湖北农业科学
湖北農業科學
호북농업과학
2014年
9期
2143-2145
,共3页
面粉%溴酸钾%结晶紫%离子缔合物%分光光度法
麵粉%溴痠鉀%結晶紫%離子締閤物%分光光度法
면분%추산갑%결정자%리자체합물%분광광도법
wheat flour%potassium bromate%crystal violet%ion-association complex%spectrophotometric method
在硫酸介质中,BrO3-氧化I-形成I3-络阴离子,I3-络阴离子可进一步与结晶紫阳离子形成离子缔合物,在聚乙烯醇存在下,缔合物呈清亮的浅棕红色溶液,以试剂空白为参比,最大吸收波长为542 nm,吸光度与BrO3-浓度呈线性关系,线性范围为0.5~3.5μg/10 mL,表观摩尔吸光系数为1.02×105 L/(mol?cm),检出限为0.016μg/mL,样品回收率为95.2%~101.4%,RSD为2.69%。将该方法用于面粉中微量溴酸钾测定,结果令人满意。
在硫痠介質中,BrO3-氧化I-形成I3-絡陰離子,I3-絡陰離子可進一步與結晶紫暘離子形成離子締閤物,在聚乙烯醇存在下,締閤物呈清亮的淺棕紅色溶液,以試劑空白為參比,最大吸收波長為542 nm,吸光度與BrO3-濃度呈線性關繫,線性範圍為0.5~3.5μg/10 mL,錶觀摩爾吸光繫數為1.02×105 L/(mol?cm),檢齣限為0.016μg/mL,樣品迴收率為95.2%~101.4%,RSD為2.69%。將該方法用于麵粉中微量溴痠鉀測定,結果令人滿意。
재류산개질중,BrO3-양화I-형성I3-락음리자,I3-락음리자가진일보여결정자양리자형성리자체합물,재취을희순존재하,체합물정청량적천종홍색용액,이시제공백위삼비,최대흡수파장위542 nm,흡광도여BrO3-농도정선성관계,선성범위위0.5~3.5μg/10 mL,표관마이흡광계수위1.02×105 L/(mol?cm),검출한위0.016μg/mL,양품회수솔위95.2%~101.4%,RSD위2.69%。장해방법용우면분중미량추산갑측정,결과령인만의。
A highly sensitive spectrophotometry method was used to determine trace amounts of KBrO3 based on the oxidation of I- to I3- by BrO3- and the further reaction of I3- with crystal violet to form the ion-association complex in sulfuric acid medium. In the PVA, the complex was transparent brownish-red. The maximum absorption wavelength was 542 nm against reagent blank. It was found that the absolute value of the maximum absorption wavelength was proportional to the BrO3- con-centration. Beer’s law was obeyed in the rang of 0.5~3.5μg/10 mL. The apparent molar absorption coefficient was 1.02×105 L?mol-1?cm-1, with detection limit of 0.016μg/mL. The spiked recoveries were 95.2%~101.4%,with the RSD of 2.69%. The method was used to determine trace bromate in wheat flour with satisfactory results.
