聚苯胺功能化的塑料光纤传感器用于黄曲霉毒素B1浓度检测

Plastic Optical Fiber Functionalized with Polyaniline for the Detection of Aflatoxin B1 Concentration

摘要:

为开发低成本高灵敏度黄曲霉毒素B₁(AFB₁)检测设备,研制了一种将聚苯胺(PAni)与塑料光纤(POF)相结合的增敏光纤免疫传感器。传感器功能化设计采用两步法,首先将PAni涂层修饰至光纤传感区,然后通过戊二醛的交联作用,将AFB₁抗体分子固定于传感区。由于测量过程中抗原和抗体的免疫反应会导致POF表面折射率发生变化,从而引起探测光子数的波动,以此实现对AFB₁浓度的检测。实验研究了PAni涂层对传感器的增敏效果,结果表明PAni功能化的POF传感器增敏效果明显,且在0.01~10μg/L AFB₁浓度范围内,传感器的光子数变化量与AFB₁浓度间具有线性关系,检测限为0.53μg/L,加标回收率为95.97%～113.13%,且传感器对AFB₁的特异性和抗干扰性良好,满足AFB₁精量化检测的需要。

Abstract:

To develop a low-cost and high-sensitivity device for detection of aflatoxin B₁ (AFB₁), an optical fiber immunosensor based on the functionalization of polyaniline for the detection of AFB₁ was developed. A sensitized optical fiber sensor for the detection of AFB₁ was designed by combining the excellent optical properties of polyaniline (PAni) with the soft and bending-resistant properties of the plastic optical fiber (POF). First, PAni was used to carboxylate the POF surface in the sensing region, and second, the sensing region was cross-linked with glutaraldehyde to immobilize the AFB₁ antibody molecule, which could then be obtained by the sensitized optical fiber sensor for detecting AFB₁. The sensor can detect the concentration of AFB₁ through the change in the light intensity signal of the optical fiber output caused by the immune response. The sensitizing effect of the polyaniline coating on the sensor was experimentally investigated, and the specificity, immunity to interference, and detection limit of the sensor were tested. The results showed that there was a linear relationship between the output signal of the sensor and the AFB₁ concentration in the range of 0.01~10μg/L, and the detection limit was 0.53μg/L. The recoveries of the spiked standard ranged from 95.97% to 113.13%, and the specificity and immunity of the sensor were good, thus meeting the needs of a refined detection of AFB₁.