School of Chemistry, The University of Melbourne, Parkville, VIC 3010, Australia.
Anal Chim Acta. 2013 Jul 5;786:70-7. doi: 10.1016/j.aca.2013.05.021. Epub 2013 May 19.
The consumption of ethanol is known to increase the likelihood of oral cancer. In addition, there has been a growing concern about possible association between long term use of ethanol-containing mouthwashes and oral cancer. Acetaldehyde, known to be a carcinogen, is the first metabolite of ethanol and it can be produced in the oral cavity after consumption or exposure to ethanol. This paper reports on the development of a gas-diffusion flow injection method for the online determination of salivary acetaldehyde by its colour reaction with 3-methyl-2-benzothiazolinone hydrazone (MBTH) and ferric chloride. Acetaldehyde samples and standards (80 μL) were injected into the donor stream containing NaCl from which acetaldehyde diffused through the hydrophobic Teflon membrane of the gas-diffusion cell into the acceptor stream containing the two reagents mentioned above. The resultant intense green coloured dye was monitored spectrophotometrically at 600 nm. Under the optimum working conditions the method is characterized by a sampling rate of 9h(-1), a linear calibration range of 0.5-15 mg L(-1) (absorbance=5.40×10(-2) [acetaldehyde, mg L(-1)], R(2)=0.998), a relative standard deviation (RSD) of 1.90% (n=10, acetaldehyde concentration of 2.5 mg L(-1)), and a limit of detection (LOD) of 12.3 μg L(-1). The LOD and sampling rate of the proposed method are superior to those of the conventional gas chromatographic (GC) method (LOD=93.0 μg L(-1) and sampling rate=4 h(-1)). The reliability of the proposed method was illustrated by the fact that spiked with acetaldehyde saliva samples yielded excellent recoveries (96.6-101.9%), comparable to those obtained by GC (96.4-102.3%) and there was no statistically significant difference at the 95% confidence level between the two methods when non-spiked saliva samples were analysed.
乙醇的摄入已知会增加口腔癌的可能性。此外，人们越来越关注长期使用含乙醇的漱口水与口腔癌之间可能存在的关联。乙醛，已知的致癌物质，是乙醇的第一代谢物，它可以在摄入或暴露于乙醇后在口腔中产生。本文报道了一种通过与 3-甲基-2-苯并噻唑啉酮腙（MBTH）和三氯化铁的显色反应在线测定唾液乙醛的气体扩散流动注射法。将乙醛样品和标准品（80μL）注入含有 NaCl 的供体流中，乙醛从供体流中通过气体扩散池的疏水性 Teflon 膜扩散到含有上述两种试剂的受体流中。生成的强烈绿色染料在 600nm 处进行分光光度法监测。在最佳工作条件下，该方法的采样率为 9h(-1)，线性校准范围为 0.5-15mgL(-1)（吸光度=5.40×10(-2) [乙醛，mgL(-1)]，R(2)=0.998），相对标准偏差（RSD）为 1.90%（n=10，乙醛浓度为 2.5mgL(-1))，检出限（LOD）为 12.3μg L(-1)。与传统的气相色谱（GC）方法（LOD=93.0μg L(-1)和采样率=4h(-1)）相比，该方法的 LOD 和采样率具有优势。通过向含有乙醛的唾液样品中添加乙醛来验证该方法的可靠性，回收率非常高（96.6-101.9%），与 GC （96.4-102.3%）获得的回收率相当，并且在分析未添加唾液样品时，两种方法之间在 95%置信水平下没有统计学上的显著差异。
