College of Veterinary Medicine, China Agricultural University, Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, Beijing Laboratory for Food Quality and Safety, Beijing, 100193, People's Republic of China.
College of Veterinary Medicine, China Agricultural University, Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, Beijing Laboratory for Food Quality and Safety, Beijing, 100193, People's Republic of China.
Anal Chim Acta. 2021 Apr 1;1152:338231. doi: 10.1016/j.aca.2021.338231. Epub 2021 Jan 22.
The donor-acceptor distance is a critical factor for the occurrence of chemiluminescent resonance energy transfer (CRET). We herein evaluate the donor-acceptor distance and transfer efficiency of CRET immunoassays of a series of donors which contain different sized antibody fragments, intact monoclonal antibody (IgG), antigen binding fragment (Fab), and single chain fragment antibody (scFv). Core/multishell quantum dots were used as the acceptor in three CRET systems. IgG is the maximum antibody fragment, leading to the longest donor-acceptor distance and the lowest transfer efficiency. Donors with Fab and scFv show significantly decreased distance and increased transfer efficiency. These results suggest an inverse correlation between donor size and transfer efficiency and can be used to provide guidance for the construction of controllable CRET. By combining the controllable CRET with immunoassay, we further develop a tunable sulfamethazine analytical system. Three different sized donors based CRET immunoassay show a markedly different sensitivity and dynamic range. Such adjustable detection provides greater flexibility for contaminant detection in different foodstuffs with different residue limits. This work not only illustrates the effect of donor-acceptor distance on regulating the energy transfer efficiency of CRET system, but also provides a guideline for the construction of a tunable immunoassay.
供体-受体距离是化学发光共振能量转移（CRET）发生的关键因素。我们在此评估了一系列供体的 CRET 免疫分析的供体-受体距离和转移效率，这些供体包含不同大小的抗体片段、完整的单克隆抗体（IgG）、抗原结合片段（Fab）和单链片段抗体（scFv）。核心/多壳量子点被用作三个 CRET 系统中的受体。IgG 是最大的抗体片段，导致最长的供体-受体距离和最低的转移效率。具有 Fab 和 scFv 的供体显示出明显减小的距离和增加的转移效率。这些结果表明供体大小与转移效率之间存在反比关系，可用于为可控 CRET 的构建提供指导。通过将可控 CRET 与免疫分析相结合，我们进一步开发了一种可调磺胺甲恶唑分析系统。基于三种不同大小供体的 CRET 免疫分析显示出明显不同的灵敏度和动态范围。这种可调检测为不同残留限量的不同食品中污染物的检测提供了更大的灵活性。这项工作不仅说明了供体-受体距离对调节 CRET 系统能量转移效率的影响，还为可调免疫分析的构建提供了指导。
