利用漫反射紫外-可见反射法快速测定食品中的亚硝酸盐。
Rapid determination of nitrites in food using a diffuse UV-visible reflectance method.
机构信息
Institute of Chemistry, University of Campinas, PO Box 6154, 13083-970 Campinas, SP, Brazil.
出版信息
Food Addit Contam Part A Chem Anal Control Expo Risk Assess. 2012 Aug;29(8):1256-62. doi: 10.1080/19440049.2012.692486.
A simple, low-cost, sensitive and selective method for the determination of trace quantities of nitrite in foods such as cheese and cured meat using diffuse ultraviolet-visible reflectance was developed. It is based on the reaction of nitrite with sulphadiazine and α-naphthol, which produces a coloured product in basic medium. The reaction is carried out directly in the measuring cell. For cheese the limit of detection (LOD), expressed as NaNO₂, was estimated to be about 2.0 × 10⁻²mg l⁻¹ (2.9 × 10⁻⁷mol l⁻¹) in the final measuring solution and 0.17 mg kg⁻¹ in cheese (2.5 × 10⁻⁶mol kg⁻¹). The relative standard deviation (RSD) varied from 5% to 8% depending on the sample. For meat the LOD was estimated to be about 2.0 × 10⁻²mg l⁻¹ (2.9 × 10⁻⁷mol l⁻¹) in the final measuring solution and 0.13 mg kg⁻¹ in meat (1.9 × 10⁻⁶mol kg⁻¹). The RSD varied from 3% to 6% depending on the sample. The results of the proposed method were also compared with those obtained with the official method using the statistical Student's t-test and F-test procedures.
建立了一种简单、低成本、灵敏且选择性好的方法，可使用漫反射紫外-可见反射法测定奶酪和腌制肉类等食品中的痕量亚硝酸盐。其原理是基于亚硝酸盐与磺胺嘧啶和α-萘酚的反应，在碱性介质中生成有色产物。反应可直接在测量池中进行。对于奶酪，检测限（LOD），以 NaNO₂表示，在最终测量溶液中的估计值约为 2.0×10⁻²mg·l⁻¹（2.9×10⁻⁷mol·l⁻¹），在奶酪中的含量为 0.17 mg·kg⁻¹（2.5×10⁻⁶mol·kg⁻¹）。相对标准偏差（RSD）取决于样品，范围为 5%至 8%。对于肉类，LOD 估计在最终测量溶液中的值约为 2.0×10⁻²mg·l⁻¹（2.9×10⁻⁷mol·l⁻¹），在肉中的含量为 0.13 mg·kg⁻¹（1.9×10⁻⁶mol·kg⁻¹）。RSD 取决于样品，范围为 3%至 6%。使用统计学的学生 t 检验和 F 检验程序，将所提出方法的结果与官方方法的结果进行了比较。
Zotero 插件