In this work, a rapid Fourier transform near infrared (FT-NIR) spectroscopic peroxide value (PV) method was developed and a prototype Continuous Oil Analysis and Treatment (COAT) system was assessed for monitoring and analytical purposes. High erucic acid rapeseed oil, a principle representative of triglyceride based oils suitable for biodegradable lubricating applications and mineral oil were used to test the methodology developed. / The FT-NIR PV method is based on a well defined stoichiometric reaction of triphenylphospine (TPP) with hydroperoxides to form triphenylphospine oxide (TPPO). A partial least squares calibration model for the prediction of PV was developed using the NIR spectral region where TPP and TPPO co-absorb. The resulting calibration was highly linear over the analytical range of 100PV. Validation of the method carried out by comparing the PV of PLS prediction to the results of AOCS iodometric procedures indicated an excellent concurrence between the two methods. By programming the FT-NIR spectrometer, the analytical procedure simply consists of the addition of TPP stock solution to oil sample, mixing, taking its spectrum and predicting PV value. Through selected testing procedures, the prototype COAT system utilizing FTIR spectroscopy, advanced sample handling system designs, and computer programming was proved to be effective in monitoring the oil quality and behavior of antioxidants in real time. / Both approaches offer combined advantages of speed, accuracy, low labor cost, automation, and environmental friendliness mainly derived from FTIR spectroscopy, and can serve as convenient means for routine quality control applications in oils and fats industry. Potential application based on the joint usage of the two methods in the obtaining of true value of oil stability was also presented in this text. (Abstract shortened by UMI.)

The process by which foods are browned during baking and roasting is attributed to the Maillard reaction. The interaction of the $ alpha$-hydroxycarbonyl moiety of a reducing sugar with an amino compound can result in a complex series of changes. The identification and isolation of the key intermediates, known as the Amadori rearrangement product (ARP) and Heyns rearrangement product (HRP), can provide a greater understanding of the browning process. / Fourier transform infrared (FTIR) analysis of 1-hydroxyacetane provided qualitative and quantitative information of the behavior of this $ alpha$-hydroxycarbonyl compound in various aqueous and non-aqueous solutions. / The carbonyl peaks (in the 1750-1700 $ rm cm sp{-1}$ absorption region) due to the keto and aldehydo forms of 1-hydroxyacetone (acetol) in the pure state and in deuterium oxide $ rm(D sb2O)$ were assigned. Upon addition of the acid-base catalysts (triethylamine, 5% NaOD and 5% DCl) additional peaks were detected in the alkene region (1700-1650 $ rm cm sp{-1})$ due to the formation of enediols by enolization. The examination of analogous hydroxycarbonyl structures (1-hydroxy-2-butanone, glyceraldehyde, glycoaldehyde and dihydroxyacetone) provided the means to confirm the assignments of the carbonyl and enediol bands. / The integrated intensity of the carbonyl peak of 1-hydroxyacetone centered at 1720 $ rm cm sp{-1}$ was determined for dilute solutions in $ rm D sb2O.$ The integrated molar absorptivity of the carbonyl band was calculated to be 3674 L/mol/cm. In addition, the effect of concentration and temperature on dimer dissociation was investigated. The effect of solvent and temperature on enolization was also studied. Time run analysis of the carbonyl-amine reaction of 1-hydroxyacetone with pyrrolidine provided the basis for a kinetic study of the rearrangement process in the early stage of Maillard reaction.

The application of Fourier transform infrared (FTIR) spectroscopy in the assessment of oil quality and stability and the determination of the degree and type (cis or trans) of unsaturation of fats and oils was investigated. FTIR spectroscopy was shown to provide a rapid means of monitoring changes in oils undergoing oxidation or subjected to thermal stress. Absorption bands associated with common primary and secondary oxidation products were identified by relating them to those of spectroscopically representative reference compounds, and a quantitative approach based on the use of oils spiked with these reference compounds as calibration standards was proposed. A sample-handling accessory based on a heated 25-mum transmission flow cell and heated input and output lines was developed to facilitate the rapid analysis of oils and premelted fats in their neat form. Using this system, an FTIR edible oil analysis package was developed to simultaneously analyze for trans content, cis content, iodine value (IV), and saponification number (SN) of neat fats and oils, using partial-least-squares (PLS) calibrations based on pure triglycerides. An automated transmission-based peak height method for isolated trans isomer determination using the characteristic trans absorption band at 967 cm -1 in the spectrum of a neat fat or oil, ratioed against the spectrum of a trans-free oil, was also developed. A subsequent validation study involving the analysis of more than 100 oil samples demonstrated concurrence between the trans data obtained by the PLS and peak height FTIR methods as well as between IV results obtained by FTIR analysis and gas chromatography. In addition, the internal consistency of the IV, cis, and trans FTIR predictions provided strong experimental evidence that the FTIR edible oil analysis package measures all three parameters accurately. A PLS-based IV/trans method was developed for a heated single-bounce horizontal attenuated total reflectance (SB-HATR) sample-

