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Synthesis of functional polymeric nanoparticles for the use in the formation of semi-permeable microcapsules
Thesis (MSc)--Stellenbosch University, 2020.
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| Format: | Thesis |
| Language: | en_ZA |
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Stellenbosch : Stellenbosch University
2020
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| _version_ | 1867613921841512448 |
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| access_status_str | Open Access |
| author | Du Plessis, Hildegard |
| author2 | Klumperman, Bert |
| author_browse | Du Plessis, Hildegard Klumperman, Bert |
| author_facet | Klumperman, Bert Du Plessis, Hildegard |
| author_sort | Du Plessis, Hildegard |
| collection | Thesis |
| dc_rights_str_mv | Stellenbosch University |
| description | Thesis (MSc)--Stellenbosch University, 2020. |
| format | Thesis |
| id | oai:scholar.sun.ac.za:10019.1/108370 |
| institution | Stellenbosch University (South Africa) |
| language | en_ZA |
| last_indexed | 2026-06-10T12:43:50.076Z |
| license_str | Other — see source repository |
| provenance_str_mv | Harvested via OAI-PMH from SUNScholar — Stellenbosch University Repository |
| publishDate | 2020 |
| publishDateRange | 2020 |
| publishDateSort | 2020 |
| publisher | Stellenbosch : Stellenbosch University |
| publisherStr | Stellenbosch : Stellenbosch University |
| record_format | dspace |
| source_str | SUNScholar — Stellenbosch University Repository |
| spelling | oai:scholar.sun.ac.za:10019.1/108370 Synthesis of functional polymeric nanoparticles for the use in the formation of semi-permeable microcapsules Du Plessis, Hildegard Klumperman, Bert Pfukwa, Rueben Stellenbosch University. Faculty of Science. Dept. of Chemistry and Polymer Science. Nanoparticles -- Therapeutic use -- Effectiveness Drug delivery systems Nanotechnology Polystyrene Artificial cells UCTD Thesis (MSc)--Stellenbosch University, 2020. ENGLISH ABSTRACT: Polymeric nanoparticles (NPs) have gained great interest in a wide range of fields, particularly in biomedical, optical and electronic applications. These NPs provide physical and chemical characteristics that make them highly attractive for these applications due to the accessibility of reactive functional groups on the particle surface. The aim of this thesis was to develop a method for the synthesis of functional polymeric NPs with tuneable sizes based on styrene (STY), maleic anhydride (MAnh) and divinylbenzene (DVB). NPs based on the highly crosslinked terpolymer of poly(STY-co-MAnh-co-DVB) were synthesized via batch and continuous polymerization processes with particle diameters ranging from circa 150 nm to 1000 nm. Due to limitations of NPs produced via a batch process, a continuous polymerization approach was developed for the synthesis of these NPs. Various experimental parameters were optimized, including flow rate, temperature, initiator, monomer and crosslinker concentrations. It was found that by optimization of these parameters, particle size and yield could be controlled. The presence of the reactive maleic anhydride, allows for easy introduction of various functionalities. In this study, the NPs were modified first with 3-aminophenyl boronic acid to introduce a boronic acid (BA) functionality, followed by the modification with 1,3-propandiol to introduce a boronate ester (BE) functionality. These modified NPs were ideal candidates for the stabilization of Pickering emulsions. The modified NPs were used to form microcapsules via inverse Pickering emulsions using water-soluble dextrin with multiple 1,2-hydroxyl groups to crosslink the capsules via the BE functionality present on the NPs. The intended end use of these microcapsules is for the encapsulation of delicate materials such as live bacteria or mammalian cells that could be used as a model system for drug delivery applications. In order to make this process a viable option for use in delivery applications, the redispersion of the capsules in an aqueous medium is required. Redispersion could not be achieved, and thus led to the investigation of water-in-water emulsions. Water-in-water emulsions were prepared based on aqueous solutions of poly(ethylene glycol) (PEG) and dextrin. Optimization of PEG molecular weight and concentration as well as dextrin concentration was done in order to successfully form immiscible aqueous solutions of PEG and dextrin. The functionality of the modified NPs was varied in order to achieve an