The studies on the applications of konjac glucomannan have been extended greatly from food and food additives to various fields [28, 29]. Herein, we explore the use of KGM in the preparation of nanosized materials and thus further promote its application in nanotechnology. BIIB057 In the present study, konjac glucomannan was introduced for the facile synthesis of gold nanoparticles, both as reducing agent and stabilizer (Figure  1). The synthesized gold nanoparticles were characterized in detail by transmission electron microscopy (TEM), X-ray diffraction (XRD), dynamic light

scattering (DLS), and Fourier transform infrared (FTIR) spectroscopy. Furthermore, the catalytic activity of the gold nanoparticles was investigated by the reduction of p-nitrophenol (4-NP) to p-aminophenol (4-AP). It should be noted that Konjac glucomannan, as an abundant natural polysaccharide, could be easily gained from Konjac plant tubers at low cost. Meanwhile, the gold nanoparticles reduced in the aqueous KGM solution exhibit great stability and dispersibility

due to specific properties of KGM. Figure 1 Schematic plot illustrating the formation and stabilization of AuNPs using konjac glucomannan. Methods Materials Chloroauric acid (HAuCl4 · 4H2O, 99.9%) was purchased from Aladdin (Shanghai, China). Purified konjac glucomannan was obtained from Shengtemeng Konjac Powder Co. (Sichuan, China). All solutions were prepared in double-distilled water, and all glassware

used was rinsed with aqua A-1155463 price regia solution (HCl/HNO3, 3:1) and then washed with double-distilled water before use. All other common reagents and solvents used in this study were of analytical grade. Synthesis of AuNPs in aqueous solution with KGM KGM powders (0.25 g) were Sclareol dispersed in double-distilled water (100 mL) by stirring for 1 h at room temperature, and then the solution was held at 80°C for 1 h. The preparation of gold nanoparticles is quite straightforward. In a typical preparation, sodium hydroxide solution (0.4 mL, 1 M) was added to KGM solution (20 mL, 0.25 wt%) under stirring, and then aqueous HAuCl4 (2 mL, 10 mM) solution was introduced. The mixture was incubated at 50°C for 3 h. The obtained gold nanoparticles were collected by centrifugation and washed thoroughly with DI water. Characterization All AP26113 molecular weight UV-visible (UV-vis) spectra were recorded on a Pgeneral TU-1810 spectrophotometer (Purkinje Inc., Beijing, China) with 1-cm quartz cells. At different time intervals, aliquots of the solution were taken out and the samples were cooled to ambient temperature and then tested immediately. The morphology of the prepared gold nanoparticles in KGM solutions was examined with a JEOL JEM-2100 F transmission electron microscope (TEM, JEOL Inc., Tokyo, Japan) operated at an acceleration voltage of 200 kV.