天堂国产午夜亚洲专区-少妇人妻综合久久蜜臀-国产成人户外露出视频在线-国产91传媒一区二区三区

當(dāng)前位置:主頁(yè) > 科技論文 > 材料論文 >

EGCG-CS-PAA納米粒的制備及其生物活性研究

發(fā)布時(shí)間:2018-10-19 10:41
【摘要】:EGCG陛質(zhì)很不穩(wěn)定,易受光、氧、溫度、pH、金屬離子等外界因素的影響從而嚴(yán)重限制了其應(yīng)用的前景。在參考前人研究的基礎(chǔ)上,發(fā)現(xiàn)殼聚糖納米技術(shù)能較好的保護(hù)EGCG免于遭受惡劣環(huán)境的破壞。殼聚糖納米粒包埋EGCG后,由于納米粒的優(yōu)越特性,使得EGCG生物功效得到提高,同時(shí)EGCG的釋放也變緩,從而提高了EGCG的利用效率。 在本研究中,利用殼聚糖CS和聚天冬氨酸PAA之間離子交聯(lián)制備CS-PAA納米粒載體,以此裝載EGCG,然后對(duì)EGCG-CS-PAA納米粒的穩(wěn)定性和生物活性等做了相關(guān)研究。研究發(fā)現(xiàn),不同的制備參數(shù)能顯著影響納米粒的粒徑、分散指數(shù)和Zeta電位等特性。當(dāng)質(zhì)量比(CS/PAA)為1.0、pH為3.5、反應(yīng)時(shí)間為60min、CS分子量為3-5KDa和PAA分子量為30-50KDa時(shí),制備出的殼聚糖納米粒的粒徑和表面電荷等物理特征為最佳。同時(shí),在該制備參數(shù)下制備出的EGCG-CS-PAA納米粒的包封率達(dá)到25%,載藥量為344.1mg/kg,且其粒徑比未包埋EGCG的CS-PAA納米粒大些。 EGCG-CS-PAA納米粒的體外釋放研究表明在模擬胃環(huán)境(pH=2.5-4.0)下從納米粒中釋放出來(lái)的EGCG含量較少;在模擬腸環(huán)境(pH=6.0-7.4)下,納米顆粒容易發(fā)生降解從而迅速釋放EGCG。通過(guò)采用FRAP和DPPH法對(duì)EGCG-CS-PAA納米粒的抗氧化活性進(jìn)行分析,兩者都顯示納米體系對(duì)EGCG的抗氧化活性具有良好的保護(hù)作用。同時(shí)EGCG-CS-PAA納米體系能在高溫、堿性等惡劣環(huán)境下對(duì)EGCG起到較好的保護(hù)作用。 白兔體內(nèi)試驗(yàn)結(jié)果顯示,相比于自由的EGCG, EGCG-CS-PAA納米粒在預(yù)防白兔動(dòng)脈粥樣硬化及其降血脂功效方面得到明顯的提高。在EGCG納米粒小鼠急性試驗(yàn)中,在實(shí)驗(yàn)最大劑量(60mL/kg)范圍內(nèi),雌雄小鼠均未出現(xiàn)死亡及異常情況,且給藥后對(duì)小鼠的體重也無(wú)顯著影響。同時(shí),細(xì)胞毒性試驗(yàn)結(jié)果也表明EGCG-CS-PAA納米粒及所制備的材料均為無(wú)毒安全的。 本研究結(jié)果表明,CS-PAA納米體系可以作為如EGCG等不穩(wěn)定功能性藥物的載體,有效保護(hù)其生物穩(wěn)定性,為EGCG在醫(yī)藥食品等領(lǐng)域的應(yīng)用開拓新的途徑。
[Abstract]:EGCG is unstable and vulnerable to light, oxygen, temperature, pH, metal ions and other external factors, which seriously limits its application prospects. On the basis of previous studies, it was found that chitosan nanotechnology could protect EGCG from severe environmental damage. After EGCG was encapsulated by chitosan nanoparticles, because of the superior properties of nanoparticles, the biological efficacy of EGCG was improved, and the release of EGCG was slowed down, thus improving the utilization efficiency of EGCG. In this study, the carrier of CS-PAA nanoparticles was prepared by ion crosslinking between chitosan CS and polyaspartic acid PAA, and then the stability and bioactivity of EGCG-CS-PAA nanoparticles were studied by loading EGCG,. It is found that different preparation parameters can significantly affect the particle size, dispersion index and Zeta potential. When the mass ratio (CS/PAA) is 1.0 渭 g pH is 3.5, the reaction time is 60 min CS molecular weight is 3-5KDa and PAA molecular weight is 30-50KDa, the size and surface charge of the prepared chitosan nanoparticles are the best. meanwhile The encapsulation efficiency of EGCG-CS-PAA nanoparticles prepared under this preparation parameter is 25mg / kg, the drug loading is 344.1 mg / kg, and its diameter is larger than that of CS-PAA nanoparticles without EGCG. The in vitro release study of EGCG-CS-PAA nanoparticles shows that under simulated gastric environment (pH=2.5-4.0), The content of EGCG released from nanoparticles was less. Under simulated intestinal environment (pH=6.0-7.4), nanoparticles are liable to degrade and release EGCG. rapidly. The antioxidant activity of EGCG-CS-PAA nanoparticles was analyzed by FRAP and DPPH. Both of them showed that the nanoparticles had good protective effect on the antioxidant activity of EGCG. At the same time, EGCG-CS-PAA nanosystem can protect EGCG in high temperature and alkaline environment. The results showed that compared with the free EGCG, EGCG-CS-PAA nanoparticles, the effect of preventing atherosclerosis and lowering blood lipids in white rabbits was significantly improved. In the acute test of EGCG nanoparticles mice, in the range of maximum experimental dose (60mL/kg), there was no death and abnormality in both male and female mice, and there was no significant effect on the body weight of mice after administration of the drug. At the same time, the results of cytotoxicity test also showed that the EGCG-CS-PAA nanoparticles and the prepared materials were nontoxic and safe. The results show that CS-PAA nanosystem can be used as a carrier of unstable functional drugs such as EGCG, protect its biological stability effectively, and open up a new way for the application of EGCG in the field of medicine and food.
【學(xué)位授予單位】:浙江工商大學(xué)
【學(xué)位級(jí)別】:碩士
【學(xué)位授予年份】:2015
【分類號(hào)】:TQ460.1;TB383.1

