Transformation of naphthopyran into a colored merocyanine species in polymeric materials is achieved using mechanical force. We demonstrate that the mechanochemical reactivity of naphthopyran is critically dependent on the regiochemistry, with only one particular substitution pattern leading to successful mechanochemical activation. Two alternative regioisomers with different polymer attachment points are demonstrated to be mechanochemically inactive. This trend in reactivity is accurately predicted by DFT calculations, reinforcing predictive capabilities in mechanochemical systems. We rationalize the reactivity differences between naphthopyran regioisomers in terms of the alignment of the target C-O pyran bond with the direction of the applied mechanical force and its effect on mechanochemical transduction along the reaction coordinate.
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http://dx.doi.org/10.1021/jacs.6b07610 | DOI Listing |
Front Biosci (Landmark Ed)
January 2025
Department of Oral and Maxillofacial Surgery, The First Affiliated Hospital of Fujian Medical University, Fujian Provincial Key Laboratory of Stomatology, National Regional Medical Center, Binhai Campus of The First Affiliated Hospital, 350005 Fuzhou, Fujian, China.
Background: In this study, we prepared a porous gradient scaffold with hydroxyapatite microtubules (HAMT) and chitosan (CHS) and investigated osteogenesis induced by these scaffolds.
Methods: The arrangement of wax balls in the mold can control the size and distribution of the pores of the scaffold, and form an interconnected gradient pore structure. The scaffolds were systematically evaluated and for biocompatibility, biological activity, and regulatory mechanisms.
Pharmaceutics
January 2025
Department of Medicinal Plants, Faculty of Agriculture and Natural Resources, Arak University, Arak 38156-8-8349, Iran.
In the 21st century, thanks to advances in biotechnology and developing pharmaceutical technology, significant progress is being made in effective drug design. Drug targeting aims to ensure that the drug acts only in the pathological area; it is defined as the ability to accumulate selectively and quantitatively in the target tissue or organ, regardless of the chemical structure of the active drug substance and the method of administration. With drug targeting, conventional, biotechnological and gene-derived drugs target the body's organs, tissues, and cells that can be selectively transported to specific regions.
View Article and Find Full Text PDFPharmaceutics
January 2025
University of Belgrade, Faculty of Technology and Metallurgy, Karnegijeva 4, 11000 Belgrade, Serbia.
To develop and evaluate graphene oxide/gelatin/alginate scaffolds for advanced wound therapy capable of mimicking the native extracellular matrix (ECM) and bio-stimulating all specific phases of the wound healing process, from inflammation and proliferation to the remodeling of damaged skin tissue in three dimensions. The scaffolds were engineered as interpenetrating polymeric networks by the crosslinking reaction of gelatin in the presence of alginate and characterized by structural, morphological, mechanical, swelling properties, porosity, adhesion to the skin tissue, wettability, and in vitro simultaneous release of the active agents. Biocompatibility of the scaffolds were evaluated in vitro by MTT test on fibroblasts (MRC5 cells) and in vivo using assay.
View Article and Find Full Text PDFPharmaceutics
January 2025
Laboratory on Structure and Properties of Polymers, Faculty of Chemistry and Pharmacy, University of Sofia, 1, J. Bourchier Blvd., 1164 Sofia, Bulgaria.
: This study is an attempt to reveal the potential of two types of interpenetrating polymer network (IPN) hydrogels based on poly(2-hydroxyethyl methacrylate) (PHEMA) and poly(N,N-dimethylacrylamide) (PDMAM). These IPNs were evaluated for their potential for dermal delivery of the hydrophobic drug dexamethasone (DEX). : The two types of IPNs were analyzed for their rheological behavior, swelling characteristics, and drug-loading capacity with DEX.
View Article and Find Full Text PDFPharmaceutics
January 2025
Department of Materials Science, Graduate School of Pure and Applied Sciences, University of Tsukuba, Tennoudai 1-1-1, Tsukuba 305-8573, Ibaraki, Japan.
Orally administered sorafenib has shown limited improvement in overall survival for non-small-cell lung cancer patients, likely due to poor pharmacokinetics and adverse effects, including gastrointestinal toxicity. To address these issues, we developed silica-containing antioxidant nanoparticles (siRNP) as a carrier to enhance the therapeutic efficacy of lipophilic sorafenib. Sorafenib was loaded into siRNP via dialysis (sora@siRNP).
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