- 學位論文
以靜電噴霧技術製備尤加利精油/海藻酸鈣微膠囊
Preparation of Eucalyptus Oils/ Calcium Alginate Microcapsules by Electrospray Technique
摘要
本研究主要係用尤加利精油為芯材、海藻酸鈉為殼材，利用微膠囊化之孔口法原理，以氯化鈣溶液中的鈣離子和海藻酸鈉膠體溶液進行固化反應，產生海藻酸鈣殼層並結合靜電噴霧技術之可以製備微米∼奈米級液滴且液滴粒徑均一性高的特點，製備尤加利精油/海藻酸鈣微膠囊。探討微膠囊的成形性、粒徑分布、包覆率及釋放率。 本實驗分為三大部分，分別為（I）靜電噴霧乳化液配置：利用乳化作用來提高精油與海藻酸鈉之間的安定性，並找出合適之O/W/SLS乳化液配置比例。由實驗結果可發現界面活性劑（SLS）的添加有助於乳化安定性的增加，將乳化液進行離心和溫度穩定性試驗分析後，得知最佳穩定性的乳化液比例O/W/SLS＝1.00/1.00/4.00，此乳化液經離心20.00分鐘後無油水分離的現象；於室溫保存其乳化安定性為6天，若將乳化液放置低溫保存，乳化液安定性可達11天。 （II）海藻酸鈣微膠囊製備：此部分實驗利用不同的靜電噴霧參數條件進行海藻酸鈣微膠囊的製備，探討靜電噴霧參數對微膠囊的成形性和粒徑分布之關係，並找出最佳化的靜電噴霧參數條件。由實驗結果發現最佳靜電噴霧條件：工作電壓為20.00 kV、T-C距離（針頭到收集板距離）為5.00 cm、進料速率為1.00 mL/hr.，此條件所得微膠囊之殼層成形性完整且平均粒徑為314.43 μm。 （III）尤加利精油/海藻酸鈣微膠囊製備：此部分實驗為尤加利精油的包覆率及釋放率之探討。由實驗結果分析可以得知，不同O/W/SLS乳化液比例對尤加利精油的包覆率僅造成微量影響，當界面活性劑添加量由0.20 mL提高到0.80 mL時，其精油包覆率從90.50%增加至93.57%。至於靜電噴霧參數（工作電壓）的改變造成微膠囊粒徑大小的明顯變化，但並不會影響尤加利精油的包覆率，工作電壓從0.00 kV∼20.00 kV時，其精油平均包覆率多落在91.36%∼91.75%。
並列摘要
In this work, Eucalyptus Oil and Sodium Alginate are used as a core and wall membrane material for the production of Calcium Alginate encapsulated Eucalyptus Oil microcapsules, which has been done by the orifice method. It is possible to prepare the micron to nano-scale microcapsules and uniform particle size by combining the Electro spray technique with orifice method. This work investigates the formation and particle size distribution of microcapsules, the encapsulation efficiency of the Eucalyptus Oil, and the release behavior of the encapsulated Eucalyptus Oil. Here the experimental work is divided into three parts which are electrospray emulsion configuration, preparation of calcium alginate microcapsules and preparation of eucalyptus oils / calcium alginate microcapsules. (I) Electrospray emulsion configuration: From the experimental results, it can be found that the emulsification is improve the stability of the Eucalyptus Oil with the Sodium Alginate. The emulsion stability increases when the amount of surfactant (SLS) increases. From centrifugation stability test analysis and temperature stability test analysis, it has been predicted that the best stability of the emulsion ratio (O/W/SLS) is 1.00:1.00:4.00. The emulsion does not show the phenomenon of oil-water separator after 20.00 minutes centrifugation process. It can be preserved the emulsion stability at room temperature for 6 days, and emulsion stability up to 11 days is also possible at low-temperature. (II) Preparation of Calcium Alginate microcapsules: This part is discussing the electrospray parameters on the formability of the microcapsules and the relationship of particle size distribution, and also identifies the best electrospray parameter conditions for capsule production. From the results, the best electrospray conditions was found as follows: operating voltage is 20.00 kV, T-C distance (needle to the collector plate distance) is 5.00 cm, the feed rate is 1.00 mL/hr., This condition is produce the complete shell formation on microcapsule with the average particle sizes of 314.43 μm. (III) Preparation of Eucalyptus Oils / Calcium Alginate microcapsules: it explains the experimental procedure for measuring the encapsulation efficiency of Eucalyptus Oil and the release behavior of the encapsulated Eucalyptus Oil. From the experimental results, different emulsion proportion (O/W/SLS) of Eucalyptus Oil coating was caused by only micro effects. When the amount of surfactant (SLS) is increased from 0.20 mL to 0.80 mL , the encapsulation efficiency of Eucalyptus Oil is increase from 90.10 % to 93.90 %. The electrospray parameters (ex:operating voltage) change caused the significant changes in particle size of the microcapsules, but does not affect the coating of Eucalyptus Oil for the operating voltage 0.00 kV to 20.00 kV. Its average encapsulation efficiency falls 91.50 % to 91.70 %.