochemical Quantification for In Vitro Release Trait of Ophthalmic Drug Loaded within Mucoadhesive Metal Organic Framework (MOF)

“…The signature peak around 537 cm −1 is related to the Fe−O vibration of Fe−O−C coordination linkage and was the most important peak which confirmed the presence of MOF. Additionally, it was found that the linkages due to ligand amino terephthalic acid are shifted in the synthesized FeMOF which further confirms the formation of MOF through the attachment of the ligand to the metal surface [20,21] …”

“…Additionally, it was found that the linkages due to ligand amino terephthalic acid are shifted in the synthesized FeMOF which further confirms the formation of MOF through the attachment of the ligand to the metal surface. [20,21] TGA analysis performed on Fe-MOF ( Figure 2A) reveals a two-step weight loss process. For the intact NH 2 -MIL-88(Fe) an initial weight loss occurred at ∼ 80°C, ascribed to removal/ evaporation of the ethanol used as a washing solvent and loss of water trapped within the cavities and water bonded to iron atoms.…”

Synergistic Chemotherapy and Photodynamic Therapy of Endophthalmitis Mediated by Zeolitic Imidazolate Framework‐Based Drug Delivery Systems

“…As a photosensitizer, MB was loaded into the ZIF‐8 and ZIF‐8‐PAA MOFs for PDT of endophthalmitis. Two kinds of commonly used methods, drug loading during MOFs synthesis and after MOFs synthesis, were compared through measuring the loading efficiency and loading capacity . After sufficient contacting and MB loading, MOFs were obtained by centrifugal precipitation.…”

Metal–Organic Framework Nanocarriers for Drug Delivery in Biomedical Applications

“…[77]. Copyright 2009, American Chemical Society drugs, antimicrobial agents, metabolic labeling molecules, antiglaucoma medication, and hormone [42,54,[81][82][83][84]. So far, targeted delivery has been achieved by three strategies, including passive delivery owing to enhanced permeability and retention (EPR) phenomenon, active/ ligand delivery (e.g., folic acid, antibody, and hyaluronic acid), and triggered delivery (e.g., pH, photoirradiation, temperature, and pressure).…”