Exosome concentration and exosomal proteins are regarded as promising cancer biomarkers. Herein, a waxberry-like magnetic bead (magnetic-nanowaxberry) which has huge surface area and strong affinity was synthesized to couple with aptamer for exosome capture and recovery. Subsequently, we developed a fluorescent assay for the sensitive, accurate, and simultaneous quantification of exosome and cancer-related exosomal proteins [epidermal growth factor receptor (EGFR) and epithelial cell adhesion molecule (EpCAM)] by using triple-colored probes to recognize EGFR and EpCAM or spontaneously anchor to the lipid bilayer. In this design, the interference of soluble proteins can be avoided due to the dual recognition strategy. Moreover, the lipidbased quantification of exosome concentration can improve the accuracy. Besides, the simultaneous detection mode can save samples and simplify the operation steps. Consequently, the assay shows high sensitivity (the limits of detection are down to 0.96 pg/mL for EGFR, 0.19 pg/mL for EpCAM, and 2.4 × 10 4 particles/ μL for exosome), high specificity, and satisfactory accuracy. More importantly, this technique is successfully used to analyze exosomes in plasma to distinguish cancer patients from healthy individuals. To improve the diagnostic efficacy, the deep learning was used to exploit the potential pattern hidden in data obtained by the proposed method. Also, the accuracy for the intelligent diagnosis of cancer can achieve 96.0%. This study provides a new avenue for developing new biosensors for exosome analysis and intelligent disease diagnosis.

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We herein describe a high-throughput 96-well plate micro-solid phase extraction sample preparation technique based on novel sulfonated-polyaniline/polyacrylonitrile nanofiber mats (sulfonated-PANI/PAN NFMs) for multiresidue detection of fluoroquinolones (FQs) in various animal-origin food samples. Through the double-modification of polyaniline and sulfonic acid, the resulting functionalized sulfonated-PANI/PAN NFMs present high extraction efficiency for FQs. Compared with the existing methods, this approach demonstrates its advantages of being suitable for more sample matrices (milk, animal muscle, liver, kidney, and egg), lower sample amount (0.5 g), lower sorbent requirement (5.0 mg), lower volume of organic solvent (0.7 mL), shorter time (0.2 min per sample), and high sensitivity (0.012−0.06 μg•kg −1 ). In addition, sulfonated-PANI/ PAN NFMs possess excellent reusability which could be reused 10 times without an obvious decrease in extraction efficiency. Combined with ultra performance liquid chromatography-tandem mass spectrometry, the novel sample preparation technique can be expected as an efficient method for routine trace FQ residue monitoring in animal-origin food samples.

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We have developed and validated a simple, eco‐friendly, and reliable method to simultaneously determine paracetamol and chloramphenicol in meat with ultra performance liquid chromatography and tandem mass spectrometry. The samples were firstly extracted with ethylenediaminetetraacetic acid–McIlvaine's buffer and then purified by solid‐phase extraction by using a novel core‐shell polyaniline/polyacrylonitrile nanofibers mat. Compared with existing methods for the two analytes, the proposed method was simplified greatly with much fewer sample preparation steps, consumed much less time (< 2 min per sample) and organic solvent (0.7 mL per sample). Low detection levels (0.15–0.20 µg/kg for paracetamol, 0.01 µg/kg for chloramphenicol) with good precision and recoveries of the target compounds were obtained. The proposed method was applied to determine the residual paracetamol and chloramphenicol in pork, chicken, and beef samples, and the test results were consistent with those using the Chinese national standard methods, which demonstrates the reliability and practicality of the new method.