Naltrexone, release, poly

Release of naltrexone. The release of naltrexone using poly (ortho ester) II has already been discussed in Sect. 4.2.5. Since it was not possible to form highly loaded devices that had useful mechanical properties due to an interaction between naltrexone and the polymer at the device fabrication temperatures, it was decided to use the ductile polymer since naltrexone could be mixed into the polymer at room temperature and with appropriate mechanical mixing, high drug loadings could be achieved. 

FIGURE 16A Daily rate of release of naltrexone from a poly-e-caprolactone-co-lactic acid capsule (reservoir device) under in vitro conditions. (From Ref. 89.)... 

Although the Alza poly(ortho ester) system has never been structurally identified other than by its tradename Chronomer, and later Alzamer, several publications provide a general description of the use of the polymer for the release of naltrexone (46) and contraceptive steroids (47. 48, 49). 

Maa, YF. and Heller, J. (1990) Controlled release of naltrexone pamoate from linear poly(ortho esters) J. Controlled Release, 14, 21. 

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