Three new quantitative Fourier transform infrared (FTIR) spectroscopic methods were developed to measure key lubricant condition monitoring parameters; total acid number (TAN), total base number (TBN), and moisture (H2O). All methods employ a common sample-handling accessory and are based on the addition of specific reagents designed to react stoichiometrically with target species in oils, with quantification being carried out using differential FTIR spectroscopy. The combined use of a stoichiometric reaction and differential spectroscopy overcomes the need for a reference oil, which has traditionally hindered quantitative analysis of lubricants by FTIR spectroscopy. Potassium hydroxide, trifluoroacetic acid (TFA) and 2,2-dimethoxypropane (DMP) were the stoichiometric reagents used to develop the FTIR TAN, TBN and H2 O methods, respectively. Calibrations were developed using either peak height measurements or partial least squares (PLS) regression and the methods were validated using standard addition techniques, as the ASTM (American Society of Testing and Materials) standard methods were not sufficiently reproducible to make valid comparisons. Validation of the methods indicated that the TAN, TBN and H2O methods had accuracies of +/-0.095 mg KOH/g, +/-0.5 mg KOH/g and +/-32ppm respectively and corresponding reproducibilities of +/-0.05 mg KOH/g, +/-0.17 mg KOH/g and +/-22 ppm. The TAN, TBN and H2O methods were implemented on a Continuous Oil Analysis and Treatment (COATRTM) System, integrating instrumentation, software and sample handling so as to provide packaged, user and environmentally friendly analytical methods that are alternatives to conventional ASTM wet chemical methods.

Liposomes are used as biocompatible carriers of drugs, peptides, proteins, plasmic DNA, antisense oligonucleotides or ribozymes, for pharmaceutical, cosmetic, and biochemical purposes. They are considered as effective drug delivery systems due to their colloidal size, easily controllable surface and membrane properties, large carrying capacity of drugs and biocompatibility. / This study was concerned with the stability of liposomes, their interaction at solid-liquid interfaces and their release of hydrophilic drug compounds. Either conventional liposomes containing lecithin and cholesterol, and Stealth® liposomes containing polyethylene glycol (PEG) 5000-lipids or PEG2000-lipids were investigated. Steric hindrance introduced by PEG chains proved to be influential in controlling liposome stability, interaction and drug release processes. Electrostatic forces were shown to be essential to the mechanisms and kinetics of liposome adsorption and colloidal stability, but not influential for the release of guanosine, used as a model hydrophilic drug. / Findings from this research improve the understanding of liposome interaction during drug delivery, give insight into the actions of liposomes in the body and may form the basis for improved liposome formulation. In addition, this research has developed a more comprehensive understanding of the role of PEG in controlling the colloidal stability, interfacial interactions of liposomes and drug transport kinetics across the lipid bilayers of liposomes. / Thesis (PhDAppliedScience)--University of South Australia, 2005.

Includes bibliographical references / 1 v. (various pagings) : ill ; 31 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Electrical and Electronic Engineering, 1985

Thèse (M.Sc.)--Université Laval, 2007. / Bibliogr.: f. 106-107. Publié aussi en version électronique dans la Collection Mémoires et thèses électroniques.

Proefschrift Universiteit van Amsterdam. / Met bibliogr., lit. opg. - Met samenvatting in het Nederlands.

Thèse--Univ. de Paris. / "Bibliographie": p. 115-125.

Thesis (Ph. D.)--University of Hong Kong, 2008. / Also available in print.