| 摘要: |
| 由于海水盐度大、有机质含量低,从海水中提取和纯化克级溶解性有机质(dissolved organic matter,DOM)一直十分困难。基于Bond Elut PPL固相萃取小柱法进行海水DOM固体样品提取的放大试验,建立DOM自动化调酸、PPL树脂吸附技术,最后形成提纯、冷冻干燥PPL-DOM(通过PPL树脂提取的DOM)完整工艺。采用元素分析、三维荧光光谱、红外光谱和固态13C核磁共振(NMR)波谱法进行样品表征。结果表明:(1)该方法对近海表层海水DOM回收率稳定在50%以上,搭建的提取装置DOM日吸附量可达230mg;(2)鳌山湾四个季节批次PPL-DOM整体分析结果表明,样品的元素组成和光谱特征相似,表明方法适用性和稳定性较好;(3)三种水生态环境的PPL-DOM13C NMR谱图显示样品的基本特征相似,以烷基碳、碳水化合物碳、芳香碳和羧基碳/酰胺碳为主,其中偶极去相(dipolar dephasing)谱显示了DOM前体化合物来源的差异。多种结果表明放大后的PPL固相萃取法可稳定提取克级DOM样品。 |
| 关键词: 海洋溶解性有机质 固相萃取 Bond Elut PPL 固态13C核磁共振 红外光谱 |
| DOI：10.11693/hyhz20220300047 |
| 分类号: |
| 基金项目:国家重点研发计划项目,2018YFA0605800号。 |
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| EXTRACTION OF REPRESENTATIVE MARINE DISSOLVED ORGANIC MATTER BY SOLID PHASE EXTRACTION AND CHARACTERIZATION IN INFRARED SPECTROMETRY AND SOLID-STATE 13C NUCLEAR MAGNETIC RESONANCE |
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WU Yi-Xin1, WANG Xiao-Cong1,2,3, ZHOU Zhen-Song1, HE Chen3, PAN Liang-Hao4, SONG Gui-Xue1
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1.Institute of Marine Science and Technology, Shandong University, Qingdao 266237, China;2.College of Science, China University of Petroleum(Beijing), Beijing 102249, China;3.State Key Laboratory of Heavy Oil Processing, China University of Petroleum(Beijing), Beijing 102249, China;4.Guangxi Mangrove Research Center of Guangxi Academy of Sciences, Beihai 536000, China
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| Abstract: |
| Due to high salinity and low concentration of marine dissolved organic carbon, it becomes a great challenge to extract and purify representative marine dissolved organic matter (DOM) in a gram-scale. We carried out a scale-up experiment based on the solid phase extraction (Bond Elut PPL) from seawaters, developed a set of customer-made device, and optimized the automatic procedure of SPE extraction, and finally PPL-DOMs were purified and freeze-dried. Elemental analysis, EEM (excitation emission matrix) fluorescence spectroscopy, Fourier transformed infrared spectroscopy and solid-state 13C NMR (nuclear magnet resonances) spectroscopy were used to characterize PPL-DOM samples. Results indicate that the extraction method was reliable with DOC recovery of greater than 50% and about 230 mg of DOM could be absorbed per day using the developed extraction device. In addition, the bulk analyses of elemental composition and spectral characteristics of DOM samples isolated from seawaters of the Aoshan Bay (Qingdao, China) in four seasons showed overall similarity, indicating in general that our method was applicable and reliable. Moreover, the 13C NMR spectra of PPL-DOM from samples of three different aquatic ecosystems showed similar characteristics to some extents in terms of aliphatic C, carbohydrate, aromatics, and carboxylis/amides, of which differences in the dipolar dephasing spectra stood out, reflecting different sources of precursor compounds in DOM. A variety of results show that the enlarged PPL solid phase extraction method can obtain DOM samples of gram magnitude with stable properties. |
| Key words: marine dissolved organic matter (DOM) solid Phase Extraction Bond Elut PPL 13C NMR fourier transform infrared spectroscopy |
