Ma Wanwan,Chen Huan,Hou Hongwei,Hu Qingyuan,Bai Yu
Phosphatidylcholine (PC) and lysophosphatidylcholine (LPC), two types of phospholipids (PLs), have been reported to be closely correlated with head and neck cancers of laryngeal cancer (LC) and thyroid cancer (TC), which make their analysis crucial. TiO 2 @COF-based solid-phase microextraction (SPME) coupled to UHPLC-MS/MS was developed for the rapid and accurate detection of seven potential PL biomarkers from small amounts of serum in this work. The combination of TiO 2 and COF proves to be effective for the extraction of the target analytes. Under optimal conditions, the developed TiO 2 @COF-based SPME-UHPLC-MS/MS method revealed good linearity ( R 2 ≥ 0.997) with LODs ranging from 0.05 to 0.38 ng/mL for PLs, the extraction recoveries and matrix effects ranging from 83.09–112.03% and 85.38–113.67%, respectively. As a high-throughput pretreatment method, satisfactory probe-to-probe reproducibility rates of 2.7–10.1% were obtained. Finally, the TiO 2 @COF-based SPME-UHPLC-MS/MS method was applied to analyze LPC 14:0, LPC 16:0, LPC 18:0, LPC 18:1, LPC 19:0, PC 16:0/18:1, and PC 18:0 in serum samples from early LC patients ( n = 15), early TC patients ( n = 15), and healthy volunteers ( n = 15). The results indicated that cancer patients could be effectively differentiated from healthy controls using orthogonal partial least squares discriminant analysis (OPLS-DA). In conclusion, the established TiO 2 @COF-based SPME-UHPLC-MS/MS method is reliable for the rapid determination of the seven PLs in serum samples, which is promising for early diagnosis of head and neck cancers. Graphical abstract
Wang Yisi,Zhang Junying,Lv Xinxin,Ding Ya,Wang Yaolong,Liu Yuanhua,Wu Chunyong,Yang Gongjun
A highly sensitive and selective label-free impedimetric immunosensor based on AuNPs@pDA@NiCo 2 S 4 @MoS 2 nanocomposite modified on the surface of a screen-printed electrode (SPE) was designed for the detection of interleukin-6 (IL-6). The distribution of NiCo 2 S 4 nanoparticles on MoS 2 nanosheets was able to prevent them from agglomerating. The polydopamine (pDA) layer was coated on the surface of NiCo 2 S 4 @MoS 2 nanosheets by self-polymerization, which improved the stability and biocompatibility of the nanomaterial. The excellent reduction ability of pDA promoted the synthesis of gold nanoparticles (AuNPs), which increased the amount of antibody adsorption and the conductivity of the material. Finally, the antibody (Ab) of IL-6 was immobilized on the surface of AuNPs@pDA@NiCo 2 S 4 @MoS 2 nanocomposite. Electrochemical impedance spectroscopy (EIS) was used to detect the change of impedance before and after the immune response between Ab and IL-6 antigen (IL-6). Under the optimal experimental conditions, the relative change in impedance and the logarithmic concentration of IL-6 showed a good linear relationship in the range 1.00 to 1.00 × 10 6 pg/mL, with a low detection limit of 0.97 pg/mL. In addition, the proposed immunosensor performed with good reproducibility, stability, and specificity. It was successfully applied to the determination of IL-6 in patient’s serum samples of head and neck carcinoma with recoveries of 98.40% to 106.5%. To sum up, the proposed label-free impedimetric immunosensor was successfully constructed for IL-6 detection in real samples. Graphical abstract