Application of Fiber-Optic Attenuated Total Reflection-FT-IR Methods for In Situ Characterization of Protein Delivery Systems in Real Time

摘要

ABSTRACT: A fiber-optic coupled attenuated total reflection (ATR)-nFT-IR spectroscopy technique was applied to the study of two differentntherapeutic delivery systems, acid degradable hydrogels and nanopar-nticles. Real time exponential release of a model protein, human serumnalbumin (HSA), was observed from two different polymeric hydrogelsnformulated with a pHsensitive cross-linker. Spectroscopic examinationnof nanoparticles formulated with an acid degradable polymer shell andnencapsulated HSA exhibited vibrational signatures characteristic ofnboth particle and payload when exposed to lowered pH conditions,ndemonstrating the ability of this methodology to simultaneouslynmeasure phenomena arising from a system with a mixture of compo-nnents. In addition, thorough characterization of these pH sensitivendelivery vehicles without encapsulated protein was also accomplishednin order to separate the effects of the payload during degradation.When in situ, real time detection in combination with the ability tonspecifically identify different components in a mixture without involved sample preparation and minimal sample disturbance isnprovided, the versatility and suitability of this type of experiment for research in the pharmaceutical field is demonstrated.