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Solid phase extraction of phenolics using sorbents based on porous organic polymers
Heinrich, Kayla. 2023. Solid phase extraction of phenolics using sorbents based on porous organic polymers. Unpublished master's dissertation. Stellenbosch : Stellenbosch University [online]. Available at: https://scholar.sun.ac.za/items/80080136-6c04-4b9a-8c9d-29894761b6ed/
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| Language: | English |
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Stellenbosch : Stellenbosch University
2023
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| access_status_str | Open Access |
| author | Heinrich, Kayla |
| author2 | Mapolie, Selwyn F. |
| author_browse | Heinrich, Kayla Mapolie, Selwyn F. |
| author_facet | Mapolie, Selwyn F. Heinrich, Kayla |
| author_sort | Heinrich, Kayla |
| collection | Thesis |
| dc_rights_str_mv | Stellenbosch University |
| description | Heinrich, Kayla. 2023. Solid phase extraction of phenolics using sorbents based on porous organic polymers. Unpublished master's dissertation. Stellenbosch : Stellenbosch University [online]. Available at: https://scholar.sun.ac.za/items/80080136-6c04-4b9a-8c9d-29894761b6ed/ |
| format | Thesis |
| id | oai:scholar.sun.ac.za:10019.1/128407 |
| institution | Stellenbosch University (South Africa) |
| language | English |
| last_indexed | 2026-06-10T12:44:02.133Z |
| license_str | Other — see source repository |
| provenance_str_mv | Harvested via OAI-PMH from SUNScholar — Stellenbosch University Repository |
| publishDate | 2023 |
| publishDateRange | 2023 |
| publishDateSort | 2023 |
| publisher | Stellenbosch : Stellenbosch University |
| publisherStr | Stellenbosch : Stellenbosch University |
| record_format | dspace |
| source_str | SUNScholar — Stellenbosch University Repository |
| spelling | oai:scholar.sun.ac.za:10019.1/128407 Solid phase extraction of phenolics using sorbents based on porous organic polymers Heinrich, Kayla Mapolie, Selwyn F. De Villiers, Andre J. Stellenbosch University. Faculty of Science. Dept. of Chemistry and Polymer Science. Solid-phase synthesis Sorbents Phenols -- Analysis Porous materials UCTD Heinrich, Kayla. 2023. Solid phase extraction of phenolics using sorbents based on porous organic polymers. Unpublished master's dissertation. Stellenbosch : Stellenbosch University [online]. Available at: https://scholar.sun.ac.za/items/80080136-6c04-4b9a-8c9d-29894761b6ed/ Thesis (MSc)--Stellenbosch University, 2023. ENGLISH ABSTRACT: This thesis investigates the synthesis and characterization of a novel triazine-based porous organic polymer (POP), TAPT-DFP (2,4,6-tris(4-aminophenyl)-1,3,5-triazine with 1,4-diformylpiperazine), as well as two literature POPs, namely HP-TpBD (hypercrosslinked polymer from triformylphloroglucinol and benzidene) and PI-MA-PMDA (polyimide POP from melamine and pyromellitic dianhydride). It was confirmed through FTIR (ATR) and ¹³C CPMAS NMR spectroscopy as well as elemental analysis that the targeted POP architectures had been achieved. The successfully obtained insoluble POPs were then utilized in the proof-of concept dispersive solid phase extraction (dSPE) of four phenolic compounds, namely (-)-epicatechin, gallic acid, caffeic acid and rutin, from aqueous solution. The best performing POP, TAPT-DFP-1, was later employed as a sorbent in the extraction of phenolic compounds from wine samples. The novel imine-POP, TAPT-DFP, was successfully prepared by two synthetic methods to afford materials with different surface properties. Both were obtained by a solvothermal approach while TAPT-DFP-2 included a post-synthetic thermal treatment. Both materials were fully characterized by a range of solid state techniques including FTIR (ATR) and ¹³C CPMAS solid state NMR spectroscopy, elemental analysis, thermal gravimetric analysis, powder X-ray diffraction, scanning electron microscopy and BET analysis. The surface