Abstract

In spite of the intensive work done on the preparation, characterization and applications of silver nanoparticles, the problems limit its use, still under study. One of these solutions is embedding Ag NPs in natural polymers to decrease aggregation, control its toxicity and size, and to increase its stability as well. In this respect, ionically cross-linked alginate/pectin (ALG/PEC) beads containing silver and clay nanoparticles, with different compositions were prepared. Silver nanoparticles have been obtained with hydrogel networks as nonreactors via in situ reduction of pre-adsorbed silver ions onto (ALG/PEC) beads matrix, using gamma irradiation. The effects of the composition of the two polymers, concentration of CaCl₂ as a crosslinking agent on the formation of cross-linked beads were studied. Characterization of (ALG/PEC) beads, (ALG/PEC)/Ag and (ALG/PEC)/Clay-Ag nanocomposite beads were performed using scanning electron microscopy, transmission electron microscopy and X-ray diffraction (XRD). The XRD pattern obtained confirmed the presence of diffraction peaks related to Ag NPs and nanoclay. The antimicrobial activity, toward different micro-organisms of the prepared nanocomposite beads was examined. The Beads containing both Ag NPs and Nanoclay exhibited the highest antimicrobial activity for the different organisms chosen for the antimicrobial test.

Graphic abstract

中文翻译：

---

Ag和粘土纳米颗粒对γ-射线藻酸盐/果胶珠的抗菌活性的影响

摘要

尽管在银纳米颗粒的制备，表征和应用方面进行了大量工作，但这些问题限制了其用途，目前仍在研究中。这些解决方案之一是将Ag NPs嵌入天然聚合物中，以减少聚集，控制其毒性和尺寸并增加其稳定性。在这方面，制备了具有不同组成的包含银和粘土纳米颗粒的离子交联的藻酸盐/果胶（ALG / PEC）珠。通过使用γ射线将预先吸附的银离子原位还原到（ALG / PEC）珠粒基质上，已以水凝胶网络作为非反应剂获得了银纳米颗粒。两种聚合物的组成，CaCl ₂浓度的影响对作为交联剂的交联珠的形成进行了研究。（ALG / PEC）珠，（ALG / PEC）/ Ag和（ALG / PEC）/ Clay-Ag纳米复合珠的表征使用扫描电子显微镜，透射电子显微镜和X射线衍射（XRD）进行。获得的XRD图谱证实了与Ag NP和纳米粘土有关的衍射峰的存在。检查了所制备的纳米复合材料珠对不同微生物的抗菌活性。含有银纳米颗粒和纳米粘土的珠子对选择进行抗菌测试的不同生物表现出最高的抗菌活性。

图形摘要