Measurement of unbound bilirubin by the peroxidase test using Zone Fluidics
Measurement of unbound bilirubin by the peroxidase test using Zone Fluidics
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DOI：
10.1016/j.cca.2005.07.030
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发表时间：
2006-03-01
影响因子：
5
通讯作者：
Van Overmeire, B
中科院分区：
文献类型：
--
作者：
Ahlfors, CE;Marshall, GD;Van Overmeire, B
背景：通过过氧化物酶试验测量血浆未结合胆红素浓度对于治疗新生儿黄疸很有用。然而，市售的过氧化物酶技术是手动的，在42倍样品稀释和使用的单一过氧化物酶浓度下，未结合胆红素可能被严重低估。我们研究了通过将其调整为区域射流来改进测试，区域射流是一种用于自动化反应物处理的系统，需要小的样品体积和稀释。利用小直径油管串联水-表面活性剂储层、双向泵多端口选择阀，过氧化物酶测试反应物（45 μ l样品）连接到该多端口选择阀，其中一个端口对空气开放，以及分光光度计流动池。测试反应物和空气通过阀被顺序地吸入连接泵和阀的管道中，以形成被空气包围的反应物“区”。将该区域推进至分光光度计流动池，在流动池中，在2倍样品稀释和4种过氧化物酶浓度下，根据460 nm处的吸光度测定总胆红素和未结合胆红素（37 ℃）。在人工对照品和新生儿血浆中评估了不精密度。血浆结果进行了比较，使用商业method.Results：在各种控制的CV为未结合胆红素范围从11%至38%（天内）和12%至27%（天之间）。新生儿血浆测量值的Trifecta CV测量值范围为0.6%至31%（平均值11%，n = 47）。平均未结合胆红素由区射流是5倍高于由商业method.Conclusion：区射流可用于自动化的过氧化物酶试验，克服了许多的限制，市售的过氧化物酶技术。(c)2005 Elsevier B. V.保留所有权利。
Background: Measuring plasma unbound bilirubin concentration by the peroxidase test is useful in the management of jaundiced newborns. However, the commercially available peroxidase technology is manual, and the unbound bilirubin may be seriously underestimated at the 42-fold sample dilution and single peroxidase concentration used. We investigated improving the test by adapting it to Zone Fluidics, which is a system for automating reactant handling that requires small sample volumes and dilution.Methods: A computer-directed Zone Fluidics system was constructed using small diameter tubing to connect in series a water-surfactant reservoir, a bi-directional pump, a multiport selection valve to which peroxidase test reactants (45 mu l of sample) are attached with one port open to air, and a spectrophotometer flow cell. Test reactants and air are sequentially aspirated through the valve into the tubing connecting the pump and valve to form a reactant "zone" surrounded by air. The zone is advanced to the spectrophotometer flow cell where total and unbound bilirubin are determined (37 degrees C) from the absorbance at 460 nm at a 2-fold sample dilution and 4 peroxidase concentrations. Imprecision was assessed in artificial controls and newborn plasma. Plasma results were compared with those obtained using the commercial method.Results: The CV for unbound bilirubin in the various controls ranged from 11% to 38% (within day) and 12% to 27% (between days). Triplicate CV measurements for newborn plasma measurements ranged from 0.6% to 31% (mean 11%, n = 47). Mean unbound bilirubin by Zone Fluidics was 5-fold higher than that by the commercial method.Conclusion: Zone Fluidics can be used to automate the peroxidase test and overcome many of the limitations of the commercially available peroxidase technology. (c) 2005 Elsevier B.V. All rights reserved.