Gugerli R, Cantana E, Heinzen C, von Stockar U, Marison I W
Laboratory of Chemical and Biochemical Engineering, Swiss Federal Institute of Technology (EPFL), CH-1015 Lausanne, Switzerland.
J Microencapsul. 2002 Sep-Oct;19(5):571-90. doi: 10.1080/02652040210140490.
Alginate-polylysine-alginate (APA) microcapsules are of particular interest for their application as implants or for bioreactor cultures. Although their formation has been widely studied, there is still a lack of quantitative data describing resistance, membrane thickness and permeability. In this study, the quantitative application of a Texture Analyser for the measurement of capsule deformation yielded important results that permit comparison with other polymer systems used for encapsulation. Furthermore, single-membrane and multi-membrane capsules were formed in order to improve the modulation of the capsule properties. For single-membrane capsules, resistance was mostly affected by the incubation time in poly-L-lysine (PLL), the PLL molecular weight and concentration. The increase in resistance from 0.1 +/- 0.01 g/capsules to 2 +/- 0.2 g/capsules was linked to a membrane thickening (35-120 microm) and a decrease in permeability (150 to 40 kD). Thus, it was not possible to modify resistance and membrane permeability independently. Multi-membrane capsules with a resistance comparable to single-membrane capsules could be formed using various combinations of PLL molecular weights, and enabled uncoupling of permeability and resistance properties.
藻酸盐-聚赖氨酸-藻酸盐（APA）微胶囊因其作为植入物或用于生物反应器培养的应用而备受关注。尽管其形成过程已得到广泛研究，但仍缺乏描述其抗性、膜厚度和渗透性的定量数据。在本研究中，使用纹理分析仪对胶囊变形进行定量测量产生了重要结果，可与用于包封的其他聚合物系统进行比较。此外，为了改善胶囊性能的调节，制备了单膜和多膜胶囊。对于单膜胶囊，抗性主要受在聚-L-赖氨酸（PLL）中的孵育时间、PLL分子量和浓度的影响。抗性从0.1±0.01 g/胶囊增加到2±0.2 g/胶囊与膜增厚（35 - 120微米）和渗透性降低（从150 kD降至40 kD）有关。因此，不可能独立改变抗性和膜渗透性。使用PLL分子量的各种组合可以形成具有与单膜胶囊相当抗性的多膜胶囊，并实现渗透性和抗性特性的解耦。
