Encapsulation biomolecule

A more promising approach to release encapsulated biomolecules is to disrupt or change the phase behavior of the w/o-ME solution. One such method is to employ temperature however, the change in temperature required to alter the phase behavior changes... 

The enzymes are stabilized due to hydrogen-bonding and electrostatic interactions with NH and SiOH groups. Furthermore, the gels retain a significant amount of water necessary for the stability of the encapsulated biomolecules. As a result, almost all of the enzyme (Kl, 94% K3, 98% K4, 100% K5, 100%) is stable and is released from the gels when placed... 

Release of DNA in vivo takes place due to the increased acidic conditions inside living cells that result in the destabilization of the ORMOSIL-DNA complex. SiCVbased nanoparticles, in fact, do not release encapsulated biomolecules because of the strong hydrogen bonding between the biomolecule s polar centres and the silanols at the cage surface (as ORMOSIL-entrapped hydrophobic molecules are not leached in aqueous systems due to strong hydrophobic interactions).17... 

Bioactive films made by the LbL technique have been extensively studied by many scientific groups worldwide. The films can host not only bioactive molecules introduced as constituents of the film, but also carriers with encapsulated biomolecules, for instance liposomes (Lip) and polymeric capsules (Fig. 2). Stimuli-sensitive... 

Mak WC, Bai J, Chang XY, et al. (2009) Matrix-assisted colloidosome reverse-phase layer-by-layer encapsulating biomolecules in hydrogel microcapsules with extremely high efficiency and retention stability. Langmuir 25 769-775... 

Phase separation Avoid solvents and high temperatures possibility to encapsulate biomolecules Lack of control over microarchitecture limited pore size 7,29... 

Biocompatible microgels for the delivery of protein and DNA biomolecules were developed using acrylamide monomer, a bisacrylamide acetal crosslinker and potassium persulphate initiator. Encapsulation was shown to provide protection from enzymatic degradation of the protein or DNA. These particles demonstrated pH sensitivity such that in an acidic environment, as in the lysosome, the polymeric carrier degraded and released the encapsulated biomolecule. 9 refs. 

The collective results from these studies help to establish several important conclusions 1) biological macromolecules, in general, are stable within sol-gel derived silica glasses, 2) the dopant biomolecules act as templates for the formation of self-specific pores around them, 3) due to the porous nature of the matrix, external substrates are able to interact with confined proteins, 4) optical transparency of these glasses allows interactions of photons with encapsulated biomolecules and permits optical monitoring of molecular events related to structure and reactivity, and 5) biorecognilion based on proteins and enzymes encapsulated in sol-gel glasses is feasible. 

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