Our aim is to broaden the dynamic range of target DNA detection by an Au nanoparticle (AuNP) sandwich assay based on complementary DNA hybridization. We conducted electrophoresis band analysis for different sizes and concentrations of AuNPs bearing different numbers of surface-conjugated probe DNA molecules. We found that the AuNP concentration is critical to determining the maximum quantification limit (upper limit of the dynamic range). The number of immobilized probe DNAs per AuNP was also optimized to prevent errors in determining the target DNA concentration and to raise the upper limit. We examined AuNPs with diameters ranging from 15 to 40 nm at different concentrations and demonstrated tunability of the dynamic ranges spanning two to three orders of magnitude. The use of both 15 and 40 nm AuNPs can cover a dynamic range of over four orders of magnitude.

中文翻译：

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通过优化粒径，浓度和表面探针密度来调整基于金纳米颗粒的DNA杂交测定的动态范围

我们的目标是通过基于互补DNA杂交的Au纳米颗粒（AuNP）夹心测定法拓宽目标DNA检测的动态范围。我们对带有不同数量的表面结合探针DNA分子的不同大小和浓度的AuNPs进行了电泳带分析。我们发现AuNP浓度对于确定最大定量限（动态范围的上限）至关重要。还优化了每个AuNP固定的探针DNA的数量，以防止确定目标DNA浓度时出现错误并提高上限。我们检查了在不同浓度下直径范围为15至40 nm的AuNPs，并证明了跨越2至3个数量级的动态范围的可调性。