Department of Chemical Engineering, University of Alcalá, Alcalá de Henares, Madrid 28871, Spain.
Department of Chemical Engineering, University of Alcalá, Alcalá de Henares, Madrid 28871, Spain; Madrid Institute for Advanced Studies of Water (IMDEA Agua), Parque Científico Tecnológico, Alcalá de Henares, Madrid E-28805, Spain.
Sci Total Environ. 2016 Sep 1;563-564:912-20. doi: 10.1016/j.scitotenv.2015.10.072. Epub 2015 Oct 31.
Electrospun cellulose acetate composites containing silver and copper nanoparticles supported in sepiolite and mesoporous silica were prepared and tested as fungistatic membranes against the fungus Aspergillus niger. The nanoparticles were in the 3-50nm range for sepiolite supported materials and limited by the size of mesopores (5-8nm) in the case of mesoporous silica. Sepiolite and silica were well dispersed within the fibers, with larger aggregates in the micrometer range, and allowed a controlled release of metals to create a fungistatic environment. The effect was assessed using digital image analysis to evaluate fungal growth rate and fluorescence readings using a viability stain. The results showed that silver and copper nanomaterials significantly impaired the growth of fungi when the spores were incubated either in direct contact with particles or included in cellulose acetate composite membranes. The fungistatic effect took place on germinating spores before hyphae growth conidiophore formation. After 24h the cultures were separated from fungistatic materials and showed growth impairment only due to the prior exposure. Growth reduction was important for all the particles and membranes with respect to non-exposed controls. The effect of copper and silver loaded materials was not significantly different from each other with average reductions around 70% for bare particles and 50% for membranes. Copper on sepiolite was particularly efficient with a decrease of metabolic activity of up to 80% with respect to controls. Copper materials induced rapid maturation and conidiation with fungi splitting in sets of subcolonies. Metal-loaded nanomaterials acted as reservoirs for the controlled release of metals. The amount of silver or copper released daily by composite membranes represented roughly 1% of their total load of metals. Supported nanomaterials encapsulated in nanofibers allow formulating active membranes with high antifungal performance at the same time minimizing the risk of nanoparticle release into the environment.
静电纺丝纤维素醋酸酯复合材料，含有银和铜纳米粒子负载于海泡石和介孔硅中，被制备并测试作为抗黑曲霉真菌的抑菌膜。纳米粒子的尺寸在 3-50nm 之间，适用于负载于海泡石的材料，而在介孔硅的情况下，纳米粒子的尺寸则受限于介孔（5-8nm）的大小。海泡石和硅纳米纤维内分散良好，微米级的大团聚体，允许金属的可控释放，从而创造抑菌环境。采用数字图像分析评估真菌生长率，并用荧光染色评估真菌活力来评估效果。结果表明，当孢子与颗粒直接接触或包含在醋酸纤维素复合膜中孵育时，银和铜纳米材料显著抑制了真菌的生长。抑菌作用发生在发芽孢子上，而在菌丝生长和分生孢子形成之前。24h 后，将培养物与抑菌材料分离，仅由于先前的暴露而显示出生长受损。所有颗粒和膜都对未暴露的对照具有重要的生长抑制作用。负载铜和银的材料的效果彼此之间没有显著差异，裸颗粒的平均减少率约为 70%，而膜的平均减少率约为 50%。负载于海泡石上的铜尤其有效，相对于对照物，其代谢活性降低了 80%。铜材料诱导真菌快速成熟和分生孢子形成，将真菌分裂成亚菌落。负载金属的纳米材料充当金属的受控释放的储库。复合膜每天释放的银或铜的量约为其金属总负载量的 1%。封装在纳米纤维中的负载纳米材料的支持物允许在最小化纳米颗粒释放到环境中的风险的同时，制备具有高抗真菌性能的活性膜。
