XAD-fractionation of "new" dissolved organic matter: is the hydrophobic fraction seriously underestimated?

LARA, RUBÉN JOSÉ; THOMAS, DAVID

MARINE CHEMISTRY

Elsevier

Lugar: Amsterdam; Año: 1994 p. 93 - 96

0304-4203

<!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:DE; mso-fareast-language:DE;} @page Section1 {size:612.0pt 792.0pt; margin:72.0pt 90.0pt 72.0pt 90.0pt; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} /* List Definitions */ @list l0 {mso-list-id:694115011; mso-list-type:hybrid; mso-list-template-ids:1179174070 67567631 67567641 67567643 67567631 67567641 67567643 67567631 67567641 67567643;} @list l0:level1 {mso-level-tab-stop:36.0pt; mso-level-number-position:left; text-indent:-18.0pt;} ol {margin-bottom:0cm;} ul {margin-bottom:0cm;} --> <!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} @page Section1 {size:612.0pt 792.0pt; margin:72.0pt 90.0pt 72.0pt 90.0pt; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> <!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} @page Section1 {size:612.0pt 792.0pt; margin:72.0pt 90.0pt 72.0pt 90.0pt; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> Freshly produced radiolabelled dissolved organic carbon (PDOC) from a marine diatom culture was fractionated on XAD-2 by NaOH/methanol elution. A large portion (32%) of the hydrophobic fraction could not be eluted by standard procedures. Only after severe hydrolysis and further extraction was it possible to recover most of this material. These findings indicate that usual XAD-2 fractionation methods may result in large underestimates of the hydrophobic fraction of PDOC.