Centro de Química Estrutural, Institute of Molecular Sciences, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal.
Molecules. 2023 Jan 25;28(3):1179. doi: 10.3390/molecules28031179.
In this work, a new analytical approach is proposed for monitoring biogenic volatile organic compounds (BVOCs) by combining headspace bar adsorptive microextraction (HS-BAμE) with gas chromatography-mass spectrometry (GC-MS). The HS-BAμE methodology was developed, optimized, validated and applied for the analysis of BVOCs emitted from two tree species ( Labill. and Aiton) and compared with headspace solid phase microextraction (HS-SPME), commonly accepted as a reference technique. To achieve optimum experimental conditions, numerous assays were carried out by both methodologies, studying the release of the five major monoterpenoids (α-pinene, β-pinene, myrcene, limonene and 1,8-cineole) from the leaves of the tree species, whereas the maximum selectivity and efficiency were obtained using an activated carbon and PDMS/DVB fiber as sorbent phases for HS-BAμE and HS-SPME, respectively. Under optimized experimental conditions, both methodologies showed similar profiling and proportional responses, although the latter present a higher sensitivity in the analytical configuration used. For the five monoterpenoids studied, acceptable detection limits (LODs = 5.0 μg L) and suitable linear dynamic ranges (20.0-100.0 mg L; ≥ 0.9959) were achieved, and intra- and inter-day studies proved that both methodologies exhibited good results (RSD and %RE ≤ 19.9%), which indicates a good fit for the assessment of BVOCs by the HS-BAμE/GC-MS methodology. Assays performed on sampled leaves by both optimized and validated methodologies showed high levels of the five major BVOCs released from Labill. (10.2 ± 1.3 to 7828.0 ± 40.0 μg g) and Aiton (9.2 ± 1.4 to 3503.8 ± 396.3 μg g), which might act as potential fuel during forest fire's propagation, particularly under extreme atmospheric conditions. This is the first time that BAμE technology was applied in the HS sampling mode, and, in addition to other advantages, it has proven to be an effective and promising analytical alternative for monitoring VOCs, given its great simplicity, easy handling and low cost.
在这项工作中，提出了一种新的分析方法，通过将顶空吸附微萃取（HS-BAμE）与气相色谱-质谱（GC-MS）相结合来监测生物挥发性有机化合物（BVOCs）。开发、优化、验证了 HS-BAμE 方法，并将其应用于两种树种（ Labill. 和 Aiton）排放的 BVOCs 分析，并与顶空固相微萃取（HS-SPME）进行了比较，后者通常被认为是一种参考技术。为了达到最佳的实验条件，通过两种方法进行了大量的测定，研究了这两种树种叶片中五种主要单萜烯（α-蒎烯、β-蒎烯、月桂烯、柠檬烯和 1,8-桉叶油醇）的释放情况，而采用活性炭和 PDMS/DVB 纤维作为吸附相时，HS-BAμE 和 HS-SPME 分别获得了最大的选择性和效率。在优化的实验条件下，两种方法都表现出相似的分析谱图和比例响应，尽管后者在使用的分析配置中具有更高的灵敏度。对于所研究的五种单萜烯，达到了可接受的检测限（LOD=5.0μg/L）和合适的线性动态范围（20.0-100.0mg/L；≥0.9959），并且日内和日间研究表明，两种方法都取得了良好的结果（RSD 和 %RE≤19.9%），这表明 HS-BAμE/GC-MS 方法非常适合评估 BVOCs。通过两种优化和验证的方法对采样叶片进行的测定表明，从 Labill.（10.2±1.3 到 7828.0±40.0μg/g）和 Aiton（9.2±1.4 到 3503.8±396.3μg/g）释放的五种主要 BVOCs 水平较高，这可能在森林火灾传播过程中充当潜在的燃料，特别是在极端大气条件下。这是首次将 BAμE 技术应用于 HS 采样模式，此外，除了其他优点外，由于其简单易用、成本低，该技术还被证明是一种有效的、有前途的监测 VOCs 的分析替代方法。