improved kinetic drive of the particles to the interface of the emulsion droplets. AFRIKAANSE OPSOMMING: Polimeriese nanopartikels (NPs) het groot belangstelling in 'n wye verskeidenheid velde gewek, veral in biomediese, optiese en elektroniese toepassings. Hierdie NPs bied fisiese en chemiese eienskappe wat dit baie aantreklik maak vir hierdie toepassings as gevolg van die toeganklikheid van reaktiewe funksionele groepe op die partikeloppervlak. Die doel van hierdie tesis was om 'n metode te ontwikkel vir die sintese van funksionele polimeer NPs met verstelbare groottes, gebaseer op stireen (STI), maleïne-anhidried (MAnh) en divinylbenseen (DVB). NPs gebaseer op die kruis gekoppelde terpolimeer van poli(STI-ko-MAnh-ko-DVB) is gesintetiseer deur middel van bondel- en deurlopende polimerisasieprosesse met partikeldiameters wat wissel tussen ongeveer 150 nm tot 1000 nm. As gevolg van die beperkings van NPs wat deur 'n groepproses geproduseer word, is 'n deurlopende polimerisasie benadering ontwikkel vir die sintese van hierdie NPs. Verskeie eksperimentele parameters is geoptimaliseer, insluitend die vloeitempo, temperatuur, inisieerder, monomeer en kruiskoppelaar konsentrasies. Daar is gevind dat deur die optimalisering van hierdie parameters, partikelgrootte en opbrengs beheer kon word. Die teenwoordigheid van die reaktiewe maleïne-anhidried maak dit moontlik om verskeie funksionaliteite maklik in te voer. In hierdie studie is die NPs eerstens met 3-aminofenielboorsuur aangepas om 'n boorsuur (BS) funksionaliteit in te stel, gevolg deur die aanpassing met 1,3- propaandiol om 'n boronaat-ester (BE) funksionaliteit in te stel. Hierdie aangepaste NPs was ideale kandidate vir die stabilisering van Pickering-emulsies. Die gemodifiseerde NPs is gebruik om mikrokapsules te vorm via inverse Pickeringemulsies met behulp van wateroplosbare dekstrine met veelvuldige 1,2-hidroksied groepe om die kapsules te kruisverbind deur gebruik te maak van die BEfunksionaliteit wat op die NPs beskikbaar is. Die beoogde eindgebruik van hierdie mikrokapsules is vir die inkapsulering van delikate materiale soos lewende bakterieë of soogdierselle wat gebruik kan word as 'n modelstelsel vir toediening van medisyne. Om hierdie proses 'n lewensvatbare opsie te maak vir gebruik in afleweringstoepassings, is die herverdeling van die kapsules in 'n waterige medium nodig. Herverdeling kan nie bereik word nie, en het dus gelei tot die ondersoek van water-in-water-emulsies. Water-in-water-emulsies is voorberei op grond van waterige oplossings van poli(etileenglikol) (PEG) en dekstrine. Die optimalisering van PEG molekulêre gewig en konsentrasie, sowel as dekstrinekonsentrasie, is gedoen om suksesvol onmengbare waterige oplossings van PEG en dekstrin te vorm. Die funksionering van die gemodifiseerde NPs was uiteenlopend ten einde 'n verbeterde kinetiese aandrywing van die deeltjies tot die koppelvlak van die emulsiedruppels te bewerkstellig. Masters 2020-02-20T10:25:14Z 2020-04-28T15:11:09Z 2020-02-20T10:25:14Z 2020-04-28T15:11:09Z 2020-02 Thesis http://hdl.handle.net/10019.1/108370 en_ZA Stellenbosch University xviii, 109 pages : illustrations application/pdf Stellenbosch : Stellenbosch University |
| spellingShingle | Nanoparticles -- Therapeutic use -- Effectiveness Drug delivery systems Nanotechnology Polystyrene Artificial cells UCTD Du Plessis, Hildegard Synthesis of functional polymeric nanoparticles for the use in the formation of semi-permeable microcapsules |
| title | Synthesis of functional polymeric nanoparticles for the use in the formation of semi-permeable microcapsules |
| title_full | Synthesis of functional polymeric nanoparticles for the use in the formation of semi-permeable microcapsules |
| title_fullStr | Synthesis of functional polymeric nanoparticles for the use in the formation of semi-permeable microcapsules |
| title_full_unstemmed | Synthesis of functional polymeric nanoparticles for the use in the formation of semi-permeable microcapsules |
| title_short | Synthesis of functional polymeric nanoparticles for the use in the formation of semi-permeable microcapsules |
| title_sort | synthesis of functional polymeric nanoparticles for the use in the formation of semi permeable microcapsules |
| topic | Nanoparticles -- Therapeutic use -- Effectiveness Drug delivery systems Nanotechnology Polystyrene Artificial cells UCTD |
| url | http://hdl.handle.net/10019.1/108370 |
| work_keys_str_mv | AT duplessishildegard synthesisoffunctionalpolymericnanoparticlesfortheuseintheformationofsemipermeablemicrocapsules |