Polysaccharides are ideal green synthetic raw materials to improve the biocompatibility of metal nanoparticles. However, polysaccharides generally have weak reducibilities, being challenging supports for the direct preparation of Ag nanoparticles. In this work, gold nanoclusters were prepared using a triple helix glucan (Lentinan) via microwave-assisted synthesis and subsequently employed as seeds for the synthesis of a series of Ag-Au alloy nanoparticles (Ag-AuNPs). The results showed that gold nanoclusters can remarkably speed up the preparation of Ag-AuNPs without the addition of any other chemicals. The particle size of Ag-AuNPs increased at increasing Ag contents in the alloy. Results of UV-vis, transmission electron microscope (TEM) and inductively coupled plasma mass spectrometry (ICP-MS) suggested that Ag⁺ was quickly reduced to irregular silver nanoparticles (with gold nanoparticles as seeds), then gradually form more regular nano-alloys. Additionally, X-ray diffraction (XRD) and zeta potential results suggested that Ag-AuNPs could entrap the hydrophobic cavity of triple helix polysaccharides during the renaturation process. The nanocomposites exhibited good antifungal activity and low cytotoxicity to RAW264.7, Hela and LO2 cell lines in vitro.

多糖是理想的绿色合成原料，可提高金属纳米粒子的生物相容性。然而，多糖通常具有弱的还原性，是直接制备Ag纳米颗粒的有挑战性的支持。在这项工作中，使用三螺旋葡聚糖（Lentinan）通过微波辅助合成制备了金纳米团簇，随后将其用作种子以合成一系列Ag-Au合金纳米颗粒（Ag-AuNPs）。结果表明，金纳米团簇可以显着加快Ag-AuNPs的制备，而无需添加任何其他化学物质。随着合金中Ag含量的增加，Ag-AuNPs的粒径增加。紫外可见，透射电子显微镜（TEM）和电感耦合等离子体质谱（ICP-MS）结果表明，Ag ⁺很快被还原为不规则的银纳米颗粒（以金纳米颗粒为种子），然后逐渐形成更规则的纳米合金。此外，X射线衍射（XRD）和Zeta电位结果表明，在复性过程中，Ag-AuNPs可能捕获三螺旋多糖的疏水腔。该纳米复合材料在体外对RAW264.7，Hela和LO2细胞系表现出良好的抗真菌活性和低细胞毒性。