GICAPC Research Group, Department of Analytical Chemistry, University of Valencia, Burjassot, Valencia, Spain.
Medical Oncology service. Biomarkers and Precision Medicine Unit (UBYMP). La Fe Hospital. La Fe Health Research Institute (IISLAFE), Valencia, Spain.
Anal Chim Acta. 2023 Aug 29;1271:341435. doi: 10.1016/j.aca.2023.341435. Epub 2023 May 30.
In this work, an analytical method for the determination of two endogenous aldehydes (hexanal and heptanal) as lung cancer biomarkers in saliva samples is presented for the first time. The method is based on a modification of magnetic headspace adsorptive microextraction (M-HS-AME) followed by gas chromatography coupled to mass spectrometry (GC-MS). For this purpose, an external magnetic field generated by a neodymium magnet is used to hold the magnetic sorbent (i.e., CoFeO magnetic nanoparticles embedded into a reversed-phase polymer) in the headspace of a microtube to extract the volatilized aldehydes. Subsequently, the analytes are desorbed in the appropriate solvent and the extract is injected into the GC-MS system for separation and determination. Under the optimized conditions, the method was validated and showed good analytical features in terms of linearity (at least up to 50 ng mL), limits of detection (0.22 and 0.26 ng mL for hexanal and heptanal, respectively), and repeatability (RSD ≤12%). This new approach was successfully applied to saliva samples from healthy volunteers and those with lung cancer, obtaining notably differences between both groups. These results reveal the prospect of the method as potential diagnostic tool for lung cancer by saliva analysis. This work contributes to the Analytical Chemistry field presenting a double novelty: on the one hand, the use of M-HS-AME in bioanalysis is unprecedentedly proposed, thus expanding the analytical potential of this technique, and, on the other hand, the determination of hexanal and heptanal is carried out in saliva samples for the first time.
本工作首次提出了一种基于修饰后的磁固相顶空吸附微萃取（M-HS-AME）联合气相色谱-质谱联用（GC-MS）分析唾液中两种内源性醛（己醛和庚醛）作为肺癌生物标志物的方法。为此，采用钕磁铁产生的外磁场将磁性吸附剂（即 CoFeO 磁性纳米粒子嵌入反相聚合物中）固定在微管的顶空部分，以萃取挥发的醛类。随后，用合适的溶剂将分析物洗脱，将提取物注入 GC-MS 系统进行分离和测定。在优化条件下，对该方法进行了验证，结果表明其具有良好的分析性能，包括线性范围（至少达到 50ng mL）、检出限（己醛和庚醛的检出限分别为 0.22 和 0.26ng mL）和重复性（RSD≤12%）。该新方法成功应用于健康志愿者和肺癌患者的唾液样本，两组间存在明显差异。这些结果表明，通过唾液分析，该方法有望成为肺癌的潜在诊断工具。本工作为分析化学领域做出了双重贡献：一方面，首次提出将 M-HS-AME 应用于生物分析，从而扩展了该技术的分析潜力；另一方面，首次在唾液样本中测定了己醛和庚醛。
