Time-resolved CIDEP and ESR studies of heavy metal-organic radical complexes. The uranyl-phenanthroquinone radical ions

Nanocomposites comprising metal-organic frameworks (MOFs) embedded in a polymeric matrix are promising carriers for drug delivery applications. While understanding the chemical and physical transformations of MOFs during the release of confined drug molecules is challenging, this is central to devising better ways for controlled release of therapeutic agents. Herein we demonstrate the efficacy of synchrotron microspectroscopy to track the in situ release of 5-fluorouracil (5-FU) anticancer drug molecules from a drug@MOF/polymer composite (5-FU@HKUST-1/polyurethane). Using experimental time-resolved infrared spectra jointly with newly developed density functional theory calculations, we reveal the detailed dynamics of vibrational motions underpinning the dissociation of 5-FU bound to the framework of HKUST-1 upon water exposure. We discover that HKUST-1 creates hydrophilic channels within the hydrophobic polyurethane matrix hence helping to tune drug release rate. The synergy between a hydrophilic MOF with a hydrophobic polymer can be harnessed to engineer a tunable nanocomposite that alleviates the unwanted burst effect commonly encountered in drug delivery.<br>

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Elucidating the Structural Evolution of a Highy Porous Responsive Metal-Organic Framework (DUT-49(M)) upon Guests Desorption by Time-Resolved In-Situ Powder X-Ray Diffraction

10.26434/chemrxiv.12753593.v1 ◽

2020 ◽

Author(s):

Bikash Garai ◽

Volodymyr Bon ◽

Francesco Walenszus ◽

Azat Khadiev ◽

Dmitri Novikov ◽

...

Keyword(s):

Adsorption Isotherms ◽

Metal Organic Framework ◽

Structural Evolution ◽

Structural Transformations ◽

X Ray Diffraction ◽

Time Resolved ◽

X Ray ◽

Metal Organic ◽

Subcritical Fluid

Variation in the metal centres of M-M paddle-wheel SBU results in the formation of isostructural DUT-49(M) frameworks. However, the porosity of the framework was found to be different for each of the structures. While a high and moderate porosity was obtained for DUT-49(Cu) and DUT-49(Ni), respectively, other members of the series [DUT-49(M); M= Mn, Fe, Co, Zn, Cd] show very low porosity and shapes of the adsorption isotherms which is not expected for op phases of these MOFs. Investigation on those MOFs revealed that those frameworks undergo structural collapse during the solvent removal at the activation step. Thus, herein, we aimed to study the detailed structural transformations that are possibly occurring during the removal of the subcritical fluid from the framework.

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Elucidating the Drug Release from Metal-Organic Framework Nanocomposites via in Situ Synchrotron Microspectroscopy and Theoretical Modelling

10.26434/chemrxiv.9975389.v1 ◽

2019 ◽

Author(s):

Barbara Souza ◽

Lorenzo Dona ◽

Kirill Titov ◽

Paolo Bruzzese ◽

Zhixin Zeng ◽

...

Keyword(s):

Drug Delivery ◽

Drug Release ◽

Density Functional ◽

Metal Organic Framework ◽

Density Functional Theory Calculations ◽

Theoretical Modelling ◽

Time Resolved ◽

Drug Molecules ◽

Metal Organic

Nanocomposites comprising metal-organic frameworks (MOFs) embedded in a polymeric matrix are promising carriers for drug delivery applications. While understanding the chemical and physical transformations of MOFs during the release of confined drug molecules is challenging, this is central to devising better ways for controlled release of therapeutic agents. Herein we demonstrate the efficacy of synchrotron microspectroscopy to track the in situ release of 5-fluorouracil (5-FU) anticancer drug molecules from a drug@MOF/polymer composite (5-FU@HKUST-1/polyurethane). Using experimental time-resolved infrared spectra jointly with newly developed density functional theory calculations, we reveal the detailed dynamics of vibrational motions underpinning the dissociation of 5-FU bound to the framework of HKUST-1 upon water exposure. We discover that HKUST-1 creates hydrophilic channels within the hydrophobic polyurethane matrix hence helping to tune drug release rate. The synergy between a hydrophilic MOF with a hydrophobic polymer can be harnessed to engineer a tunable nanocomposite that alleviates the unwanted burst effect commonly encountered in drug delivery.<br>

Download Full-text