KELES, Hakan, NAYLOR, Andrew, CLEGG, Francis and SAMMON, Chris (2014). Studying the release of hGH from gamma-irradiated PLGA microparticles using ATR-FTIR imaging. Vibrational Spectroscopy, 71, 76-84.
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Attenuated total reflection-Fourier transform infrared (ATR-FTIR) imaging has been applied for the first time to monitor the redistribution and release of hGH from a range of PLGA/PLA microparticles during a set of dissolution experiments at 37 °C in D2O. The effect of gamma-irradiation, a common sterilisation method, on hGH release kinetics from such systems has been demonstrated. Increasing the gamma dose was shown to have a profound influence on the nature of the release mechanism, with higher gamma doses leading to a dramatic increase in the initial burst release followed by a retardation in the sustained release and a lower total level of hGH release over the dissolution experiment. These changes were shown to be the result of a combination of factors; firstly, via scanning electron microscopy (SEM), gamma-irradiation was shown to strongly influence the morphology of the PLGA/PLA microparticles; reducing their overall porosity and reducing the available surface area, whilst forcing some of the entrapped hGH to the microparticle surface. Secondly, from FTIR measurements, gamma-irradiation was shown to increase the number of oxygenated components in the Poloxamer 407 excipient, by a process of chain scission, thereby increasing the strength of interaction between the microparticle and the entrapped hGH.
|Research Institute, Centre or Group:||Materials and Engineering Research Institute > Polymers Nanocomposites and Modelling Research Centre > Polymers, Composites and Spectroscopy Group|
|Depositing User:||Ann Betterton|
|Date Deposited:||12 May 2014 14:20|
|Last Modified:||19 Aug 2015 16:40|
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