Sousa Mariana P, Pereira Ana Cláudia, Correia Bárbara, do Carmo Anália, Matos Ana Miguel, Cruz Maria Teresa, Moreira Felismina T C
BioMark/CEB/LABBELS-Centre of Biological Engineering, University of Minho, 4710-057 Braga, Portugal.
Epidemiology, Outcomes, Economics and Management in Oncology Group-Portuguese Oncology Institute of Porto Research Center (CI-IPOP), Porto Comprehensive Cancer Center (Porto.CCC) & RISE@CI-IPOP (Health Research Network), 4200-072 Porto, Portugal.
Biosensors (Basel). 2025 Jun 17;15(6):390. doi: 10.3390/bios15060390.
The COVID-19 pandemic highlighted the need for rapid, cost-effective tools to monitor transmission and immune response. We developed two novel paper-based colorimetric biosensors using glutaraldehyde as a protein dye-its first use in this context. Glutaraldehyde reacts with amino groups to generate a brown color, enabling detection of SARS-CoV-2 antibodies. Wathman filter paper was functionalized with (3-aminopropyl)triethoxysilane (APTES) to immobilize virus-like particles (VLPs) and nucleocapsid protein (N-protein) as biorecognition elements. Upon incubation with antibody-containing samples, glutaraldehyde enabled colorimetric detection using RGB analysis in ImageJ software. Both sensors showed a linear correlation between antibody concentration and RGB values in buffer and serum. The VLP sensor responded linearly within the range of 1.0-20 µg/mL (green coordinate) in 500-fold diluted serum and the N-protein sensor from 1.0-40 µg/mL (blue coordinate) in 250-fold diluted serum. Both sensors demonstrated good selectivity, with glucose causing up to 18% interference. These biosensors represent a paradigm shift, as they provide a sensitive, user-friendly, and cost-effective option for semi-quantitative serological analysis. Furthermore, their versatility goes beyond the detection of SARS-CoV-2 antibodies and suggests broader applicability for various molecular targets.
新冠疫情凸显了对用于监测病毒传播和免疫反应的快速、经济高效工具的需求。我们开发了两种新型的基于纸张的比色生物传感器，使用戊二醛作为蛋白质染料——这是其在此背景下的首次应用。戊二醛与氨基反应生成棕色，从而能够检测新冠病毒抗体。用（3-氨丙基）三乙氧基硅烷（APTES）对沃特曼滤纸进行功能化处理，以固定病毒样颗粒（VLP）和核衣壳蛋白（N蛋白）作为生物识别元件。在与含抗体的样品孵育后，戊二醛通过ImageJ软件中的RGB分析实现比色检测。两种传感器在缓冲液和血清中均显示出抗体浓度与RGB值之间的线性相关性。VLP传感器在500倍稀释血清中1.0 - 20 µg/mL（绿色坐标）范围内呈线性响应，N蛋白传感器在250倍稀释血清中1.0 - 40 µg/mL（蓝色坐标）范围内呈线性响应。两种传感器均表现出良好的选择性，葡萄糖造成的干扰高达18%。这些生物传感器代表了一种范式转变，因为它们为半定量血清学分析提供了一种灵敏、用户友好且经济高效的选择。此外，它们的多功能性不仅限于检测新冠病毒抗体，还表明对各种分子靶点具有更广泛的适用性。
