The aim of this critical review is to provide a broad but digestible overview of mechanochemical synthesis, i.e. reactions conducted by grinding solid reactants together with no or minimal solvent. Although mechanochemistry has historically been a sideline approach to synthesis it may soon move into the mainstream because it is increasingly apparent that it can be practical, and even advantageous, and because of the opportunities it provides for developing more sustainable methods. Concentrating on recent advances, this article covers industrial aspects, inorganic materials, organic synthesis, cocrystallisation, pharmaceutical aspects, metal complexes (including metal–organic frameworks), supramolecular aspects and characterization methods. The historical development, mechanistic aspects, limitations and opportunities are also discussed (314 references).

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Mechanochemistry: opportunities for new and cleaner synthesis

https://digital.csic.es/bitstream/10261/63157/4/Gomez-Guillen-collagenreview_CSIC.pdf

Functional and bioactive properties of collagen and gelatin from alternative sources: A review

Current strategies of regenerative medicine are focused on the restoration of pathologically altered tissue architectures by transplantation of cells in combination with supportive scaffolds and biomolecules. In recent years, considerable interest has been given to biologically active scaffolds which are based on similar analogs of the extracellular matrix that have induced synthesis of tissues and organs. To restore function or regenerate tissue, a scaffold is necessary that will act as a temporary matrix for cell proliferation and extracellular matrix deposition, with subsequent ingrowth until the tissues are totally restored or regenerated. Scaffolds have been used for tissue engineering such as bone, cartilage, ligament, skin, vascular tissues, neural tissues, and skeletal muscle and as vehicle for the controlled delivery of drugs, proteins, and DNA. Various technologies come together to construct porous scaffolds to regenerate the tissues/organs and also for controlled and targeted release of bioactive agents in tissue engineering applications. In this paper, an overview of the different types of scaffolds with their material properties is discussed. The fabrication technologies for tissue engineering scaffolds, including the basic and conventional techniques to the more recent ones, are tabulated.

/pdf/polymeric-scaffolds-in-tissue-engineering-application-a-2sbenjc1po.pdf

Polymeric scaffolds in tissue engineering application: a review

Ionic substitutions in calcium phosphates synthesized at low temperature.

Indirect Solid Free Form Fabrication of Local and Global Porous, Biomimetic and Composite 3D Polymer-Ceramic Scaffolds

Mechanical and thermal properties of gelatin films at different degrees of glutaraldehyde crosslinking.

Stabilization of gelatin films by crosslinking with genipin.

Relationship between triple-helix content and mechanical properties of gelatin films.

In vitro bioactivity of gelatin sponges and hydroxyapatite-enriched gelatin sponges was tested through evaluation of the variations in their composition and morphology after soaking in simulated body fluid (1.5) for periods up to 21 days at 37°C. The presence of hydroxyapatite inside the sponges promotes the deposition of bonelike apatite crystals. The deposits are laid down as spherical aggregates, with mean diameters increasing from about 1–2 μm, after 4 days of soaking in simulated body fluid solution, up to about 3.5 μm in the samples soaked for 21 days. Simultaneously, the relative amount of inorganic phase increases up to about 56% wt, leading to a composite material with a composition quite close to that of bone tissue. The inorganic phase is a poor crystalline carbonated apatite similar to trabecular bone apatite. © 2001 Wiley Periodicals, Inc. J Biomed Mater Res 59: 709–714, 2002

Bonelike apatite growth on hydroxyapatite–gelatin sponges from simulated body fluid

Mechanical mixing of solid dicarboxylic acids of variable chain length HOOC(CH 2 ) n COOH (n = 1-7) with solid 1,4-diazabicyclo[2.2.2]octane generates the corresponding salts or co-crystals of the formula [N(CH 2 CH 2 ) 3 N]-H-[OOC(CH 2 ) n COOH] (n=1-7). Preparation of the same systems from solution has been instrumental for a full characterization of the mechanochemical products by means of single-crystal and powder-diffraction X-ray analyses, as well as by solid-state NMR. The acid-base adducts, whether involving proton transfer from the COOH group to the N-acceptor, that is having ( - ) O...H-N ( + ) interactions, or the formation of neutral O-H...N hydrogen bonds, show a melting point alternation phenomenon analogous to that shown by the neutral carboxylic acids. The carbon chemical shift tensors of the COOH group obtained from the sideband intensity of low speed spinning NMR spectra provide a reliable criterion for assigning the protonation state of the adducts.

Mechanochemical preparation of hydrogen-bonded adducts between the diamine 1,4-diazabicyclo[2.2.2]octane and dicarboxylic acids of variable chain length: An X-ray diffraction and solid-state NMR study

Katia Rubini

Papers

Mechanical and thermal properties of gelatin films at different degrees of glutaraldehyde crosslinking.

Stabilization of gelatin films by crosslinking with genipin.

Relationship between triple-helix content and mechanical properties of gelatin films.

Bonelike apatite growth on hydroxyapatite–gelatin sponges from simulated body fluid

Mechanochemical preparation of hydrogen-bonded adducts between the diamine 1,4-diazabicyclo[2.2.2]octane and dicarboxylic acids of variable chain length: An X-ray diffraction and solid-state NMR study