resumo
The photoactivatable CO-releasing molecule (photoCORM) [Mo(CO)(3)(CNCH2COOH)(3)] (ALF795) has been incorporated into a Zn,Al layered double hydroxide (LDH) host by a coprecipitation synthesis strategy. Powder X-ray diffraction (PXRD) of the resultant material Zn,Al-ALF795 showed that the ALF795 guest molecules assembled into a monolayer to give a basal spacing of 16.0 angstrom. FTIR and(13)C{H-1} CP MAS NMR spectroscopy confirmed that the molecular structure of the tricarbonyl complex was retained upon intercalation. Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS) and elemental analyses confirmed the phase-purity of Zn,Al-ALF795. The myoglobin assay was used to demonstrate that intercalated ALF795 retains the photoactive behavior of the free CORM, with a substantial fraction (42 %) of the high CO payload (2.46 mmol g(-1)) being released after exposure to UV light for 3 h under simulated physiological conditions. In addition, gas chromatography was used to track sequential light- and H2O2-triggered decarbonylation of free and intercalated ALF795. In biological buffer solution (HEPES), less than 2 % Mo leaching from Zn,Al-ALF795 took place after 5 h, showing the strong capacity of the LDH host to retain the unaltered complex and decarbonylation fragments.
palavras-chave
CARBON-MONOXIDE; NANOPARTICLES; DELIVERY; COMPLEX; OXIDE; EXCHANGE; CARRIERS; DESIGN
categoria
Chemistry
autores
Calhau, IB; Gomes, AC; Bruno, SM; Coelho, AC; Magalhaes, CIR; Romao, CC; Valente, AA; Goncalves, IS; Pillinger, M
nossos autores
agradecimentos
We acknowledge funding provided within the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020 & UIDP/50011/2020, and the CENTRO 2020 Regional Operational Programme (project references CENTRO-01-0145-FEDER-028031 and PTDC/QUI-QOR/28031/2017), financed by national funds through the FCT (Fundacao para a Ciencia e a Tecnologia)/MEC (Ministerio da Educacao e Ciencia) and when appropriate co-financed by the European Union through the European Regional Development Fund under the Portugal 2020 Partnership Agreement. The position held by S. M. B. was funded by national funds (OE), through FCT, I.P., in the scope of the framework contract foreseen in the numbers 4, 5 and 6 of article 23 of the Decree-Law 57/2016 of 29 August, changed by Law 57/2017 of 19 July.