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Bioszkła i organiczno-nieorganiczne kompozyty dla inżynierii tkankowej kości

John Ł.

Wiadomości Chemiczne

2012

[Z] 66, 1-2

21-39

The most demanded biomaterials for bone tissue engineering could be classified in two main sol-gel derived groups: bioglasses and organic-inorganic composites. The first of these include bioactive ceramics such as calcium phosphates (Tab. 2) [1], glasses and glass ceramics [2], and so-called inert ceramics (Tab. 1) such as Al2O3, zirconium and titanium dioxide, and carbon-based materials [3, 4]. Second-group of compounds constitute bioactive organic-inorganic hybrids, generally based on organic matrix and various inorganic dopants. Biomaterials in contact with human plasma and bone stem cells form, on their surface, hydroxyapatite Ca10(PO4)6(OH)2 (HAp) and its derivatives (Tab. 2). HAp-layer initiates bone growth and reconstruction of treated fragment (Fig. 2). These materials, due to the high degree of biocompability are considered as the most valuable compounds for bone surgery [5]. Extremely rapid development of biomaterials used in medicine caused the production of implants with different properties (Scheme 1). The real revolution and technological progress have brought biomimetic composites that mimic naturally occurring solutions in living organisms. The role of such implants is not only replacing the damaged parts of body, but – due to the appropriate morphology and composition – stimulating the growth of living cells (Fig. 3) and final bone regeneration. This article is devoted to this type of biomaterials proposed for bone tissue engineering.

Sol-gel derived Li-ion conducting polymer electrolytes

Żelazowska E., Rysiakiewicz-Pasek E., Borczuch-Łączka M.

Materials Science Poland

2005

Vol. 23, No. 1

177--194

Organic-inorganic hybrids have recently become a remarkable family of amorphous polymer materials with promising potential applications. In the present study, sol-gel derived organic-inorganic hybrid electrolytes doped with lithium salts (LiCl, LiClO4) were produced from inorganic and organic precursors such as tetraethyl orthosilicate, poly(ethylene oxide), poly(ethylene glycol), propylene oxide, propylene carbonate, ethylene glycol, and 1,2-propylene glycol. The hybrid electrolytes were obtained in the form of flexible or glassy materials depending on the composition and heat treatment temperature (ranging from 80 to 125 ?C). The morphology, structure and elemental chemical composition of the electrolytes obtained were examined by scanning electron microscopy equipped with energy dispersive X-ray spectroscopy (SEM/EDS), FTIR spectroscopy, and X-ray diffraction (XRD). Infrared spectroscopy and SEM observation results indicate that the structural properties of the synthesized materials are significantly influenced by organic additives and the sol-gel preparation procedure. The formation of organic group-O-Si linkages was confirmed by infrared spectra in all of the electrolytes obtained. The results of FTIR analysis are in a good agreement with 13C and 1H MAS NMR spectroscopy measurements performed for the hydrolysed sols immediately before the gel transformation process and at early gel stages. These results have revealed an enhanced duration of the cross-linking process in the species prepared with low molecular mass glycols. Cells in an electrochromic window arrangement were prepared in order to observe the photometric and cyclic voltammetry characteristics of thin-film electrochromic systems with the investigated hybrid materials employed as electrolytes. The results indicate that the inorganic-organic hybrids synthesized in this work are promising electrolytes for thin film electrochromic systems based on WO3.