TitleAnalysis and characterization of consumer products by FTIR, Raman, chemometrics, and two dimensional ATR-FTIR correlation spectroscopy
NameZhang, Jun (author), Hall, Eugene (chair), Li, Jing (internal member), Warmuth, Ralf (internal member), Karaisz, Kenneth (outside member), Rutgers University, Graduate School - New Brunswick,
SubjectChemistry and Chemical Biology,
DescriptionMy research focused on two projects using Fourier Transform Infrared (FTIR), Micro-Raman spectroscopy, Chemometrics (Principle Component Analysis, PCA), and two-dimensional (2D) ATR-FTIR correlation spectroscopic techniques.
Project one involves method development and validation for the simultaneous determination of dimethicone and cyclomethicone in skin protectant ointments by FTIR. A unique FTIR method that utilizes two absorbance bands (1260 cm-1 and 808 cm-1) to determine the concentrations of dimethicone and cyclomethicone using two simultaneous equations was first time developed. The absorbances at two fixed wave numbers 1258.50 cm-1 and 800.00 cm-1 were used to calculate the concentrations of dimethicone and cyclomethicone. A series of comprehensive method validation experiments were designed and carried out. The simultaneous equation approach employed in the method was shown to be linear, accurate, precise, and specific.
Project two is to characterize fish oil supplements using ATR-FTIR, Micro-Raman, Principle Components Analysis, and 2D ATR-FTIR Correlation Spectroscopy. Most of the fish oil supplements claim active ingredient EPA and DHA on the labels, but the actual chemical forms (ethyl ester or triglyceride) are not indicated. A fast qualitative ATR-FTIR method was developed to distinguish between the ethyl ester and the triglyceride forms of fatty acids using the carbonyl band position. Chemometrics approach - Principal Component Analysis (PCA) was used to classify fish oil supplements successfully by grouping the FTIR and Raman spectra. PCA was also demonstrated as a powerful tool to screen fish oil supplements and identify the products that may be made by the same manufacturers with the same quality, but sold with different prices. A fish oil FTIR spectral library was also created for rapid searching and product comparison. In addition, an ATR-FTIR standard addition method was evaluated for quantitative analysis of active ingredients EPA and DHA esters in fish oil products. Lastly, two-dimensional FTIR correlation spectroscopy was first time used as a new technique to study temperature dependent spectral characteristics of fatty acids such as EPA and DHA esters to provide further spectral information of these polyunsaturated omega-3 fatty acids.
NoteIncludes bibliographical references
Noteby Jun Zhang
CollectionGraduate School - New Brunswick Electronic Theses and Dissertations
Organization NameRutgers, The State University of New Jersey
RightsThe author owns the copyright to this work.