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Synthesis and characterization of polyazo-group IVB metallocene dichloride derivatives
Title
Synthesis and characterization of polyazo-group IVB metallocene dichloride derivatives.
Creator
Kloss, John Edward, Florida Atlantic University, Carraher, Charles E., Charles E. Schmidt College of Science, Department of Chemistry and Biochemistry
Abstract/Description
Reaction of Group IVB metallocene dichlorides with a monoaza dye yields a polymer in which the metal is bonded to a sulfonic and a hydroxyl group. The structure and bonding of the polymer was confirmed using infrared, mass spectrometry and 1H-NMR spectroscopy. Thermo and elemental analysis was used to confirm the presence of the metal. The stability of the polydye to the monomer unit was compared employing an argon laser in the visible region.
Date Issued
1993
PURL
http://purl.flvc.org/fcla/dt/14912
Subject Headings
Metallocenes, Organometallic polymers, Infrared spectroscopy, Azo compounds
Format
Document (PDF)
PURCHASE INTENTION AFTER EXPOSURE TO SAME VERSUS DIFFERENT ATTRIBUTES OF BRAND-NAME PRODUCTS: AN FNIRS STUDY
Title
PURCHASE INTENTION AFTER EXPOSURE TO SAME VERSUS DIFFERENT ATTRIBUTES OF BRAND-NAME PRODUCTS: AN FNIRS STUDY.
Creator
Chan, Jasmine Y., Wilcox, Teresa G., Florida Atlantic University, Department of Psychology, Charles E. Schmidt College of Science
Abstract/Description
When viewing advertisements, one could be exposed to new information about the product. During that time, one could construct ad hoc categories or simple attributes for the brand-name product. The current experiment used functional near-infrared spectroscopy (fNIRS) to measure bilateral frontal and temporal cortices to understand the contribution of constructing ad hoc categories and simple attributes on purchase intentions. The current experiment also examined the feasibility of using the...
Show moreWhen viewing advertisements, one could be exposed to new information about the product. During that time, one could construct ad hoc categories or simple attributes for the brand-name product. The current experiment used functional near-infrared spectroscopy (fNIRS) to measure bilateral frontal and temporal cortices to understand the contribution of constructing ad hoc categories and simple attributes on purchase intentions. The current experiment also examined the feasibility of using the tensor decomposition method compared to the grand averaging method in multidimensional fNIRS signal analysis. This is to see if tensor decomposition can maintain the pattern of hemodynamic response without losing the temporal dynamics and spatial array to find a more optimized time and regions of interest to average across. The current experiments consisted of two parts: 1) participants studied brand-name products for various ad hoc categories (Experiment 1) or various simple attributes (Experiment 2) and 2) pick for purchase brand-name products in a two-alternative forced choice purchase intention test. Three methods were used to analyze the hemodynamic response data: the grand averaging method, the tensor decomposition method, and the revised grand averaging method. The revised grand averaging method is the same as the grand averaging method but uses information from the tensor decomposition method to inform what time and channel to average across. There were behavioral priming benefits compared to products that were not studied. However, there were no differences across the study conditions. Results revealed processing benefits, not purchasing benefits, for brand-name products studied for different simple attributes as marked by changes in the left prefrontal cortex. The results from tensor decomposition revealed more details on the time and channels of interest than the grand averaging method. Findings suggest that studying different simple attributes of a brand-name product produces benefits in the purchase intention process. Also, findings suggest tensor decomposition is a feasible method for fNIRS signal analysis.
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Date Issued
2024
PURL
http://purl.flvc.org/fau/fd/FA00014392
Subject Headings
Consumer behavior, Psychology, Experimental, Near infrared spectroscopy
Format
Document (PDF)
Study of cell penetrating peptides with Raman spectroscopy and microscopy
Title
Study of cell penetrating peptides with Raman spectroscopy and microscopy.
Creator
Ye, Jing., Charles E. Schmidt College of Science, Department of Chemistry and Biochemistry
Abstract/Description
Cell penetrating peptides (CPPs) have drawn the attention of researchers due to their ability to internalize large cargos into cells including cancer cells. The mechanism(s) with which the peptides enter the cell, however, is/are not clear and full of controversy. The peptide conformations and their microenvironment in live cells had been unknown until the development of a technique developed in our lab. As a first demonstration of principle, penetratin, a 16-residue CPP derived from the...
