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Pimozide is a first-generation antipsychotic used in the treatment of schizophrenia, Gilles de la Tourette syndrome, and other chronic psychoses. Its in vivo efficacy is limited by poor solubility and consequent poor bioavailability. Therefore, adipic acid was used as a coformer for the preparation of a binary product with improved pharmaceutical properties. The thermal behavior of the liquid-assisted grinding products of compositions included in the range 0.1 < XPMZ < 0.9 has been interpreted using a thermo-dynamic model according to which the two components originate a new crystalline entity in molar ratio pimozide:adipic acid 0.66:0.33, which forms an eutectic system with adipic acid. The model was confirmed using the quantitative analysis of the melting peaks and using the X-ray diffraction measurements from powders and single crystals. In particular, the latter have demonstrated that the new entity resulting from the pimozide:adipic acid 0.66:0.33 composition is actually salt [PMZH]2[adipate]. The crystalline product was characterized, from a pharmaceutical perspective, in terms of solubility and wettability (contact angle). Then, a tablet formulation was developed, and its dissolution behavior was compared to a commercial product considered as a reference. The new entity showed improved pharmaceutical properties in terms of solubility and wettability compared to the pure drug in both deionized water and bio-relevant fluids simulating oral administration in fed and fasted conditions. The tablets containing the new crystalline form can make this virtually insoluble drug available for absorption within minutes regardless of the variability in gastric conditions. [ABSTRACT FROM AUTHOR]

Noble gas xenon (Xe) is an excellent anesthetic gas, but its rarity, high cost and constrained production prohibits wide use in medicine. Here, we have developed a closed‐circuit anesthetic Xe recovery and reusage process with highly effective CO2‐specific adsorbent CUPMOF‐5 that is promising to solve the anesthetic Xe supply problem. CUPMOF‐5 possesses spacious cage cavities interconnected in four directions by confinement throat apertures of ~3.4 Å, which makes it an ideal molecular sieving of CO2 from Xe, O2, N2 with the benchmark selectivity and high uptake capacity of CO2. In situ single‐crystal X‐ray diffraction (SCXRD) and computational simulation solidly revealed the vital sieving role of the confined throat and the sorbent‐sorbate induced‐fit strengthening binding interaction to CO2. CUPMOF‐5 can remove 5 % CO2 even from actual moist exhaled anesthetic gases, and achieves the highest Xe recovery rate (99.8 %) so far, as verified by breakthrough experiments. This endows CUPMOF‐5 great potential for the on‐line CO2 removal and Xe recovery from anesthetic closed‐circuits. [ABSTRACT FROM AUTHOR]

Stimuli‐responsive physisorbents that undergo reversible structural transformations induced by external stimuli (e.g. light, guests, or heat) offer the promise of utility in gas storage and separation. Whereas reports on guest or light‐responsive sorbents have increased in recent years, we are unaware of reports on sorbents that exhibit both light and guest‐induced structural transformations. Herein, we report that the square lattice, sql, topology coordination network Zn(fba)(bis) ⋅ 2DMF (sql‐5,6‐Zn‐α, 5=trans‐4,4′‐bis(1‐imidazolyl)stilbene=bis, 6=2,2‐bis(4‐carboxyphenyl)hexafluoropropane=H2fba) underwent single‐crystal‐to‐single‐crystal transformation (SCSC) upon activation, affording nonporous sql‐5,6‐Zn‐β. Parallel alignment at 3.23 Å of olefinic moieties on adjacent bis ligands in sql‐5,6‐Zn‐α enabled SCSC [2+2] photocycloaddition upon exposure to UV light (365 nm) or sunlight. sql‐5,6‐Zn‐α thereby transformed to mot‐5,6‐Zn‐α, which was subsequently activated to the narrow pore phase mot‐5,6‐Zn‐β. sql‐5,6‐Zn‐β and mot‐5,6‐Zn‐β both exhibited S‐shaped adsorption isotherms characteristic of guest‐induced structural changes when exposed to CO2 at 195 K (type‐F–IV and type F–I, respectively). Cycling experiments conducted upon sql‐5,6‐Zn‐β reduced particle size after cycle 1 and induced transformation into a rare example of a shape memory coordination network, sql‐5,6‐Zn‐γ. Insight into this smorgasbord of SCSC phase changes was gained from in situ PXRD, single crystal XRD and 1H NMR spectroscopy experiments. [ABSTRACT FROM AUTHOR]

Antibiotic resistance is a significant global concern, necessitating the development of either new antibiotics or advanced delivery methods. With this in mind, we report on the synthesis and characterisation of a new family of Metal–Organic Frameworks (MOFs), OnG6 MOFs, designed to act as multi-drug carriers for bacterial infection treatment. OnG6 is based on the pro-drug 4,4′-azodisalicylic acid (AZDH4), which in vivo produces two equivalents of para-aminosalicylic acid (ASA), a crucial drug for M. tuberculosis treatment. X-ray and computational studies revealed that OnG6 MOFs are mesoporous MOFs with etb topology and an [M2(AZD)] formula (M = Zn, OnG6-Zn; Mg, OnG6-Mg; Cu, OnG6-Cu; and Co, OnG6-Co), featuring 1-dimensional channel type pores of 25 Å diameter. OnG6 MOFs are the first reported MOFs bearing the ligand AZDH4, joining the family of mesoporous MOFs arranged in a honeycomb pattern. They absorb isoniazid (INH) and ciprofloxacin (CIPRO) with the former being a specific antibiotic for M. tuberculosis, and the latter being a broader-spectrum antibiotic. The stability of the MOFs and their capacity for antibiotic uptake depend on the nature of the metal ion, with OnG6-Mg demonstrating the highest drug absorption. The antimicrobial activity of these species was assessed against S. aureus and E. coli, revealing that the carriers containing CIPRO displayed optimal efficacy. [ABSTRACT FROM AUTHOR]