For the administration of narcotic antagonist with short half-life and low patient compliance, the sustained release system, using biodegradable matrix is effective. Polyphosphazenes are of considerable interest as biodegradable matrix systems
for
controlled release of drugs, In this study biodegradable polyphosphazenes available for the sustained release implantable device were synthesized, andtheir application was examined. Poly[dichlorophosphzene] was synthesized solution polymerization
method
and confirmed with IR spectrum. Poly(bis (ethyl glycinate) phosphazene) and poly[(diethyl glutamate)-co(ethyl glycinate) phosphazene] were then produced by substitution of amino acid alkyl esters for chloride side groups. Using these polymers,
the
implantable devices of 1mm thickness and 10×10 mm size containing naloxone hydrochloride were prepared and their release and degradation profiles were measured. In the case of poly[bis(ethyl glcinate) phosphazene] with swelling characteristics,
degradation rate was slower than the release rate, showing that the release rate is partly dependent on the swelling rate. In contrast, the degradation rate of poly[(diethyl glutamate)-co-(ethyl glycinate)phosphazene] matrix was identical with
release
rate of naloxone hydrochloride. On the basis of these results, it is expected that these polymers can be applied to sustained release implantable systems delivering narcotic antagonist.
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