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用鲱鱼精DNA(hsDNA)修饰10 nm的纳米金制备了Hg~(2+)的hsDNA修饰纳米金共振散射光谱探针(AuhsDNA).在pH 7.0 Tris-HCI缓冲溶液中及0.017 mol/L NaCl存在下,Hg~(2+)与AuhsDNA形成稳定的Hg~(2+)-DNA结合物,引起AuhsDNA中的纳米金析出并聚集形成纳米金簇.该溶液用150 nm滤膜过滤后.滤液中过量的AuhsDNA可催化Fehling试剂-葡萄糖反应生成氧化亚铜微粒,该微粒在580 nm处有一个较强的共振散射峰.随着汞离子浓度增大,形成的纳米金簇越多,滤液中AuhsDNA越少,生成的氧化亚铜微粒减少,580 nm处氧化亚铜微粒的共振散射光强度线性降低,其共振散射光强度降低值△I_(580nm)与汞离子浓度在1～833 nmol/L范围内成线性,回归方程、相关系数、检出限分别为△I_(580mn)=0.37C_(Gg~(2+))+0.9,0.9990,0.3 nmol/L Hg~(2+).该法用于废水中Hg~(2+)的检测.“,”Herring sperm DNA (hsDNA) was used to modify 10 nm nanogold to obtain a resonance scat-tering (RS) spectral probe (AuhsDNA) for Hg~(2+). In the medium of pH 7.0 Tris-HCl-0.017 mol/L NaCl, Hg~(2+) interacted with AuhsDNA to form stable Hg~(2+)-hsDNA complex and larger nanogold clusters, which could be removed by membrane filtration. The excess AuhsDNA in the filtration solution exhibited catalytic effect on the Fehling reagent-glucose reaction to form Cu_2O particles that exhibit the strongest RS peak at 580 nm. With addition of Hg~(2+), the excess AuhsDNA in the filtration solution decreased accordingly, and the RS intensity at 580 nm decreased. The decreased RS intensity (△I_(580nm)) was linear to Hg~(2+)concentration in the range of 1 ～833 nmol/L, with regression equation of △I_(580 nm)= 0.37C_(Hg~(2+))+0.9, coefficient of 0.9990 and detection limit of 0.3 nmol/L. The proposed method was applied to detect Hg~(2+) in water samples with satisfactory results.