Search results for "high energy irradiation"
showing 4 items of 4 documents
On the mechanism of radiation synthesis of nanogels
2016
Radiation-engineered poly(N-vinyl pyrrolidone) nanogels are very interesting biocompatible nanocarriers for i.v. administration of therapeutics and contrast agents for bioimaging among other applications. Nanogels are usually produced upon irradiation of dilute aqueous polymer solutions. Under these conditions, the polymer radicals formed primarily react via intramolecular radical-radical combination forming intramolecular crosslinks. The manufacturing process is fast and effective and grants excellent control of particle size and simultaneous sterilization of the formed nanogels. Interestingly, primary amino groups and carboxyl groups, useful for (bio)conjugation, are also formed in a dose…
Synthesis and modification of functional polymer nanogels using pulsed-electron beam ionising irradiation
2016
Nanogels made of bio-compatible hydrophilic polymers can be used in various medical applications such as targeted nano-medicine delivery and imaging agents. Intravenously introduced nanogel-drug conjugates may accumulate in tumors through the enhanced permeability and retention effect. We present our latest results on the synthesis and kinetic analysis of two nanogel systems (1) poly)vinyl pyrrolidone) (PVP) and (2) gelation/polyethylene glycol (GEL/PEG) using ionizing irradiation (g-ray, electron beams). The characteristics of nanogels depend on the radiation synthesis parameters (e.g. total dose, pulse repetition rate, etc.). Specifically, one may tune the parameters to promote the crossl…
Computer simulation of ferroelectric property changes in PLZT ceramics under neutron irradiation
2001
The response of ferroelectric materials to high energy irradiation is of great interest because of their possible application in radiation environments such as thermonuclear reactors. In the present work a physical model for the defect evolution in PLZT ceramics under neutron irradiation and annealing is proposed. The influence of the defect system on the ferroelectric properties of these materials has been investigated. Satisfactory agreement between the theoretical estimated oxygen defect concentration after irradiation and annealing and the experimentally determined polarization has been obtained.
Pulsatile protein release and protection using radiation-crosslinked polypeptide hydrogel delivery devices
2011
Abstract In the recent years recombinant technology has identified numerous protein based therapeutics. Their effective delivery, though, can be challenging due to the poor stability of most proteins along their pathway to the target site in the body. Hydrogels have been identified as good candidates for protein encapsulation and delivery thanks to both material and manufacturing process advantages. In this work we propose high energy irradiation as a synthetic methodology of choice to engineer hydrogel-based delivery devices for encapsulation and pulsatile release of proteins, triggered by pH, and for prevention of their denaturation when encapsulated. In particular, maleic anhydride funct…