In the present study, we targeted to synthesize size-dependent gold nanoparticles (Au NPs) using aqueous leaves extract of Actinodaphne madraspatna Bedd (AMB) both as reducing and stabilizing agents. The different sized Au NPs were effortlessly prepared by varying the concentration of AMB leaves extracts (2%, 3%, 4%). Characterization of synthesized Au NPs was performed by UV–Vis spectroscopy (UV–Vis), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), Brunauer–Emmett–Teller (BET) and X-ray diffraction (XRD). The synthesized Au NPs using different concentrations of AMB leaves extracts were approximately polyhedral in shape as well as the particle size of AmAu2, AmAu3, and AmAu4 nanoparticles were calculated to be 80, 60 as well as 20 nm, respectively. Small-sized particles were obtained with a higher concentration of AMB leaves extract. The potential of the prepared Au NPs as catalyst was assessed by the reduction of organic pollutant 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) using sodium borohydride (NaBH₄) as a reducing agent and AmAu4 NPs has exhibited better catalytic activity evidenced by higher rate, when compared with gold NPs reported in the literature. From the study, different sized Au NPs were found to be suitable candidates in the environmental remediation of polluted water.

在本研究中，我们的目标是使用放线猕猴桃的水生叶提取物合成尺寸依赖性的金纳米颗粒（Au NPs）（AMB）作为还原剂和稳定剂。通过改变AMB叶片提取物的浓度（2％，3％，4％），可以轻松地制备出不同大小的Au NP。紫外-可见光谱（UV-Vis），扫描电子显微镜（SEM），透射电子显微镜（TEM），傅立叶变换红外光谱（FT-IR），布鲁瑙尔-埃米特-泰勒（BET）对合成的金纳米颗粒进行了表征和X射线衍射（XRD）。使用不同浓度的AMB叶片提取物合成的Au NP形状近似多面体，AmAu2，AmAu3和AmAu4纳米粒子的粒径分别计算为80、60和20 nm。使用较高浓度的AMB叶片提取物可获得小尺寸的颗粒。₄）作为还原剂，与文献中报道的金NP相比，AmAu4 NPs表现出更好的催化活性，这由较高的速率证明。从研究中，发现不同大小的金纳米颗粒是污染环境修复的合适候选者。