目前,测定微量氰化物应用最为普遍的方法仍是比色或分光光度法,因其简便易行,灵敏度较高。但现行比色或分光光度测氰法大多都要使用恶臭、毒性大的试剂,或者试剂配制较繁,受温度和时间影响较大。本文介绍一种分光光度测氰法——异菸酸巴比妥酸法,所用试剂无臭无毒,灵敏度高,氰检测下限可达4ppb。同时试剂配制简易又较稳定, At present, the most commonly used method for the determination of trace cyanide is colorimetry or spectrophotometry, because of its simplicity and sensitivity. However, the current colorimetric or spectrophotometric cyanide methods mostly use malodour, toxic reagents, or reagent preparation more complex, affected by the temperature and time. This article describes a spectrophotometric method cyanide - isonicotinic acid barbituric acid method, the reagent odorless non-toxic, high sensitivity, cyanide detection limit of up to 4ppb. At the same time reagent preparation simple and more stable,