Biochemistry and Molecular Biology Department, Universidade Federal de Viçosa, Av. P. H. Rolfs, s/n, Campus Universitário, CEP, 36570-000, Viçosa, MG, Brazil.
General Biology Department, Universidade Federal de Viçosa, Av. P. H. Rolfs, s/n, Campus Universitário, CEP, 36570-000, Viçosa, MG, Brazil.
Anal Biochem. 2022 Jun 1;646:114648. doi: 10.1016/j.ab.2022.114648. Epub 2022 Mar 9.
Lateral flow immunochromatography is a widely used technique for immunological assays. Construction of test and control lines is mostly done by antigen adsorption to nitrocellulose membranes, a process not fully understood. This study aimed to evaluate the influence of urea, salts, and Tween 20, on adsorption. The performance of canine IgG in water and in buffer containing urea and salts (pH 8.3) were compared to observe if the interferents would lead to protein stripping when challenged with increasing concentrations of Tween 20 in the lateral flow buffer. Immobilization of the rLiNTPDase2, an antigen for Canine Leishmaniasis diagnosis, was evaluated and compared to the rLbNTPDase2 by the same method. There were no differences between adsorption coefficients of IgG in water and in buffer, but high salt and urea concentrations seems to stabilize and enhance IgG immobilization. Adsorption performance between canine IgG and rNTPDases had different patterns, but was highly similar between rNTPDases, indicating that protein identity may have an important role. Also, low concentrations of Tween 20 in the flow solution may aid the maintenance of rNTPDase2 on the strips. Our results bring insights about protein adsorption and perspectives about the influence of urea, salts and Tween 20 on this process.
侧向流动免疫层析是一种广泛用于免疫分析的技术。测试线和控制线的构建大多通过抗原吸附到硝酸纤维素膜上完成，但这一过程尚未被完全理解。本研究旨在评估尿素、盐和吐温 20 对吸附的影响。比较了犬 IgG 在水中和含有尿素和盐（pH 8.3）的缓冲液中的性能，以观察当侧向流动缓冲液中吐温 20 的浓度增加时，这些干扰物是否会导致蛋白质洗脱。还评估了 rLiNTPDase2（犬利什曼病诊断的一种抗原）的固定化，并通过相同的方法与 rLbNTPDase2 进行了比较。在水中和缓冲液中，IgG 的吸附系数没有差异，但高盐和尿素浓度似乎稳定并增强了 IgG 的固定化。犬 IgG 和 rNTPDases 之间的吸附性能模式不同，但 rNTPDases 之间非常相似，表明蛋白质的同一性可能起重要作用。此外，流动溶液中低浓度的吐温 20 可能有助于 rNTPDase2 在条带上的维持。我们的结果提供了关于蛋白质吸附的见解，并探讨了尿素、盐和吐温 20 对这一过程的影响。