Show moreCell penetrating peptides (CPPs) have drawn the attention of researchers due to their ability to internalize large cargos into cells including cancer cells. The mechanism(s) with which the peptides enter the cell, however, is/are not clear and full of controversy. The peptide conformations and their microenvironment in live cells had been unknown until the development of a technique developed in our lab. As a first demonstration of principle, penetratin, a 16-residue CPP derived from the Antennapedia homeodomain protein of Drosophila, was measured in single, living melanoma cells. Carbon-13 labeling of the Phe residue of penetratin was used to shift the intense aromatic ring-breathing vibrational mode from 1003 to 967 cm-1, thereby enabling the peptide to be traced in cells. Difference spectroscopy and principal components analysis (PCA) were used independently to resolve the Raman spectrum of the peptide from the background cellular Raman signals., On the basis of the position of the amide I vibrational band in the Raman spectra, the secondary structure of the peptide was found to be mainly random coil and b-strand in the cytoplasm, and possibly assembling as b-sheets in the nucleus. Next, label-free transportan was studied with the same methodology. The peptide, besides predominantly a-helix, adopted a significant portion of b-sheet conformation in the cytoplasm and nucleolus, which is different from the peptide in aqueous solution. The peptide microenvironment was also probed through H-bonding reported by the tyrosine Fermi doublet. Transportan displayed a tendency to accumulate in the cytoplasm over time which was unlike penetratin, which concentrated in the nucleus. The relative concentration of CPPs in various locations of live melanoma cells was directly estimated from the Raman spectra using average Phe concentration in the cell as an internal standard., The rapid entry and almost uniform cellular distribution of both peptides, as well as the lack of correlation between peptide and lipid Raman signatures, indicated that the mechanism of CPP internalization under the conditions of study was probably non-endocytotic. Last, transportan and penetratin were studied using polarized Raman spectroscopy for more detailed vibrational spectroscopic information of the two peptides in water and TFE solutions. The majority of the bands in the Raman spectra of the peptides were highly polarized, consistent with the high symmetry of aromatic ring side chain vibrational bands dispersed throughout the spectra. This work has provided new insights into the structure of CPPs in live cells and in solutions.
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Date Issued
2011
PURL
http://purl.flvc.org/FAU/3342344
Subject Headings
Peptides, Analysis, Infrared spectroscopy, Raman spectroscopy, Cellular signal transduction
Format
Document (PDF)
Study of Cell Penetrating Peptide Uptake and Cancer Cell Discrimination with Raman Spectroscopy and Microscopy
Title
Study of Cell Penetrating Peptide Uptake and Cancer Cell Discrimination with Raman Spectroscopy and Microscopy.
Creator
Cosme, Patrick Jason, Terentis, Andrew C., Florida Atlantic University, Charles E Schmidt College of Science, Department of Chemistry and Biochemistry
Abstract/Description
Cell penetrating peptides (CPPs) are short sequences of amino acids that excel in crossing the cellular membrane without inducing cytotoxicity Interest in these peptides stem from their ability to be attached, and grant their penetrating properties to, a variety of cargo In this work we have combined the application of Confocal Raman Microscopy (CRM) and Atomic Force Microscopy for the first time to examine the interactions of unlabeled Transportan (TP), one of the most well studied CPPs,...
