The assay in serum of non-caeruloplasmin copper, as exchangeable copper after complexation with EDTA (ExCu) and total copper has been evaluated and compared in patients with varying c-reactive protein(CRP).

Measurement of ExCu and total copper, range 0.2–47.2 µmol/L, was developed using ICP-MS. The chelating agents EDTA and TEPA were compared over 0.0–10 g/L after incubation with serum for 60 mins followed by ultrafiltration with Amicon 10 kDa filter. The assay for ExCu was optimised with EDTA 3 g/L (8.1 mmol/L) maintained at pH 7.0–8.0 before ultrafiltration. TEPA was not as selective in chelation of copper. Patients n = 82 were studied in relation to changes in inflammatory marker CRP and a group of patients n = 37 with normal CRP.

The ExCu assay gave excellent recoveries (94–102 % but poor recovery for free uncomplexed copper), good repeatability, limit of quantitation 0.19 µmol/l with a provisional reference range 0.48 to 1.63 µmol/L (n = 37 patients). The range for relative exchangeable copper (exchangeable copper divided by total serum copper) was 2.49 to 9.96 %. ExCu was elevated in conditions with increased CRP greater than 100 mg/L suggesting an effect of inflammation on the free copper fraction.

A reliable and reproducible assay for ExCu and total copper has been developed. The upregulated inflammatory state increases the ExCu suggesting excess free copper.

已评估并比较了具有不同c反应蛋白（CRP）的患者的血清中非铜蓝蛋白铜的含量，作为与EDTA（ExCu）和总铜复合后的可交换铜。

使用ICP-MS开发了ExCu和总铜的测量范围为0.2-47.2 µmol / L。与血清孵育60分钟，然后用Amicon 10 kDa过滤器超滤后，将螯合剂EDTA和TEPA进行比较，浓度范围为0.0-10 g / L。在超滤之前，用保持在pH 7.0-8.0的EDTA 3 g / L（8.1 mmol / L）对ExCu的测定进行了优化。TEPA对铜螯合的选择性不高。患者Ñ  = 82进行了研究相对于在炎症标记物CRP和改变的一组患者Ñ  = 37与正常CRP。

ExCu分析的回收率极高（94-102％，但游离的未络合铜的回收率很低），重复性好，定量限为0.19 µmol / l，暂定参考范围为0.48至1.63 µmol / L（n  = 37例）。相对可交换铜（可交换铜除以总血清铜）的范围为2.49％至9.96％。在CRP增加超过100 mg / L的条件下，ExCu升高，表明炎症对游离铜部分有影响。

已经开发出一种可靠且可重复的ExCu和总铜含量测定方法。上调的炎症状态增加了ExCu，表明过量的游离铜。