properties of these materials differed significantly where TAPT-DFP-1 exhibited a macroporous agglomerated surface with a surface area of 57 m²/g, while TAPT-DFP-2 had a shard-like appearance and was non-porous. The appearance of these properties in TAPT-DFP-2 suggested it would not be suitable as a sorbent material. The two literature POPs, HP-TpBD and PI-MA-PMDA were obtained by solvothermal and mechanochemical methods respectively. While their FTIR (ATR), ¹³C CPMAS NMR spectra, powder X-ray diffraction patterns and thermal profiles compared well to literature, surface analysis of these materials varied from that suggested in literature. HP-TpBD was found to be mainly microporous with a surface area of 295 m2/g and a flower-like surface morphology. PI-MA-PMDA showed an agglomerated morphology containing macropores with a very low surface area of 5 m²/g. TAPT-DFP-1, HP-TpBD and PI-MA-PMDA were employed in the dispersive solid phase extraction (dSPE) of (-)-epicatechin, gallic acid, caffeic acid and rutin standards from aqueous solution. The optimized dSPE parameters for TAPT-DFP-1 and PI-MA-PMDA included the adsorbent dosage (10 and 30 mg respectively), dispersive method (shaking), desorption solvent (MeOH) and desorption frequency (one cycle). The adsorbent capabilities of TAPT-DFP-1 were investigated which indicated possible multi-layer analyte retention on the POP scaffold by employing analyte-analyte interactions. In general, TAPT-DFP-1 was the best performing POP with nearly quantitative extraction of (-)-epicatechin, caffeic acid and rutin (>97%), while gallic acid was extracted 88% in individual extractions up to 50 ppm. TAPT-DFP-1, however, displayed no analyte selectivity between (-)-epicatechin, caffeic acid and rutin at concentrations below 50 ppm. Competitive extraction of the target analytes with TAPT-DFP-1, indicated the same trend as the individual extractions. HP-TpBD showed nearly quantitative adsorption percentages and selectivity for (-)-epicatechin and rutin up to 50 ppm (>98%) while gallic acid (52%) and caffeic acid (64%) were extracted to a lesser extent. PI-MA-PMDA was the least effective adsorbent with extraction percentages below 25% in individual extractions at initial concentrations of 50 ppm owing to its low surface area. It was, however, highly selective for rutin (87%) at 10 ppm compared to the other analytes which may be owing to the higher number of hydrogen bonds that can form between the POP and rutin. The elution recovery of the extracted analytes, at initial concentrations of 50 ppm, using MeOH was low for TAPT-DFP-1 (<50%) and HP-TpBD (<62%) while being much higher for PI-MA-PMDA (>80%). The excellent extraction behavior exhibited by TAPT-DFP-1 prompted its use in the extraction of phenolic compounds from white and red wine samples. Prior to extraction, the original concentrations of the target phenolic compounds were determined. All four analytes were detected in the dealcoholized red wine with the following concentrations: (-)-epicatechin 18.3 ppm, caffeic acid 6.0 ppm, gallic acid 70.5 ppm and rutin 15.6 ppm. In contrast, the dealcoholized white wine was found to contain (-)-epicatechin (1.7 ppm), caffeic acid (6.5 ppm) and gallic acid (0.9 ppm) while no rutin was detected in the sample. Positive extraction results were obtained using TAPT-DFP-1 as the sorbent where the extraction of caffeic acid in particular was 90% in white wine and 65% in red wine. The peak areas of several peaks originally present in the samples before extraction showed significant reduction after being subjected to extraction using TAPT-DFP-1. This suggests that some of the unidentified components in the wine samples were removed by the POP. AFRIKAANSE OPSOMMING: Hierdie tesis ondersoek die sintese en karakterisering van 'n nuwe triasien-gebaseerde poreuse organiese polimeer (POP), TAPT-DFP (2,4,6-tris(4-aminophenyl)-1,3,5-triazine saam met 1,4-diformylpiperazine), sowel as twee literatuur