Development of sensitive, facile and rapid biosensors is important for widespread applications. Nanozymes can be ideal signal donors for constructing dual-readout lateral flow immunoassays (LFIA) because they are an excellent class of optical reporters. Herein, a magnetic prussian blue nanozyme (MPBN) mediated dual-readout on-demand multiplex lateral flow immunoassay (MLFIA) was established by employing ractopamine (RAC) and clenbuterol (CLE) as the model analytes. The MPBN was synthesized through in-suit shell-growing and introduced as a bifunctional signal tag owing to their darker original color and peroxidase-like activity. Based on the catalytic signal created by catalyzing oxidation of chromogenic substrate 3,3′,5,5′-tetramethylbenzidine (TMB) and colorimetric signal generated by tag's original color, improved precision and broadened detection range were acquired by implementing a dual-readout strategy. And a two-fold increase in the detection range could fulfill different limit requirements of the same target in various regions. The obtained recoveries from 84.01% to 119.94% indicating the repeatability and reliability of the proposed method. This method provides an attractive platform for the detection of a same target with different detection limits, which possesses a considerable potential in monitoring of other targets.

灵敏，轻便和快速的生物传感器的开发对于广泛的应用很重要。纳米酶可以是构建双读数侧向流免疫测定（LFIA）的理想信号供体，因为它们是一类优秀的光学报告基因。本文中，以莱克多巴胺（RAC）和克仑特罗（CLE）作为模型分析物，建立了磁性普鲁士蓝纳米酶（MPBN）介导的双读数点播多重侧流免疫分析（MLFIA）。MPBN是通过套装内壳生长合成的，并由于其较暗的原始颜色和过氧化物酶样活性而作为双功能信号标签引入。根据催化发色底物3,3'，5,5'-四甲基联苯胺（TMB）氧化产生的催化信号和标签原始颜色产生的比色信号，通过实施双重读出策略，提高了精度并扩大了检测范围。检测范围的两倍扩大可以满足不同区域对同一目标的不同限制要求。获得的回收率从84.01％到119.94％，表明了所提出方法的可重复性和可靠性。该方法为具有不同检测限的同一目标的检测提供了一个有吸引力的平台，在监视其他目标方面具有相当大的潜力。