Chiem N, Harrison D J
Department of Chemistry, University of Alberta, Edmonton, Canada.
Anal Chem. 1997 Feb 1;69(3):373-8. doi: 10.1021/ac9606620.
A microchip capillary electrophoresis device has been used to separate the reaction products of homogeneous, immunological reactions within approximately 40 s. Determination of monoclonal mouse IgG in mouse ascites fluid, via a direct assay, and the drug theophylline in serum samples, via a competitive assay, was demonstrated on-chip. The mouse anti-bovine serum albumin IgG assay gave a linear calibration curve up to at least 135 micrograms/mL, with +/- 3% precision. The theophylline assay gave a threshold for detection of 1.25 ng/mL in diluted serum. A calibration curve of signal vs undiluted log[theophylline] is linear from 2.5 to 40 micrograms/mL, which includes the therapeutically useful range. Theophylline recoveries in spiked samples were 100%, within an experimental error of +/- 5%. A buffer system consisting of 0.05 M tricine adjusted to pH 8.0, 0.01% (w/v) Tween 20, and approximately 40 mM NaCl was used. This buffer allowed for adequate separation (40,000 plates for theophylline; 1000 plates for theophylline-antibody complex and for human IgG) and gave reproducibility of migration times of 1-1.5% over 4-day periods, indicating minimal problems from adsorption in the uncoated chips.
一种微芯片毛细管电泳装置已被用于在约40秒内分离均相免疫反应的产物。在芯片上展示了通过直接测定法测定小鼠腹水中的单克隆小鼠IgG，以及通过竞争测定法测定血清样品中的药物茶碱。小鼠抗牛血清白蛋白IgG测定法给出了至少135微克/毫升的线性校准曲线，精密度为±3%。茶碱测定法在稀释血清中的检测阈值为1.25纳克/毫升。信号与未稀释的对数[茶碱]的校准曲线在2.5至40微克/毫升范围内呈线性，其中包括治疗有效范围。加标样品中茶碱的回收率为100%，实验误差为±5%。使用了一种缓冲系统，该系统由调节至pH 8.0的0.05 M三（羟甲基）甲基甘氨酸、0.01%（w/v）吐温20和约40 mM氯化钠组成。这种缓冲液能够实现充分分离（茶碱的理论塔板数为40,000；茶碱-抗体复合物和人IgG的理论塔板数为1000），并且在4天内迁移时间的重现性为1-1.5%，表明未涂层芯片中的吸附问题最小。
