A novel ferricyanide/Prussian blue (PB) assay for total antioxidant capacity (TAC) determination was developed exploiting the formation of PB nanoparticles in the presence of polyvinylpyrrolidone (PVP) as stabilizer. This improved method, named as “nanoparticle-based ferricyanide/Prussian blue assay (PBNP)”, was applied to the TAC measurement of Cynara Scolymus L. (globe artichoke). The calibration results of the novel (PBNP) method were compared with those of a similar nanoparticle PB method performed in the absence of PVP, and of a sodium dodecyl sulfate-modified and acid-optimized ferricyanide reference assay. Compared to similar common Fe(III)-based TAC assays, much higher molar absorptivities, pointing out higher response to different kinds of antioxidants, were obtained with PBNP for all tested antioxidants, and lower LOD and LOQ values were achieved for thiols. As an additional advantage, methionine, not responding to other electron-transfer based TAC reagents, could be measured. PBNP could detect various antioxidants with one-two orders-of-magnitude lower LOD values than those of widely used TAC assays like CUPRAC and Folin-Ciocalteau well correlating with the proposed assay.

通过在聚乙烯吡咯烷酮（PVP）作为稳定剂存在下形成PB纳米颗粒，开发了一种用于测定总抗氧化剂能力（TAC）的新颖铁氰化物/普鲁士蓝（PB）测定法。将该改进的方法称为“基于纳米颗粒的铁氰化物/普鲁士蓝测定法（PBNP）”，该方法被用于Tyn球菌的TAC测量L.（朝鲜蓟）。将新型（PBNP）方法的校准结果与在没有PVP的情况下进行的相似纳米颗粒PB方法的校准结果以及十二烷基硫酸钠修饰和酸优化的铁氰化物参比分析的校准结果进行了比较。与类似的基于Fe（III）的常见TAC分析相比，PBNP对所有测试的抗氧化剂均具有更高的摩尔吸收率，表明对不同类型的抗氧化剂的响应更高，而硫醇的LOD和LOQ值较低。作为另一个优点，可以测量不响应其他基于电子转移的TAC试剂的蛋氨酸。PBNP可以检测到各种抗氧化剂，其LOD值比广泛使用的TAC分析（如CUPRAC和Folin-Ciocalteau）的LOD值低1-2个数量级，与建议的分析具有很好的相关性。