Show moreCell penetrating peptides (CPPs) are short sequences of amino acids that excel in crossing the cellular membrane without inducing cytotoxicity Interest in these peptides stem from their ability to be attached, and grant their penetrating properties to, a variety of cargo In this work we have combined the application of Confocal Raman Microscopy (CRM) and Atomic Force Microscopy for the first time to examine the interactions of unlabeled Transportan (TP), one of the most well studied CPPs, with mammalian cells CRM’s capability to discriminate control and treated cell groups was verified by principal component analysis (PCA) and linear discriminant analysis (LDA) and was 93-100% accurate We’ve determined that at a concentration of 20 μM TP enters cells through a non-endocytotic mechanism, has a high affinity for the cytoplasm and membranes, and results in a significant increase in cellular stiffness Our work provides the first direct evidence of this cell-stiffening phenomenon SFTI-1, the smallest member of a bicyclic, cysteine rich class of CPPs, was examined by CRM to determine the potential role of cyclic structure on cellular uptake The peptide, along with monocyclic and linear analogs was heavy isotope labeled and incubated with mammalian cells at numerous concentrations and timespans Our work is the first SFTI-1 uptake study forgoing the use of fluorophore conjugates, which have been linked to artificial cellular uptake We demonstrate herein the absence of any CRM detectable uptake, providing the first evidence that SFTI-1 may not be a CPP Finally, CRM was applied to the discrimination of normal and basal cell carcinoma cells obtained from the same donor The use of patient matched cells avoids the normal biochemical variations that exist among individuals, ensuring that discrimination is based solely on the cell’s diseased state CRM spectra, analyzed by PCA and LDA, were capable of spectral discrimination with 100% accuracy Major differences in the cancerous cells were an increase in lipids and nucleic acids, and an overall decrease in protein We also demonstrate an enhancement in Raman signal through the use of an aluminum foil substrate, providing a practical approach for measuring cells with thin morphologies
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Date Issued
2016
PURL
http://purl.flvc.org/fau/fd/FA00004756
Subject Headings
Peptides--Analysis, Peptides--Therapeutic use, Peptides--Physiological transport, Cellular signal transduction, Raman spectroscopy, Infrared spectroscopy
Format
Document (PDF)
Rapid Analysis of Fecal Glucocorticoid Metabolites: Testing an Alternative Method for Analyzing Stress Markers in Chimpanzees
Title
Rapid Analysis of Fecal Glucocorticoid Metabolites: Testing an Alternative Method for Analyzing Stress Markers in Chimpanzees.
Creator
Litman, Benni, Broadfield, Douglas C., Harris, Michael S., Florida Atlantic University, Dorothy F. Schmidt College of Arts and Letters, Department of Anthropology
Abstract/Description
This study explores the application of two methods of spectroscopy; Near Infrared spectroscopy (NIR) and Fourier transform spectroscopy (FTIR) as alternative approaches for measuring glucocorticoid metabolites in chimpanzee feces. The goals of this study were twofold: The first was to determine if cortisol can be identified within the NIR and/or FTIR spectra of chimpanzee fecal hormone extract in ethanol solution. The second objective was to determine the capability of NIR and FTIR to predict...
Show moreThis study explores the application of two methods of spectroscopy; Near Infrared spectroscopy (NIR) and Fourier transform spectroscopy (FTIR) as alternative approaches for measuring glucocorticoid metabolites in chimpanzee feces. The goals of this study were twofold: The first was to determine if cortisol can be identified within the NIR and/or FTIR spectra of chimpanzee fecal hormone extract in ethanol solution. The second objective was to determine the capability of NIR and FTIR to predict FGM concentrations obtained using standard laboratory methods. Fecal glucocorticoid concentrations measured by Enzyme Immunoassay were used as the reference data of partial least square (PLS) regression of fecal extract NIR spectra and FTIR spectra. Low accuracies (NIR: R2 = 0.152; FTIR: R2 = 0.199) were obtained from regression models using data from both methods. Though this study did not successfully demonstrate the feasibility of using NIR and FTIR to qualify and quantify FGMs, it is likely not a reflection of the capabilities of the technology, but rather of appropriate sample types and preparation methods.
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Date Issued
2016
PURL
http://purl.flvc.org/fau/fd/FA00004723, http://purl.flvc.org/fau/fd/FA00004723
Subject Headings
Biosensors, Infrared spectroscopy, Metabolites -- Spectra, Primates as laboratory animals, Spectrum analysis -- Diagnostic use
Format
Document (PDF)
Using ATR-IR spectroscopy to study the conformation of cell-penetrating peptides
Title
Using ATR-IR spectroscopy to study the conformation of cell-penetrating peptides.
Creator
Fontoura, Luiza, Rezler, Evonne
Date Issued
2012-04-06
PURL
http://purl.flvc.org/fcla/dt/3351389
Subject Headings
Cell-Penetrating Peptides, Antennapedia Homeodomain Protein, Homeodomain Proteins --chemistry, Spectroscopy, Fourier Transform Infrared --methods, Spectrum Analysis, Amides --chemistry, Carrier Progeins
Format
Document (PDF)