NMR spectroscopy and imaging studies of pharmaceutical tablets made of starch

Modified polysaccharides such as high amylose starch are used as excipient in controlled drug release technology. Crosslinked high amylose starch is a hydrophilic matrix used for the sustained release of drugs. Tablets using modified hybrid starch as excipient display zero-order release over 2–24 h. A release over 3–4 weeks was observed when the modified starch is used as an implant. The use of starch in controlled release system is appealing because it could be easily metabolized in the human body. We review here the use of NMR imaging and solid state 13C spectroscopy in the study of the various factors influencing drug release in such systems.