Coordination Modulation Method To Prepare New Metal–Organic Framework-Based CO-Releasing Materials Carmona Fernández, Francisco Jesús Rodríguez Maldonado, Carmen Ikemura, Shuya Romão, Carlos C. Huang, Zhehao Xu, Hongyi Zou, Xiaodong Kitagawa, Susumu Furukawa, Shuhei Barea Martínez, Elisa María carbon monoxide metal−organic framework solid-state materials guest inclusion Version aceptada / Accepted version Aluminum-based metal–organic frameworks (MOFs), [Al(OH)(SDC)]n, (H2SDC: 4,4′-stilbenedicarboxylic acid), also known as CYCU-3, were prepared by means of the coordination modulation method to produce materials with different crystal size and morphology. In particular, we screened several reagent concentrations (20–60 mM) and modulator/ligand ratios (0–50), leading to 20 CYCU x_y materials (x: reagent concentration, y = modulator/ligand ratio) with different particle size and morphology. Noteworthy, the use of high modulator/ligand ratio gives rise to a new phase of CYCU-3 (CYCU-3′ x_50 series), which was structurally analyzed. Afterward, to test the potential of these materials as CO-prodrug carriers, we selected three of them to adsorb the photo- and bioactive CO-releasing molecule (CORM) ALF794 [Mo(CNCMe2CO2H)3(CO)3] (CNCMe2CO2H = 2-isocyano-2-methyl propionic acid): (i) CYCU-3 20_0, particles in the nanometric range; (ii) CYCU-3 50_5, bar-type particles with heterogeneous size, and (iii) CYCU-3′ 50_50, a new phase analogous to pristine CYCU-3. The corresponding hybrid materials were fully characterized, revealing that CYCU-3 20_0 with the smallest particle size was not stable under the drug loading conditions. Regarding the other two materials, similar ALF794 loadings were found (0.20 and 0.19 CORM/MOF molar ratios for ALF794@CYCU-3 50_5 and ALF794@CYCU-3′ 50_50, respectively). In addition, these hybrid systems behave as CO-releasing materials (CORMAs), retaining the photoactive properties of the pristine CORM in both phosphate saline solution and solid state. Finally, the metal leaching studies in solution confirmed that ALF794@CYCU-3′ 50_50 shows a good retention capacity toward the potentially toxic molybdenum fragments (75% of retention after 72 h), which is the lowest value reported for a MOF-based CORMA to date. 2024-02-04T16:27:04Z 2024-02-04T16:27:04Z 2018-08-28 journal article ACS Appl. Mater. Interfaces 2018, 10, 37, 31158–31167 https://hdl.handle.net/10481/88138 https://doi.org/10.1021/acsami.8b11758 eng http://creativecommons.org/licenses/by-nc-nd/4.0/ open access Attribution-NonCommercial-NoDerivatives 4.0 Internacional ACS