This review is devoted to the most recent developments (2000–2005) of sol–gel materials at interface with biology. In context bioencapsulation in mineral hosts, novel synthetic approaches have been designed, allowing immobilization numerous proteins, enzymes and immune molecules as well poly-saccharides, phospholipids nucleic acids. These efforts led development new biosensors bioreactors. A similar trend was also observed for whole cell encapsulation, survival periods over several weeks now...

A wide variety of biomolecules, ranging over proteins, enzymes, antibodies and even whole cells, have been embedded within sol-gel glasses. They retain their bioactivity remain accessible to external reagents by diffusion through the porous silica. Sol-gel glasses can be cast into desired shapes are optically transparent, so it is possible couple optics make photonic devices biosensors. The high specificity sensitivity enzymes allows detection traces chemicals. Entrapped living cells used...

The influence of poly(lysine) and poly(arginine) on silicate solutions silica sols has been investigated. In both cases, solid formation could be observed that appeared to depend the polymer chain length. Polyelectrolytes induced gelation diluted sodium solutions. Studies silicic acid content using colorimetric molybdosilicate method suggested polymers act as gelating agents oligomers via electrostatic interactions favor condensation. case sols, quasi-elastic light scattering measurements...

Common Anabaena, Calothrix, and Leptolyngbya cyanobacteria are shown to form Au, Ag, Pd, Pt nanoparticles of well-controlled size. These synthesized intra-cellularly, naturally released in the culture medium, where they stabilized by algal polysaccharides, allowing their easy recovery. The size recovered particles as well reaction yield is depend on genus. Investigations nanoparticle formation indicate that intracellular nitrogenase enzyme responsible for metal reduction but cellular...

Silica-collagen type I nanocomposite hydrogels are evaluated as medicated dressings to prevent infection in chronic wounds. Two antibiotics, gentamicin and rifamycin, encapsulated a single step within plain silica nanoparticles. Their antimicrobial efficiency against Pseudomonas aeruginosa Staphylococcus aureus is assessed. Gentamycin-loaded 500 nm particles can be immobilized at high dose concentrated collagen without modifying their fibrillar structure or impacting on rheological behavior...

Identification of silica sol-gel chemistry with silicon alkoxide hydrolysis and condensation processes is common in modern materials science. However, aqueous silicates exhibit several features indicating that they may be more suitable precursors for specific fields research applications related to biology medicine. In this Account, we illustrate the potentialities such biomimetic studies, bio-hybrid material design, bioencapsulation routes. We emphasize natural relevance, biocompatibility,...

The dynamic behavior of nanoscale mesoporous oxide materials exposed to aqueous solutions under biologically relevant conditions is shown be highly dependent on composition, porosity, and calcination temperature. Dynamic processes were followed as a function exposure thin films amenable environmental ellipsometry porosimetry for the analysis mechanical strength pore size distributions exposure. Additionally, X-ray photoelectron spectroscopy was used elucidation compositional changes...

Over the last decade, ecodesign has been introduced as a concept and methodological framework to identify improve sustainability in product development. In this context, 12 principles of green chemistry provide suitable guidelines for elaboration molecules materials conditions that meet some ecodesign-related criteria. Sol–gel is an interesting domain be examined perspective because it was early identified eco-friendly process compared traditional routes ceramics glasses. Thus not surprising...

Associating collagen with biodegradable hydrophobic polyesters constitutes a promising method for the design of medicated biomaterials. Current collagen-polyester composite hydrogels consisting pre-formed polymeric particles encapsulated within low concentrated hydrogel suffer from poor physical properties and drug loading. Herein, an amphiphilic platform associating dense up to 50 wt% different hydrophobicity chain length is developed. An original fabrication disclosed based on in situ...

E. coli bacteria were encapsulated within silica gels and aged at room temperature in the absence of nutrients. Their viability was studied as a function time using different tests. The plate count technique gives number culturable that remain able to form colonies presence culture medium. metabolic activity toward glycolysis followed by 14C titration 13C NMR spectroscopy. Several sol–gel matrices tested order improve trapped bacteria. best results obtained when encapsulation is performed...

The viability of bacteria in the presence sol–gel reagents has been studied order to define best experimental conditions for encapsulation E. coli. β-galactosidase activity these bacteria, trapped silica matrices, was then analyzed. Two routes, using alkoxide and aqueous precursors, have used compared. It appears that route is less damaging than one. Moreover matrix slow down lysis cell membranes when are aged without nutrient.

The possibility to understand natural strategies build‒up silica SiO 2 networks relies on the investigations of kinetics precursors polymerization in presence biopolymers. silicomolybdic acid spectrophotometric method allows study this process at molecular level, provided that reliable procedures are available. Moreover, special care must be taken avoid interfering processes induced by inorganic and/or bio‐organic species found solution. In order illustrate possibilities and limitations...

Biopolymers have already been widely used to control the growth of inorganic particles. However, some these natural macromolecules present an intrinsic chemical and structural variability that may influence their templating efficiency. We therefore compared ability three different sources alginate formation Co, Ni, CoNi nanoparticles. Variations in particle size, structure, magnetic properties were observed depending on composition. The more stable gels allowed CoxNi100-x nanoalloys over...

Biomineralization processes are now fully recognized as inspiring systems for the design of new materials. In case silica, formation diatom shell or sponge spicule has attracted much attention in last decade since it could provide key information to elaborate hierarchically structured materials and nanodevices. these two examples, mineral phase is thought be formed by controlled assembly nanoparticles generated vivo from diluted precursor solutions, presence biomolecular templates. The...

We present a simple one-pot crystallization method, inspired by biological conditions, for the synthesis of hydroxyapatite (Ca5(PO4)3OH) nanocrystals. The reaction proceeds via NH3 vapor diffusion into CaCl2−NaH2PO4 mixed solution that is free any organic additives. advantage relying on acidic calcium-phosphate precursors here is, first, can be performed at room temperature within short time and without direct pH control and, second, it does not produce secondary phases or byproduct....

Hybrid nanoparticles have great potential for biotechnological and biomedical applications. It was recently proposed that biopolymer/silica nanomaterials could be easily obtained by adapting traditional routes used in pharmaceutical science to design polymer nanoparticles. In this paper, we demonstrate core–shell gelatine/silica can using a nano-emulsion route, taking advantage of the thermal gelation properties biopolymer its strong "biomimetic" affinity silicates. The formation silica...

Klebsormidium flaccidum algal cells exhibiting the ability to form gold nanoparticles intra-cellularly in suspension were encapsulated within silica gels. Optical and electronic microscopy indicate that entrapped maintain their reduce salts. A difference kinetics of colloid formation absence or presence could be followed by UV-visible absorption spectroscopy, confirming bio-mediated nature reduction process. Study photosynthetic activity algae showed encapsulation process protects from...