Lateral flow immunoassay (LFIA) is a widely used express method and offers advantages such as a short analysis time, simplicity of testing and result evaluation. However, an LFIA based on gold nanospheres lacks the desired sensitivity, thereby limiting its wide applications. In this study, spherical nanogold labels along with new types of nanogold labels such as gold nanopopcorns and nanostars were prepared, characterized, and applied for LFIA of model protein antigen procalcitonin. It was found that the label with a structure close to spherical provided more uniform distribution of specific antibodies on its surface, indicative of its suitability for this type of analysis. LFIA using gold nanopopcorns as a label allowed procalcitonin detection over a linear range of 0.5–10 ng mL⁻¹ with the limit of detection of 0.1 ng mL⁻¹, which was fivefold higher than the sensitivity of the assay with gold nanospheres. Another approach to improve the sensitivity of the assay included the silver enhancement method, which was used to compare the amplification of LFIA for procalcitonin detection. The sensitivity of procalcitonin determination by this method was 10 times better the sensitivity of the conventional LFIA with gold nanosphere as a label. The proposed approach of LFIA based on gold nanopopcorns improved the detection sensitivity without additional steps and prevented the increased consumption of specific reagents (antibodies).

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横向流动免疫测定法（LFIA）是一种广泛使用的表达方法，具有分析时间短，测试和结果评估简便等优点。然而，基于金纳米球的LFIA缺乏所需的灵敏度，从而限制了其广泛的应用。在这项研究中，球形纳米金标记以及新型的纳米金标记如金纳米爆米花和纳米星被制备，表征，并用于模型蛋白抗原降钙素的LFIA。发现具有接近球形结构的标记在其表面上提供了特异性抗体更均匀的分布，表明其适用于这种类型的分析。LFIA以金纳米爆米花为标记，可在0.5–10 ng mL ^-1的线性范围内检测降钙素检出限为0.1 ng mL ^-1，比金纳米球测定的灵敏度高五倍。另一种提高测定灵敏度的方法包括银增强法，该方法用于比较用于降钙素原检测的LFIA的扩增。用该方法测定降钙素原的灵敏度是使用金纳米球作为标记的传统LFIA的灵敏度的10倍。基于金纳米爆米花的LFIA的拟议方法无需其他步骤即可提高检测灵敏度，并避免了特定试剂（抗体）的消耗量增加。

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