ABTS diammonium salt (AzBTS-(NH4)2) is a substrate for horseradish peroxidase (HRP), commonly used for developing micro-technique of enzyme-linked immunosorbent assay (ELISA)[1]. ABTS is sensitive and stable in visuality by the bluish-green color for HRP[1]. The ABTS serves as the foundation for an enhanced TEAC (Trolox Equivalent Antioxidant Capacity) method to measure the antioxidant capabilities of specific radical scavengers, including copper proteins (i.e. hemocyanin, ceruloplasmin or diamine oxidase) and some copper complexes (i.e. serine2–copper)[2]. The ABTS diammonium salt-based assay is widely employed to determine the antioxidant capacity of solid samples, including active packaging materials and conducting polymers[3].
ABTS diammonium salt-based assay coupled with high-performance liquid chromatography-diode array-mass spectrometry (HPLC-DAD-MS) equipment was employed for identification and quantification of free radical scavengers in different samples of Pu-erh tea[4]. ABTS is usually used as a substrate and is prepared in McIlvaine-puffer buffer (pH 2.2-7.5), 50mmol/L sodium acetate buffer (pH 3.0-6.0), and 100mmol/L sodium tartrate buffer (pH 2.0-5.5) to determine the optimal pH of purified rPsaDyP[5].
References:
[1] Matsuda H, Tanaka H, Blas B L, et al. Evaluation of ELISA with ABTS, 2-2'-azino-di-(3-ethylbenzthiazoline sulfonic acid), as the substrate of peroxidase and its application to the diagnosis of schistosomiasis[J]. The Japanese Journal of Experimental Medicine, 1984, 54(3): 131-138.
[2] Konan K V, Le Tien C, Mateescu M A. Electrolysis-induced fast activation of the ABTS reagent for an antioxidant capacity assay[J]. Analytical Methods, 2016, 8(28): 5638-5644.
[3] Hsu C F, Peng H, Basle C, et al. ABTS•+ scavenging activity of polypyrrole, polyaniline and poly (3, 4‐ethylenedioxythiophene)[J]. Polymer international, 2011, 60(1): 69-77.
[4] Qian Z M, Guan J, Yang F Q, et al. Identification and quantification of free radical scavengers in Pu-erh tea by HPLC-DAD-MS coupled online with 2, 2′-azinobis (3-ethylbenzthiazolinesulfonic acid) diammonium salt assay[J]. Journal of Agricultural and Food Chemistry, 2008, 56(23): 11187-11191.
[5] Lauber C, Schwarz T, Nguyen Q K, et al. Identification, heterologous expression and characterization of a dye-decolorizing peroxidase of Pleurotus sapidus[J]. AMB express, 2017, 7: 1-15.
ABTS diammonium salt (AzBTS-(NH4)2)是辣根过氧化物酶（HRP）的底物，常用于酶联免疫吸附测定（ELISA）微量技术的开发[1]。ABTS因蓝绿色特性对HRP具有高灵敏度和稳定性[1]。ABTS是改进型TEAC（Trolox等效抗氧化能力）法的核心试剂，用于测定特定自由基清除剂（如铜蛋白类：血蓝蛋白、铜蓝蛋白或二胺氧化酶）及某些铜络合物（如丝氨酸2-铜复合物）的抗氧化能力[2]。基于ABTS diammonium salt的检测法被广泛用于测定固体样品（包括活性包装材料和导电聚合物）的抗氧化活性[3]。
基于ABTS diammonium salt的检测方法结合高效液相色谱-二极管阵列-质谱联用技术（HPLC-DAD-MS），被用于鉴定和定量不同普洱茶样品中的自由基清除剂[4]。ABTS通常作为底物，可配制于以下缓冲体系中以测定纯化rPsaDyP酶的最适pH：McIlvaine缓冲液（pH 2.2-7.5）、50mmol/L乙酸钠缓冲液（pH 3.0-6.0）或100mmol/L酒石酸钠缓冲液（pH 2.0-5.5）[5]。