Nano apatite growth on demineralized bone matrix capped with curcumin and silver nanoparticles: Dental implant mechanical stability and optimal cell growth analysis.

OBJECTIVES: The prevention of implant-associated infections is becoming increasingly clinically important in the field of dentistry. Extensive investigations into the development of innovative antibacterial materials that interact effectively to reinforce their functionality are currently being conducted in the biomedical sector. In the present study, a novel dental nano putty (D-nP) has been developed using demineralized bone matrix (DBM), calcium sulfate hemihydrate (CSH), curcumin nanoparticles (CU-NPs), and silver nanoparticles (AgNPs). METHODS: The produced D-nP was evaluated using physicochemical, mechanical, and in vitro analyses. Surface characterization, particularly the analysis of calcium and phosphorus content, was performed before and after immersion in the simulated body fluid (SBF). In addition, the impact of surface treatment on biological activity was studied. RESULTS: The results showed that the mechanical properties of the D-nP were outstanding and its performance is promising. D-nP exhibited excellent antibacterial activity against Actinomyces naeslundii (5.22 ± 0.07 mm) and Streptococcus oralis (5.41 ± 0.1 mm). The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay was conducted using MG-63 osteoblast cells, which exhibited 95 % viability in D-nP. CONCLUSIONS: Based on these characterization results, the D-nP developed in this study exhibited excellent performance for tooth tissue in bone repair.

N-Alkylation and N-Methylation of Amines with Alcohols Catalyzed by Nitrile-Substituted NHC-Ir(III) and NHC-Ru(II) Complexes.

A series of nitrile-modified N-heterocyclic carbene (NHC) complexes of Ir(III) (2a-e) and Ru(II) (3a-d) have been prepared by transmetallation of [IrCp*Cl2]2 and [RuCl2(p-cymene)]2 forming an in situ NHC-Ag complex. The structures of all complexes were characterized by 1H NMR, 13C NMR, and Fourier transform infrared (FT-IR) spectroscopies. And the structures were clearly elucidated by performing X-ray diffraction studies on 2b, 3a, and 3c single crystals. The complexes of NHC-Ir(III) (2a-e) and NHC-Ru(II) (3a-d) were investigated in the N-alkylation reaction of aniline derivatives with benzyl alcohols to form N-benzyl amines and in the N-methylation reaction of aniline derivatives with methanol. Both reactions were performed in solvent-free media. The Ir(III) complexes (2a-e) were found to perform essentially better than similar Ru(II) complexes (3a-d) in the N-alkylation and N-methylation reactions. Among the Ir(III) complexes (2a-e), the best results were obtained with 2b. The catalytic mechanisms of both reactions were revealed by 1H NMR study. Formation of Ir-hydride species was observed for both reactions. This new report provides useful information to evaluate the activity of complexes and the differences in sensitivity between the NHCs.

Curcumin nanoparticles supported gelatin-collagen scaffold: Preparation, characterization, and in vitro study.

It is possible to reveal the potential of water-insoluble drugs by increasing their solubility in water with some nanotechnology techniques. Nanosuspension technology can solve this problem by increasing the water solubility and as well as bioavailability of these drugs. The present work is pointed at the evaluation of nanosuspension of curcumin, a poorly water-soluble drug. The Curcumin nanoparticules (CNs) were prepared with ultrasonnication method using dichloromethane as solvent and water as antisolvent and characterized via spectroscopic methods (UV-vis and FT-IR) and Scanning Electron Microscopy (SEM). Curcumin nanoparticules Biofilms (CNs-BF) supported gelatin-collagen scaffold were prepared. Curcumin nanoparticles were obtained by nanosuspension technique. And then, to overcome the limited effects of curcumin such as solubility and bioavailability, nanoparticle films were prepared by incorporating it into the structure of biocompatible collagen-gelatin scaffolds. Curcumin is limited by some factors that limit its clinical applicability, such as low oral bioavailability, poor water solubility and rapid degradation. However, they can be applied clinically when they are included in the structure of biocompatible gelatin-collagen scaffolds.

C(acyl)-C(sp2) and C(sp2)-C(sp2) Suzuki-Miyaura cross-coupling reactions using nitrile-functionalized NHC palladium complexes.

Application of N-heterocyclic carbene (NHC) palladium complexes has been successful for the modulation of C-C coupling reactions. For this purpose, a series of azolium salts (1a-f) including benzothiazolium, benzimidazolium, and imidazolium, bearing a CN-substituted benzyl moiety, and their (NHC)2PdBr2 (2a-c) and PEPPSI-type palladium (3b-f) complexes have been systematically prepared to catalyse acylative Suzuki-Miyaura coupling reaction of acyl chlorides with arylboronic acids to form benzophenone derivatives in the presence of potassium carbonate as a base and to catalyse the traditional Suzuki-Miyaura coupling reaction of bromobenzene with arylboronic acids to form biaryls. All the synthesized compounds were fully characterized by Fourier Transform Infrared (FTIR), and 1H and 13C NMR spectroscopies. X-ray diffraction studies on single crystals of 3c, 3e and 3f prove the square planar geometry. Scanning Electron Microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), metal mapping analyses and thermal gravimetric analysis (TGA) were performed to get further insights into the mechanism of the Suzuki-Miyaura cross coupling reactions. Mechanistic studies have revealed that the stability and coordination of the complexes by the CN group are achieved by the removal of pyridine from the complex in catalytic cycles. The presence of the CN group in the (NHC)Pd complexes significantly increased the catalytic activities for both reactions.