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 王佩華;趙大偉;;茶多酚在食品工業(yè)中的應(yīng)用[J];安徽農(nóng)業(yè)科學(xué);2010年33期

2 魏決;天然抗氧化劑茶多酚的提取及抗氧化試驗(yàn)[J];成都大學(xué)學(xué)報(bào)(自然科學(xué)版);1998年02期

3 郭炳瑩,程啟坤;茶湯組分與金屬離子的絡(luò)合性能[J];茶葉科學(xué);1991年02期

4 鄭紅發(fā);黃亞輝;黃懷生;陳曉陽(yáng);;高EGCG茶資源篩選及適制地域研究[J];福建茶葉;2007年02期

5 汪冰,豐偉悅,趙宇亮,邢更妹,柴之芳,王海芳,賈光;納米材料生物效應(yīng)及其毒理學(xué)研究進(jìn)展[J];中國(guó)科學(xué)(B輯 化學(xué));2005年01期

6 孟幻;陳真;趙宇亮;;部分納米材料的納米生物學(xué)效應(yīng)研究[J];基礎(chǔ)醫(yī)學(xué)與臨床;2006年07期

7 吳立明;習(xí)溫瑜;管正紅;;殼聚糖納米粒制備的研究進(jìn)展[J];齊魯藥事;2008年11期

8 史一杰;程剛;;納米制劑生物安全性評(píng)價(jià)研究進(jìn)展[J];沈陽(yáng)藥科大學(xué)學(xué)報(bào);2010年12期

9 金麗霞;;納米藥物載體的研究及臨床應(yīng)用[J];中國(guó)組織工程研究與臨床康復(fù);2010年08期

10 張宏娟,張燦,平其能;聚合物膠束作為藥用載體的研究與應(yīng)用[J];藥學(xué)進(jìn)展;2002年06期

,

本文編號(hào):2280886

資料下載
論文發(fā)表

本文鏈接:http://sikaile.net/kejilunwen/cailiaohuaxuelunwen/2280886.html


Copyright(c)文論論文網(wǎng)All Rights Reserved | 網(wǎng)站地圖 |

版權(quán)申明:資料由用戶3d4fc***提供,本站僅收錄摘要或目錄,作者需要?jiǎng)h除請(qǐng)E-mail郵箱bigeng88@qq.com