The use of colorimetric bioassays for protein detection is one of the most promising diagnostic approaches, but their relatively poor detection limits have been a critical issue. In this study, we developed an efficient colorimetric bioassay based on antibody-coated peroxidase-mimicking Au nanoparticles (Au NPs) for the detection of prostate-specific antigen (PSA), which is one of the most widely used protein biomarkers for the diagnosis of prostate and breast cancers. Anti-PSA antibody adsorption on the Au NP surface result in 65% of the peroxidasemimicking properties of Au NPs was suppressed to maximize sensitivity of the assay. Anti-PSA antibody adsorption on the Au NP was optimized at 150 µg/mL anti-PSA4 antibody for 1 h incubation, and their surface was blocked with 2% BSA. The experimental conditions of the immunoassay detection were also investigated. A highest assay value was obtained at 10 µg/mL anti-PSA1 capture antibody using 3% BSA for surface blocking and at 2.5 pM anti- PSA4-Ab coated Au NPs for 1 h incubation with PSA antigen. As a result, PSA was detected at a wide range of 0.25 to 2,500 ng/mL with a detection limit of 0.23 ng/mL. The anti-PSA-Ab coated Au NP- based assay was simple, easy to operate, and sensitive. The proposed peroxidase-mimicking anti-PSA Ab-coated Au NP-based assay could be further developed to detect other protein biomarkers.

中文翻译：

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使用过氧化物酶模拟抗PSA抗体包被的金纳米颗粒的比色灵敏检测前列腺特异性抗原

比色生物测定法用于蛋白质检测是最有前途的诊断方法之一，但是它们相对较差的检测限是一个关键问题。在这项研究中，我们开发了一种基于抗体包被的过氧化物酶模拟Au纳米颗粒（Au NPs）的高效比色生物测定法，用于检测前列腺特异性抗原（PSA），这是最广泛使用的蛋白质生物标记物之一，可用于诊断前列腺癌。前列腺癌和乳腺癌。抗PSA抗体在Au NP表面的吸附导致抑制了Au NPs过氧化物酶模拟特性的65％，从而最大程度地提高了测定的灵敏度。在150 µg / mL的抗PSA4抗体中孵育1 h可以优化抗NPA抗体在Au NP上的吸附，并用2％BSA封闭其表面。还研究了免疫检测的实验条件。在使用10％g / mL抗PSA1捕获抗体，使用3％BSA进行表面封闭和在2.5 pM抗PSA4-Ab包被的Au NP进行PSA抗原孵育1小时时，获得了最高的测定值。结果，在0.25至2500 ng / mL的宽范围内检测到PSA，检测极限为0.23 ng / mL。抗PSA-Ab包被的Au NP基检测方法简单，易于操作且灵敏度高。拟议的模仿过氧化物酶的抗PSA Ab包被的Au NP基检测方法可以进一步开发，以检测其他蛋白质生物标志物。500 ng / mL，检出限为0.23 ng / mL。抗PSA-Ab包被的Au NP基检测方法简单，易于操作且灵敏度高。拟议的模仿过氧化物酶的抗PSA Ab包被的Au NP基检测方法可以进一步开发，以检测其他蛋白质生物标志物。500 ng / mL，检出限为0.23 ng / mL。抗PSA-Ab包被的Au NP基检测方法简单，易于操作且灵敏度高。拟议的模仿过氧化物酶的抗PSA Ab包被的Au NP基检测方法可以进一步开发，以检测其他蛋白质生物标志物。