Are extracted materials truly representative of original samples? Impact of C18 extraction on CDOM optical and chemical properties
Some properties of dissolved organic matter (DOM) and chromophoric dissolved organic matter (CDOM) can be easily measured directly on whole waters, while others require sample concentration and removal of natural salts. To increase CDOM content and eliminate salts, solid phase extraction is often em...
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Frontiers Media S.A.
2016-02-01
|
| Series: | Frontiers in Chemistry |
| Subjects: | |
| Online Access: | http://journal.frontiersin.org/Journal/10.3389/fchem.2016.00004/full |
| _version_ | 1818132647107362816 |
|---|---|
| author | Andrea A Andrew Rossana eDel Vecchio Yi eZhang Ajit eSubramaniam Neil eBlough |
| author_facet | Andrea A Andrew Rossana eDel Vecchio Yi eZhang Ajit eSubramaniam Neil eBlough |
| author_sort | Andrea A Andrew |
| collection | DOAJ |
| description | Some properties of dissolved organic matter (DOM) and chromophoric dissolved organic matter (CDOM) can be easily measured directly on whole waters, while others require sample concentration and removal of natural salts. To increase CDOM content and eliminate salts, solid phase extraction is often employed. Biases following extraction and elution are inevitable, thus raising the question of how truly representative the extracted material is of the original. In this context, we investigated the wavelength dependence of extraction efficiency for C18 cartridges with respect to CDOM optical properties using samples obtained from the Middle Atlantic Bight (MAB) and the Equatorial Atlantic Ocean (EAO). Further, we compared the optical changes of C18 extracts and the corresponding whole water following chemical reduction with sodium borohydride (NaBH4).C18 cartridges preferentially extracted long-wavelength absorbing/emitting material for samples impacted by riverine input. Extraction efficiency overall decreased with offshore distance away from riverine input. Spectral slopes of C18-OM samples were also almost always lower than those of their corresponding CDOM samples supporting the preferential extraction of higher molecular weight absorbing material. The wavelength dependence of the optical properties (absorption, fluorescence emission and quantum yield) of the original water samples and their corresponding extracted material were very similar. C18 extracts and corresponding water samples further exhibited comparable optical changes following NaBH4 reduction, thus suggesting a similarity in nature (structure) of the optically active extracted material, independent of geographical locale. Altogether, these data suggested a strong similarity between C18 extracts and corresponding whole waters, thus indicating that extracts are representative of the CDOM content of original waters. |
| first_indexed | 2024-12-11T08:40:09Z |
| format | Article |
| id | doaj.art-03b7b8b463ac4eb19097dfa3d537b896 |
| institution | Directory Open Access Journal |
| issn | 2296-2646 |
| language | English |
| last_indexed | 2024-12-11T08:40:09Z |
| publishDate | 2016-02-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Chemistry |
| spelling | doaj.art-03b7b8b463ac4eb19097dfa3d537b8962022-12-22T01:14:16ZengFrontiers Media S.A.Frontiers in Chemistry2296-26462016-02-01410.3389/fchem.2016.00004170897Are extracted materials truly representative of original samples? Impact of C18 extraction on CDOM optical and chemical propertiesAndrea A Andrew0Rossana eDel Vecchio1Yi eZhang2Ajit eSubramaniam3Neil eBlough4University of MarylandUniversity of MarylandUniversity of MarylandLamont Doherty Earth Observatory at Columbia UniversityUniversity of MarylandSome properties of dissolved organic matter (DOM) and chromophoric dissolved organic matter (CDOM) can be easily measured directly on whole waters, while others require sample concentration and removal of natural salts. To increase CDOM content and eliminate salts, solid phase extraction is often employed. Biases following extraction and elution are inevitable, thus raising the question of how truly representative the extracted material is of the original. In this context, we investigated the wavelength dependence of extraction efficiency for C18 cartridges with respect to CDOM optical properties using samples obtained from the Middle Atlantic Bight (MAB) and the Equatorial Atlantic Ocean (EAO). Further, we compared the optical changes of C18 extracts and the corresponding whole water following chemical reduction with sodium borohydride (NaBH4).C18 cartridges preferentially extracted long-wavelength absorbing/emitting material for samples impacted by riverine input. Extraction efficiency overall decreased with offshore distance away from riverine input. Spectral slopes of C18-OM samples were also almost always lower than those of their corresponding CDOM samples supporting the preferential extraction of higher molecular weight absorbing material. The wavelength dependence of the optical properties (absorption, fluorescence emission and quantum yield) of the original water samples and their corresponding extracted material were very similar. C18 extracts and corresponding water samples further exhibited comparable optical changes following NaBH4 reduction, thus suggesting a similarity in nature (structure) of the optically active extracted material, independent of geographical locale. Altogether, these data suggested a strong similarity between C18 extracts and corresponding whole waters, thus indicating that extracts are representative of the CDOM content of original waters.http://journal.frontiersin.org/Journal/10.3389/fchem.2016.00004/fullextraction efficiencyCDOM fluorescenceNaBH4 reductionC18 extractionCDOM absorbance |
| spellingShingle | Andrea A Andrew Rossana eDel Vecchio Yi eZhang Ajit eSubramaniam Neil eBlough Are extracted materials truly representative of original samples? Impact of C18 extraction on CDOM optical and chemical properties Frontiers in Chemistry extraction efficiency CDOM fluorescence NaBH4 reduction C18 extraction CDOM absorbance |
| title | Are extracted materials truly representative of original samples? Impact of C18 extraction on CDOM optical and chemical properties |
| title_full | Are extracted materials truly representative of original samples? Impact of C18 extraction on CDOM optical and chemical properties |
| title_fullStr | Are extracted materials truly representative of original samples? Impact of C18 extraction on CDOM optical and chemical properties |
| title_full_unstemmed | Are extracted materials truly representative of original samples? Impact of C18 extraction on CDOM optical and chemical properties |
| title_short | Are extracted materials truly representative of original samples? Impact of C18 extraction on CDOM optical and chemical properties |
| title_sort | are extracted materials truly representative of original samples impact of c18 extraction on cdom optical and chemical properties |
| topic | extraction efficiency CDOM fluorescence NaBH4 reduction C18 extraction CDOM absorbance |
| url | http://journal.frontiersin.org/Journal/10.3389/fchem.2016.00004/full |
| work_keys_str_mv | AT andreaaandrew areextractedmaterialstrulyrepresentativeoforiginalsamplesimpactofc18extractiononcdomopticalandchemicalproperties AT rossanaedelvecchio areextractedmaterialstrulyrepresentativeoforiginalsamplesimpactofc18extractiononcdomopticalandchemicalproperties AT yiezhang areextractedmaterialstrulyrepresentativeoforiginalsamplesimpactofc18extractiononcdomopticalandchemicalproperties AT ajitesubramaniam areextractedmaterialstrulyrepresentativeoforiginalsamplesimpactofc18extractiononcdomopticalandchemicalproperties AT neileblough areextractedmaterialstrulyrepresentativeoforiginalsamplesimpactofc18extractiononcdomopticalandchemicalproperties |