Nanocomposite films were obtained by solution casting method from aqueous solution of bovine gelatin with addition of various concentrations of magnetic iron oxide (MIO) nanoparticles (NPs) (5, 10, 15, and 20% w/w of dry gelatin). The incorporation of MIO NPs improved the mechanical and physical properties of the nanocomposites. The increase in concentration of NPs up to 10% improved barrier and mechanical properties which slightly decreased after increasing the concentration beyond that limit due to particle agglomeration. The scanning electron microscopy and X‐ray diffraction (XRD) were used to evaluate the morphology and crystalline structure of gelatin nanocomposite films, respectively. Gelatin nanocomposites with 20% w/w NPs exhibited the highest antimicrobial activity against Escherichia coli (7.1 ± 0.085 mm) and Staphylococcus aureus (8.22 ± 1.04 mm). Finally, the potential of gelatin/MIO nanocomposites as packaging material was evaluated to extend the shelf life of grapes. The gelatin/MIO nanocomposites can be used as a replacement to non‐biodegradable packaging.

中文翻译：

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掺有磁性氧化铁纳米粒子的明胶纳米复合薄膜可延长葡萄的保质期

通过溶液流延法从牛明胶水溶液中添加各种浓度的磁性氧化铁（MIO）纳米粒子（NPs）（干明胶的5、10、15和20％w / w）获得纳米复合膜。MIO NP的掺入改善了纳米复合材料的机械和物理性能。NPs浓度增加到10％可以改善阻挡层和机械性能，在增加浓度超过该限制后，由于颗粒团聚，其力学性能会略有下降。扫描电子显微镜和X射线衍射（XRD）分别用于评估明胶纳米复合膜的形貌和晶体结构。具有20％w / w NP的明胶纳米复合材料表现出最高的抗大肠杆菌活性（7.1±0.085毫米）和金黄色葡萄球菌（8.22±1.04毫米）。最后，评估了明胶/ MIO纳米复合材料作为包装材料的潜力，以延长葡萄的保质期。明胶/ MIO纳米复合材料可替代不可生物降解的包装。