즉시방출제제 DDS 시스템에서 약물흡수에 영향을 주는 요인과 지연방출 제제

소개글

즉시방출제제 DDS 시스템에서 약물흡수에 영향을 주는 요인과 지연방출 제제에 대한 보고서 자료입니다.

목차

1. Immediate-release drug delivery system : Increasing the permeability and absorption of drugs
Introduction
1) The Biopharmaceutics Classification System
Predicting low drug absorption
Using the Biopharmaceutics Classification System
Barrier to drug absorption
Strategies to overcome the barriers to drug absorption

2. Delayed-release drug delivery system
1) small intestine-specific delivery
2) Mechanisms of enteric coatings
3) The coating process
Examples of polymers used for enteric coating (p.75)
Colon-specific drug delivery

본문내용

alate (HPMCAP : hypromellose phthalate)
-cellulose derivatives
- phtalyl content 24% dissolve at PH5 , 31% dissolve at PH5.5
- without plasticiser (only used for risk of crack)
- soluble in ethanol:water = 80:20
(3) Poly (vinyl acetate phtalate, PVAP)
activated phthalic acid formphthalic anhydride form
- polyvinyl derivatives
- plasticiser : diethyl phthalate, polyethylene glycol 400, glyceryl triacetate
(4) Polymethacrylates
- Eudragit L : methacrylic acid : methlymethacrylate = 1:1
- Eudragit S : methacrylic acid : methlymethacrylate = 1:2
Colon-specific drug delivery
●advatage
many drugs are more favorable for colon than small intestine
enzyme activity is lower than in small intestine
●disadvatage
hepatic fist-pass metabolism
a possible presystemic drug metabolism
●strategies
(1) enzyme triggered release
colon-targeted delivery system (CODES)
combination of enzyme-triggered and PH- dependent
- core tablet : consist of polymer lactulose,
lactulose is dissolved in small intestine
- acid-soluble polymer : Eudragit E,
in colon lactulose is degraded by enterobacteria into organic acids that lead to degradtaion of acid-soluble polymer
- enteric coating : Eudragit L
prodrugs for enzyme-triggered release
sulfasalazine = sulfapyridine + 5-aminosalicylic acid
(toxic) (effective)
olsalazine = 5-aminosalicylic acid + 5-aminosalicylic acid
(2) PH- controlled release
- poly(methacrylate) derivate:
Eudragit L and S : soluble PH 5.5-6.5,
Eudragit FS 20D : soluble PH7, free COOH : ester = 1:10
(3) Time controlled release
- Eudracol system
pellet- SR coating enteric coating
(4) Telescopic capsule as a delayed-delivery osmotic device
two chamber : active ingrediant, osmotic engine
참고문헌
Pharmaceutics drug delivery and targeting , Second Edition, Ybone perrie and Thomas rade

키워드

Delayed-release,   Immediate-release,   drug delivery system,   permeability,   absorption,   drug,   즉시방출,   지연방출,   DDS,   즉시방출과 지연방출