An investigation into the loss of preservatives from opthalmic solutions, during filtration sterilization
- Authors: Naidoo, Nadasen T
- Date: 1970
- Subjects: Filters and filtration , Sterilization
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3851 , http://hdl.handle.net/10962/d1012931
- Description: Most eye drops are dispensed in multi-dose containers, hence protection should be given against microbial contamination during use. To remain sterile during it's use, the solution should contain a preservative in such concentration so that it kills micro-organisms in a short time. It has been stated in the literature that the instillation of contaminated eye drops constitutes a greater danger than the intravenous injection of a contaminated solution since the cornea is nonvascular and lacks the normal antimicrobial defences of the blood stream. Amongst the preservatives used, those included in the official formulations for eye drops are Chlorhexidine Acetate, Phenyl Mercuric Nitrate, Benzalkonium Chloride, and to some extent Phenylethanol, which may be used in combination with Benzalkonium Chloride. The main purpose of this investigation has been to determine the adsorption of these preservatives by different filters during sterilization by filtration. Part 1, p. 2.
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- Date Issued: 1970
An investigation into chemical and biological assays of new compounds from aloes
- Authors: Mapp, R K
- Date: 1969
- Subjects: Medicinal plants -- Research -- South Africa , Botanical chemistry , Aloe -- Analysis , Aloe -- Research -- South Africa , Aloe , Aloin
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3850 , http://hdl.handle.net/10962/d1012830
- Description: The drug aloes has been known since earliest times and is mentioned in the Ebers papyrus of circa 1,500 B.C. Alexander the Great is reported to have sent a commission to Socotra to investigate the aloes grown there. The chemical composition of aloes is complex, and being of plant origin, subject to variation. Both the complexity of the chemical constituents and their biological variation has resulted in a very large volume of conflicting material being published on this drug export. Since aloes is used as a purgative for both human and veterinary use, it is obviously important that the dosage and consequently the active constituents, should comply to an accurate means of standardisation. To date, despite extensive world wide research into this drug such standardisation has not been achieved. Even the methods used for the assay of the principal constituent, aloin, vary considerably in their results, and to complicate matters new chemical principles have been isolated from aloes in recent years. Consequently the purpose of this work has been to investigate the main chemical assay methods currently in use, and to determine which was the most accurate, and why discrepancies occurred in the selected assay methods. furthermore the results obtained by chemical assay have been compared with those obtained by biological assay in an attempt to correlate aloin content with purgative activity. Newly isolated compounds have been investigated biologically for the first time, and the biological assays of the resinous, glycosidal and other compounds of aloes have been performed. Intro. p.1-2.
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- Date Issued: 1969