Preparation and Investigation of coumarin-based chemosensors towards sensing of ions using UV studies in aqueous systems
- Authors: Kotze, Tyla
- Date: 2024-04
- Subjects: Chemistry, Analytic , Water chemistry , Ionic solutions , Aquatic ecology , Geochemistry
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/64116 , vital:73654
- Description: Humanity's unrelenting expansion has shown little regard for the environment, and this has resulted in tons of toxic heavy metal cations and anions being released into the environment through industrial, agricultural, electronic, and mining dumping. The release of these toxic heavy metals can cause diseases and sometimes lead to death, especially in third-world countries with low-income that reside in informal settlements, who suffer the most. Furthermore, the release of these toxins eventually finds their way back into the environment through bioaccumulation in fish, plants and animals. Although there is an ever need for the growth of these industries; low-cost, sensitive, selective, and organic-based sensors is a positive step forward in highlighting the need for environmental restoration and remediation, whilst striving to avoid unnecessary disease and death through this development. In this project, coumarin-based chemosensors for the detection of cationic and anionic species in aqueous and organic media are described. This project involves the synthesis of six different coumarin-based ether derivatives (E2-E5) and coumarin-based ester derivatives (H1-H2). FT-IR, 1H NMR and 13C NMR were used to confirm the structures of all sensors. The abilities of these novel compounds as chemosensors for detection of cations and anions were investigated using UV-vis analysis. These compounds displayed a favourable interaction with Fe2+ and Fe3+ ions with an increase in absorbance. Ether derivatives E2-E5 did not display any degree of selectivity or sensitivity towards the chosen anions. It was found that in the presence of FeCl2, sensors H1 and H2 displayed a degree of selectivities and further investigations were therefore carried out. From the titration experiments, the limit of detection, limit of quantification and association constants were determined. Job’s plot analyses were performed to determine the binding ratios, which was supported by Benesi-Hildebrand studies. The binding ratio between the sensors and metal cations during complexation was found to be 1:1. Reversibility studies were carried out using EDTA to determine whether the sensors could be reused. Molecular Modelling studies were used to determine the most preferred binding sites. Lastly, real-life application screenings were also run to determine if the sensors will be able to be used in real-life scenarios. , Thesis (MSc) -- Faculty of Science, School of Biomolecular & Chemical Sciences, 2024
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- Date Issued: 2024-04
Traditional birth attendants’ perceptions of their role in caring for women during childbirth in the Nyandeni sub-district
- Authors: Sinxi, Sisanda
- Date: 2023-12
- Subjects: Traditional Birth , Midwives--Nyandeni sub district
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/63012 , vital:73082
- Description: The role of Traditional Birth Attendants (TBAs) has been within remote communities for a long time. TBAs remain a major health resource in rural communities in developing countries as well as in some parts of urban areas. South Africa is a long way from effectively utilising TBAs as a community resource to enhance access to maternity services. This qualitative study, with an explorative, contextual, and descriptive design, included ten (n=12) TBAs aged between 38 and 56 years who met the inclusion criteria and were interviewed for the study. The objective of the study was to explore and describe TBAs’ perceptions of their role in caring for women during childbirth in the Nyandeni Sub-district. Data for this study was collected using face-to- face and individual semi-structured interviews, and field notes. Recorded data was transcribed verbatim and analysed using thematic analysis. Three main themes emerged, namely: TBAs perceive their role in caring for women as an essential service to women in the community; they believe that they possess the knowledge to conduct deliveries safely; and acknowledge that collaboration with the Department of Health could strengthen rural midwifery services. , Thesis (Ma) -- Faculty of Health Science, 2023
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- Date Issued: 2023-12