促進綠茶萃取物生體可利用率之纖維素經皮遞藥系統

Improvement of the Bioavailability of Green Tea Extract in Cellulose-based Transdermal Delivery System

何怡儂(Yi-Nung Ho)

指導教授 ： 謝明發

中原大學/工學院/醫學工程研究所/碩士(2009年)

https://doi.org/10.6840/cycu200901344

摘要

本研究製備一種利用聚乙二醇-己內酯改質親水性纖維素作為經皮遞藥系統並搭載綠茶萃取物，比較此系統與口服綠茶萃取物生體可利用率的差異。本研究內容分為四部份: (一)藉由有機溶劑萃取綠茶中的兒茶素，利用高效能液相層析儀定量及定性分析，測試綠茶萃取物在不同濃度與不同反應時間下抗氧化能力，(二)製備不同分子量的聚乙二醇-聚己內酯接枝於纖維素(E50C36-HEC、E50C80-HEC)和純纖維素(HEC)三種貼片，包含材料顯微結構性質分析及接觸角量測，並以體外藥物釋放裝置評估綠茶萃取物滲透豬皮之能力，(三)與巨噬細胞共培養做抗發炎之體外評估，(四)比較貼片與口服兩種不同給藥途徑，綠茶萃取物在大鼠模式下之藥物動力學。本研究以氯仿和乙酸乙酯萃取後可得到純度84 %的綠茶萃取物，同時咖啡因含量為0.09 %，當綠茶萃取物在低濃度0.05 mg/mL與0.01 mg/mL時，自由基清除率達90 %以上，且在3分鐘內自由基清除率達到穩定狀態。在掃描式電子顯微鏡下觀察到，聚乙二醇-己內酯改質後纖維素薄膜表面粗糙度增加，在體外藥物釋放測試結果發現，E50C36-HEC、E50C80-HEC和HEC搭載1.5 mg/cm2綠茶萃取物在48小時後滲透量分別可達到0.8、0.15和0.04 mg/mL。在抗發炎反應中，若先加入4.58 μg/mL之綠茶萃取物與活化後的巨噬細胞共培養24小時，能夠抑制一氧化氮的產生；而先以脂多醣刺激巨噬細胞後再加入綠茶萃取物則沒有抑制效果。第四部份，口服200 mg/kg綠茶萃取物經過24小時後，血漿中EGCG的曲線下面積為34.22 μg．hr/mg；平均血漿中最高濃度為22.7 μg/mg；搭載綠茶萃取物的E50C36-HEC、E50C80-HEC、HEC三種貼片，平均曲線下面積為356.24±3.24、293.45±4.68、245.08±14.65 μg．hr/mg；平均血漿中最高濃度為19.03、16.40、14.66 μg/mg；E50C36-HEC貼片的相對生體可利用率為10.4。未來將探討纖維素之貼片搭載抗氧化及抗炎性之綠茶萃取物，應用於傷口敷料，達到加速傷口癒合的效果。

關鍵字

生物利用率 ； 兒茶素 ； 抗氧化 ； 經皮遞藥系統

並列摘要

In this present study, we used mPEG-PCL-graft-2-hydroxycellulose (mPEG-PCL-g-HEC) as a penetration matrix for skin delivery system of anti-oxidative catechins extracted from green tea in order to compare bioavailability of this system and oral administration. The study was divided into four parts: In the first part, different organic solvents were used to extract the catechins from green tea. High-performance liquid chromatography (HPLC) was used to perform qualitative and quantitative analyses of catechins. The anti-oxidant capacity of catechins from green tea extract was evaluated by DPPH radical experiment. In the second part, preparation and characterization of copolymer thin films were performed (E50C36-HEC, E50C80-HEC, HEC). The scanning electron microscopy (SEM) was used to observe the microstructure of patches. Moreover, in-vitro catechin release from prepared patches was obtained through porcine skin. In the third part, the safety evaluations of catechins were confirmed by nitric oxide (NO) and tretrazolium (MTT) assay on macrophages. The cell survival and co-culture were demostrated for anti-inflammatory response. Finally, animal study was examined in rats to measure pharmacokinetics of green tea extract. The HPLC results confirmed that a large amount of caffeine was removed from green tea extract after two steps of chloroform and ethyl acetate extraction. The green tea extract content was high purity with 84 % of EGCG and 0.09 % of caffeine. The radical scavenging activity of the extract was up to 80 % at 0.05 mg/mL and 0.01 mg/mL and the radical scavenging activity able to achieve 98 % within 10 minutes. By adding the PEG-PCL polymer, surface of film was rougher than that of pure cellulose. The drug loading content of E50C36-HEC was 1.5 mg/cm2 and the in-vitro drug release was found to be 0.8 mg/mL for 48 h. In addition, anti-inflammatory response, 4.58 μg/mL of green tea extracts and activated macrophages were co-cultured showed that NO production was generated. Finally, animal experiments were conducted through the oral and transdermal administration. In the oral administration, the green tea extract AUC was 34.22 μg．hr/mg and Cmax was 22.7 μg/mg. In contrast, in the transdermal administration, the green tea extract AUC were 347.21, 293.45 and 245.05 μg hr/mg, and Cmax were 19.03、16.40、14.66 μg/mg for E50C36-HEC, E50C80-HEC and HEC patches, respectively. 10.4 improved relative bioavailability was observed in the transdermal administration of cactechin. We expected that green tea extract in cellulose-base transdermal delivery system will apply to the wound dressing to accelerate the wound healing effect.

並列關鍵字

catechin ； bioavailab ； anti-oxidative ； transdermal delivery

參考文獻

6. 黃志煜，吳志鴻，張振生，葉永廉，張上鎮，製程與採收季節對茶葉抽出物抗氧化活性之影響，國立臺灣大學農學院實驗林管理處 2003;17(4):231-237。

8. Yang C, Chen L, Lee M, Balentine D, Kuo M, Schantz S. Blood and urine levels of tea catechins after ingestion of different amounts of green tea by human volunteers. Cancer Epidemiology Biomarkers & Prevention 1998;7(4):351-354.

3. Duchin KL, McKinstry DN, Cohen AI, B.HMigdalof. Pharmacokinetics of captopril in healthy subjects and in patients with cardiovascular diseases. Clinical pharmacokinetics 1988;14:241-256.

4. Dong H, Xu Q, Li Y, Mo S, Cai S, Liu L. The synthesis of biodegradable graft copolymer cellulose-graft-poly(L-lactide) and the study of its controlled drug release. Colloids Surf B Biointerfaces 2008;66(1):26-33.

5. Yang MH, Wang CH, Chen HL. Green, oolong and black tea extracts modulate lipid metabolism in hyperlipidemia rats fed high-sucrose diet The Journal of Nutritional Biochemistry 2001;12(1):14-20.