分光光度法测定菠菜中亚硝酸盐含量的方法研究

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中图分类号：TS207 文献标志码：A 文章编号：1674-0270（2025）32-0102-03

Study on Determination of Nitrite Content in Spinach by Spectrophotometry

HUANG Simin，LUO Danru， CHEN Tingting （Guangdong Huizhou Quality Metrology Supervision and Inspection Institute，Huizhou 516ooo， China）

Abstract：This paper aims to clarify a spectrophotometric method for determining nitrite content in spinach. Commercial spinach samples were homogenized，extracted with hot borax solution，and purified using potassium ferricyanideandzincacetate.Nitritewasconverted intoapurple-redazodyethroughadiazotization-coupling reaction withsulfanilicacidandN-（1-naphthyl）ethylenediamine，andtheabsorbance was measuredatthewavelengthof 540 nm. Quantification wasperformedusing theexternalstandardmethod，andmethodvalidationincluded evaluationsoflinearity precision，accuracy，andsensitivity.Theresultsshowsthatnitriteshowsgoodlinearity withintherangeofO～0.240 μz .Six parallel measurements of the same sample yield an SRSD of 1.92% ，indicating good repeatability. The spiked recoveries range from 98.0% to 100.4% ，meeting the accuracy requirements.Based on11 blank measurements，the method detection limit and quantificationlimitarecalculatedtobeO.OO27mg/kgandO.o09Omg/kg，respectively.Thenitritecontentinthespinach sample is 0.0145mg/kg ，which is below the national maximum limit.The spectrophotometric method is simple to operate，sensitive，and accurate，making it suitable for routine determination of nitrite content in spinach.

Key Words：spinach; nitrite; spectrophotometry

菠菜生长周期短、吸收能力强，易受土壤条件、施肥方式、采收时间及储运环境等因素影响而积累一定的亚硝酸盐。（剩余3408字）