Advanced Engineering Platform, Mechanical Engineering Discipline, School of Engineering, Monash University Malaysia , Selangor 47500, Malaysia.
Department of Physics and Chemistry, University of Palermo , Viale delle Scienze, pad. 17, Palermo 90128, Italy.
ACS Appl Mater Interfaces. 2017 May 24;9(20):17476-17488. doi: 10.1021/acsami.7b04297. Epub 2017 May 15.
Pectin bionanocomposite films filled with various concentrations of two different types of halloysite nanotubes were prepared and characterized in this study as potential films for food packaging applications. The two types of halloysite nanotubes were long and thin (patch) (200-30 000 nm length) and short and stubby (Matauri Bay) (50-3000 nm length) with different morphological, physical, and dispersibility properties. Both matrix (pectin) and reinforcer (halloysite nanotubes) used in this study are considered as biocompatible, natural, and low-cost materials. Various characterization tests including Fourier transform infrared spectroscopy, field emission scanning electron microscopy, release kinetics, contact angle, and dynamic mechanical analysis were performed to evaluate the performance of the pectin films. Exceptional thermal, tensile, and contact angle properties have been achieved for films reinforced by patch halloysite nanotubes due to the patchy and lengthy nature of these tubes, which form a bird nest structure in the pectin matrix. Matauri Bay halloysite nanotubes were dispersed uniformly and individually in the matrix in low and even high halloysite nanotube concentrations. Furthermore, salicylic acid as a biocidal agent was encapsulated in the halloysite nanotubes lumen to control its release kinetics. On this basis, halloysite nanotubes/salicylic acid hybrids were dispersed into the pectin matrix to develop functional biofilms with antimicrobial properties that can be extended over time. Results revealed that shorter nanotubes (Matauri Bay) had better ability for the encapsulation of salicylic acid into their lumen, while patchy structure and longer tubes of patch halloysite nanotubes made the encapsulation process more difficult, as they might need more time and energy to be fully loaded by salicylic acid. Moreover, antimicrobial activity of the films against four different strains of Gram-positive and Gram-negative bacteria indicated the effective antimicrobial properties of pectin/halloysite functionalized films and their potential to be used for food packaging applications.
本文制备了填充有两种不同类型海泡石纳米管的不同浓度的果胶生物纳米复合材料薄膜，并对其进行了研究，作为潜在的食品包装应用薄膜。这两种类型的海泡石纳米管具有不同的形态、物理和分散性能，分别为长而细的（片状）（200-30000nm 长度）和短而粗的（马塔瑞湾）（50-3000nm 长度）。本研究中使用的基质（果胶）和增强剂（海泡石纳米管）均被认为是生物相容的、天然的和低成本的材料。进行了各种特性测试，包括傅里叶变换红外光谱、场发射扫描电子显微镜、释放动力学、接触角和动态力学分析，以评估果胶膜的性能。由于这些管的片状和长形性质，片状海泡石纳米管增强的膜具有出色的热学、拉伸和接触角性能，在果胶基质中形成鸟巢结构。马塔瑞湾海泡石纳米管在低浓度甚至高浓度下都能均匀分散在基质中。此外，水杨酸作为一种生物杀灭剂被包裹在海泡石纳米管的管腔中，以控制其释放动力学。在此基础上，将海泡石纳米管/水杨酸杂化物分散到果胶基质中，开发具有抗菌性能的功能性生物膜，可以随着时间的推移而扩展。结果表明，较短的纳米管（马塔瑞湾）具有将水杨酸更好地封装到其管腔中的能力，而片状结构和较长的片状海泡石纳米管使封装过程更加困难，因为它们可能需要更多的时间和能量才能被水杨酸完全加载。此外，薄膜对四种不同的革兰氏阳性和革兰氏阴性细菌的抗菌活性表明，果胶/海泡石功能化薄膜具有有效的抗菌性能，并且可能用于食品包装应用。