POPs, naamlik HP-TpBD (hiperkruisgebind polimeer vanaf triformylphloroglucinol en benzidene) en PI-MA-PMDA (polyimide POP vanaf melamine en pyromellitic dianhydride). Dit is deur FTIR(ATR) en 13C CPMAS NMR spektroskopie sowel as elementêre analise bevestig dat die geteikende POP argitekture bereik is. Die onoplosbare POPs wat suksesvol verkry is, is daarna gebruik in 'n bewys-van-konsep dispersiewe vaste fase ekstraksie (dVFE) van vier fenoliese verbindings, naamlik (-)-epicatechien, gallussuur, kafeïensuur en rutien, uit ‘n waterige oplossing. Die beste presterende POP, TAPT-DFP-1, is later as 'n sorbent gebruik in die ekstraksie van fenoliese verbindings uit wynmonsters. Die nuwe imien-POP, TAPT-DFP, is suksesvol voorberei deur twee sintetiese metodes om materiale met verskillende oppervlak eienskappe te gee. Beide is verkry deur 'n solvotermiese benadering terwyl TAPT-DFP-2 'n na-sintetiese termiese behandeling ingesluit het. Beide materiale is volledig gekarakteriseer deur 'n reeks vastetoestandtegnieke, insluitend FTIR (ATR) en 13C CPMAS vastetoestand KMR-spektroskopie, elementêre analise, termiese gravimetriese analise, poeier X-straaldiffraksie, skandeerelektronmikroskopie en BET-analise. Die oppervlak-eienskappe van hierdie materiale het betekenisvol verskil waar TAPT-DFP-1 'n makroporeuse geagglomereerde oppervlak met 'n oppervlakte van 57 m2/g getoon het, terwyl TAPT-DFP-2 'n skerfagtige voorkoms gehad het en nie-poreus was nie. Die voorkoms van hierdie eienskappe in TAPT-DFP-2 het voorgestel dat dit nie as 'n sorberende materiaal geskik sou wees nie. Die twee literatuur POP's, HP-TpBD en PI-MA-PMDA is verkry deur onderskeidelik solvotermiese en meganochemiese metodes te gebruik. Terwyl hul FTIR (ATR), 13C CPMAS KMR-spektra, poeierdiffraksiepatrone en termiese profiele goed vergelyk het met literatuur, het oppervlakanalise van hierdie materiale verskil van dié wat in literatuur voorgestel is. Daar is gevind dat HP-TpBD hoofsaaklik mikroporeus is met 'n oppervlakte van 295 m2/g en 'n blomagtige oppervlakmorfologie. PI-MA-PMDA het 'n geagglomereerde morfologie getoon wat makroporieë bevat met 'n baie lae oppervlakte van 5 m2/g. TAPT-DFP-1, HP-TpBD en PI-MA-PMDA is aangewend in die dispersiewe vastefase-ekstraksie (dVFE) van (-)-epicatechien, gallussuur, kafeïensuur en rutien standaarde uit ‘n waterige oplossing. Die geoptimaliseerde dSPE-parameters vir TAPT-DFP-1 en PI-MA-PMDA het die adsorbent dosis (10 en 30 mg onderskeidelik), dispersiewe metode (skud), desorpsie oplosmiddel (MeOH) en desorpsie frekwensie (een siklus) ingesluit. Masters 2023-03-04T13:54:48Z 2023-08-30T13:08:37Z 2023-03 2023-03-04T13:54:48Z 2023-08-31T09:18:37Z 2023-03-04T13:54:48Z 2023-08-31T09:18:37Z 2023-03 Thesis https://scholar.sun.ac.za/handle/10019.1/128407 en Stellenbosch University application/pdf xxi, 108 pages : illustrations application/pdf Stellenbosch : Stellenbosch University |
| spellingShingle | Solid-phase synthesis Sorbents Phenols -- Analysis Porous materials UCTD Heinrich, Kayla Solid phase extraction of phenolics using sorbents based on porous organic polymers |
| title | Solid phase extraction of phenolics using sorbents based on porous organic polymers |
| title_full | Solid phase extraction of phenolics using sorbents based on porous organic polymers |
| title_fullStr | Solid phase extraction of phenolics using sorbents based on porous organic polymers |
| title_full_unstemmed | Solid phase extraction of phenolics using sorbents based on porous organic polymers |
| title_short | Solid phase extraction of phenolics using sorbents based on porous organic polymers |
| title_sort | solid phase extraction of phenolics using sorbents based on porous organic polymers |
| topic | Solid-phase synthesis Sorbents Phenols -- Analysis Porous materials UCTD |
| url | https://scholar.sun.ac.za/handle/10019.1/128407 |
| work_keys_str_mv | AT heinrichkayla solidphaseextractionofphenolicsusingsorbentsbasedonporousorganicpolymers |