College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, PR China; Beijing Laboratory of Food Quality and Safety, Department of Nutrition and Health, China Agricultural University, Beijing 100091, PR China.
WWHS Biotech. Inc. Research Institute of Tsinghua University in Shenzhen, Shenzhen, Guangdong 518100, PR China.
J Adv Res. 2023 Aug;50:25-34. doi: 10.1016/j.jare.2022.10.008. Epub 2022 Oct 22.
Widely used in livestock breeding, residues of antibiotic drugs in milk have become a threat to food safety and human health. Current rapid detection technologies using colorimetric immunochromatographic strip tests (IST) lack the necessary sensitivity for on-site trace monitoring. Fluorescence-based detection in the near-infrared IIa' (NIR-IIa') region (1000 ∼ 1300 nm) has enormous potential due to greatly minimized auto-fluorescence and light scattering.
The aim of this work is to develop an ultrasensitive IST platform using NIR-IIa' fluorescent nanoparticles as labels for multiplex antibiotic residues detection in milk.
NIR-IIa' fluorescent nanoparticles were assembled by encapsulating synthesized NIR-IIa' fluorophores into carboxyl - modified polystyrene nanoparticles. The NIR-IIa' nanoparticles were subsequently used as labels in an IST platform to detect sulfonamides, quinolones, and lincomycin simultaneously in milk. A portable fluorescent reader was fabricated to provide on-site detection. To further validate the developed IST platform, the detection was compared with LC-MS/MS in 22 real milk samples.
Fluorescent nanoparticles were synthesized with low energy emission (1030 nm) and large Stokes shift (>250 nm) showing a much higher signal-to-noise ratio compared with fluorophores emitting in the NIR-I region. The developed IST platform yielded a highly sensitive, simultaneous quantification of sulfonamides, quinolones, and lincomycin in milk with detection limits of 46.7, 27.6 and 51.4 pg/mL, respectively, achieving a wide detection range (up to 50 ng/mL). The IST platform showed good accuracy, reproducibility, and specificity with the portable fluorescent reader which could rapidly quantify in 10 s. These results were better than reported immunochromatographic assays using fluorescent labels, and remarkably, showed a higher recognition ability than LC-MS/MS for real samples.
The utility of NIR-IIa' fluorescence-based IST platform for the fast, sensitive, and accurate detection of antibiotics in milk was demonstrated, successfully verifying the potential of this platform in detecting trace materials in complex matrices.
抗生素药物在畜牧业中的广泛应用，使得其在牛奶中的残留对食品安全和人类健康构成了威胁。目前，基于比色免疫层析条试验（IST）的快速检测技术缺乏现场痕量监测所需的灵敏度。基于近红外二区（NIR-IIa'）（1000～1300nm）的荧光检测具有巨大的潜力，因为它大大减少了自发荧光和光散射。
本工作旨在开发一种超灵敏的 IST 平台，该平台使用 NIR-IIa'荧光纳米粒子作为标记物，用于牛奶中多种抗生素残留的同时检测。
通过将合成的 NIR-IIa'荧光团包封到羧基改性聚苯乙烯纳米粒子中，组装 NIR-IIa'荧光纳米粒子。随后，将 NIR-IIa'纳米粒子用作 IST 平台中的标记物，用于同时检测牛奶中的磺胺类、喹诺酮类和林可霉素。为了提供现场检测，还制备了便携式荧光读取器。为了进一步验证所开发的 IST 平台，在 22 个实际牛奶样本中，将检测结果与 LC-MS/MS 进行了比较。
与在近红外 I 区发射的荧光团相比，合成的荧光纳米粒子具有较低的能量发射（1030nm）和较大的斯托克斯位移（>250nm），显示出更高的信噪比。所开发的 IST 平台能够高度敏感、同时定量检测牛奶中的磺胺类、喹诺酮类和林可霉素，检测限分别为 46.7、27.6 和 51.4pg/mL，检测范围（高达 50ng/mL）很宽。IST 平台与便携式荧光读取器配合使用，具有良好的准确性、重现性和特异性，可在 10s 内快速定量。这些结果优于使用荧光标记物的报道免疫层析检测，并且值得注意的是，与 LC-MS/MS 相比，对实际样品具有更高的识别能力。
本研究证明了基于 NIR-IIa'荧光的 IST 平台在牛奶中抗生素快速、灵敏和准确检测中的应用，成功验证了该平台在复杂基质中痕量物质检测中的潜力。
