APIX Analytics, Miniparc Polytec, Immeuble Tramontane, 60 rue des Berges, 38000 Grenoble, France.
Total S.A., Centre Scientifique et Technique Jean Féger (CSTJF), Avenue Larribau, 64000 Pau, France.
Anal Chem. 2020 Dec 15;92(24):15845-15853. doi: 10.1021/acs.analchem.0c03157. Epub 2020 Nov 24.
A nano-gravimetric detector (NGD) for gas chromatography is based on a nanoelectromechanical array of adsorbent-coated resonating double clamped beams. NGD is a concentration-sensitive detector and its sensitivity is analyte-dependent based on the affinity of the analyte with the porous layer coated on the NEMS surface. This affinity is also strongly related to the NGD temperature (NGD working temperature can be dynamically set up from 40 to 220 °C), so the sensitivity can be tuned through temperature detector control. An adsorption-desorption model was set up to characterize the NGD response on a large set of -alkanes from C to C at different NGD temperatures. For fast identification of petroleum mixture based on chromatogram fingerprint, a general strategy for NGD temperature program design was developed leading to a constant relative response factor between 0.96 and 1.03 for all the alkanes, and then chromatograms are very similar to those obtained with a flame ionization detector (FID). The analysis of a real petroleum fluid was also performed and compared to FID results: quantitative results obtained for all the analytes were satisfactory according to precision (<5%) and accuracy (average relative error = 4.3%). Based on such temperature control strategy, NGD sensitivity and the dynamic linear range can be adjusted and detection limits at a picogram level can be easily achieved for all -alkanes.
一种用于气相色谱的纳米重力探测器（NGD）基于吸附剂涂覆的共振双夹持梁的纳米机电阵列。NGD 是一种浓度敏感的检测器，其灵敏度取决于分析物与涂覆在 NEMS 表面的多孔层之间的亲和力，而亲和力又与 NGD 温度密切相关（NGD 工作温度可从 40 到 220°C 动态设定），因此可以通过温度探测器控制来调节灵敏度。建立了一个吸附-解吸模型，以表征在不同 NGD 温度下对从 C 到 C 的一系列 -烷烃的 NGD 响应。为了基于色谱指纹快速识别石油混合物，开发了一种用于 NGD 温度程序设计的通用策略，导致所有烷烃之间的相对响应因子在 0.96 到 1.03 之间保持恒定，然后得到的色谱图与使用火焰电离检测器（FID）获得的色谱图非常相似。还对实际石油流体进行了分析并与 FID 结果进行了比较：根据精密度（<5%）和准确度（平均相对误差=4.3%），所有分析物的定量结果都令人满意。基于这种温度控制策略，可以调节 NGD 的灵敏度和动态线性范围，并可轻松实现所有 -烷烃的皮克级检测限。
