{"id":{"repo_id":"penn","oai_identifier":"oai:repository.upenn.edu:20.500.14332/31000"},"canonical_url":"https://search.dev.ndltd.org/etd/penn/oai:repository.upenn.edu:20.500.14332/31000","repository":{"repo_id":"penn","name":"University of Pennsylvania","base_url":"https://repository.upenn.edu/server/oai/request"},"display":{"title":"Cryptophane Derivatives as Gas Sensors and Hyperpolarized Xenon-129 Biosensors","abstract":"ABSTRACT CRYPTOPHANE DERIVATIVES AS GAS SENSORS AND HYPERPOLARIZED XENON-129 BIOSENSORS Najat S. Khan Professor Ivan J. Dmochowski This thesis describes the progress in the development of cryptophanes for three different applications: encapsulation of noble gases, 129Xe NMR biosensing for cancer detection, and the construction of molecular devices. A new water-soluble organic host molecule, tris-(triazole ethylamine) cryptophane, was synthesized for noble gas detection. This host was found to bind xenon with the highest affinity to date (KA = 42,000 ± 2,000 M-1 at 293 K). The same host was employed in the development of a radiometric assay for measuring the association constant of radon binding to a discrete molecular species, KA = 49,000 ± 12,000 M-1 at 293 K. For cancer detection by hyperpolarized 129Xe MRI, a new folate-conjugated cryptophane biosensor was developed that targets folate receptors (FR) overexpressed in a majority of cancer cells. The biosensor was relatively non-toxic at low micromolar concentrations required for imaging and was shown to selectively target cancer cells overexpressing FR. Flow cytometry results indicated a 10-fold higher cellular internalization in KB cells (FR+) than in HT-1080 cells (FR-). Finally, a smaller cavity tribenzylamine hemicryptophane was synthesized where the molecular structure and motions of the cage closely resembled that of molecular gyroscopes. It also provided a vehicle for exploring the structure and properties of multiple p-phenylene rotators within one molecule. The compact size and molecular motions of this gyroscope-inspired tribenzylamine hemicryptophane make it an attractive starting point for controlling the direction and coupling of rotators within molecular systems.","abstract_html":"ABSTRACT CRYPTOPHANE DERIVATIVES AS GAS SENSORS AND HYPERPOLARIZED XENON-129 BIOSENSORS Najat S. Khan Professor Ivan J. Dmochowski This thesis describes the progress in the development of cryptophanes for three different applications: encapsulation of noble gases, 129Xe NMR biosensing for cancer detection, and the construction of molecular devices. A new water-soluble organic host molecule, tris-(triazole ethylamine) cryptophane, was synthesized for noble gas detection. This host was found to bind xenon with the highest affinity to date (KA = 42,000 ± 2,000 M-1 at 293 K). The same host was employed in the development of a radiometric assay for measuring the association constant of radon binding to a discrete molecular species, KA = 49,000 ± 12,000 M-1 at 293 K. For cancer detection by hyperpolarized 129Xe MRI, a new folate-conjugated cryptophane biosensor was developed that targets folate receptors (FR) overexpressed in a majority of cancer cells. The biosensor was relatively non-toxic at low micromolar concentrations required for imaging and was shown to selectively target cancer cells overexpressing FR. Flow cytometry results indicated a 10-fold higher cellular internalization in KB cells (FR+) than in HT-1080 cells (FR-). Finally, a smaller cavity tribenzylamine hemicryptophane was synthesized where the molecular structure and motions of the cage closely resembled that of molecular gyroscopes. It also provided a vehicle for exploring the structure and properties of multiple p-phenylene rotators within one molecule. The compact size and molecular motions of this gyroscope-inspired tribenzylamine hemicryptophane make it an attractive starting point for controlling the direction and coupling of rotators within molecular systems.","abstract_has_math":false,"creators":["Khan, Najat S"],"institution":null,"degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Dr. Ivan J. Dmochowski","Dr. Virgil Percec","Dr. David Christianson, Dr. Bill Dailey"],"committee_chairs":[],"committee_members":[],"year":2011,"date_issued":"2011-08-12","date_published":"2011-08-12","updated_at":"2026-07-24T03:45:26Z","subjects":[],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://repository.upenn.edu/handle/20.500.14332/31000","outbound_label":"Repository record","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Dr. Ivan J. 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Khan Professor Ivan J. Dmochowski This thesis describes the progress in the development of cryptophanes for three different applications: encapsulation of noble gases, 129Xe NMR biosensing for cancer detection, and the construction of molecular devices. A new water-soluble organic host molecule, tris-(triazole ethylamine) cryptophane, was synthesized for noble gas detection. This host was found to bind xenon with the highest affinity to date (KA = 42,000 ± 2,000 M-1 at 293 K). The same host was employed in the development of a radiometric assay for measuring the association constant of radon binding to a discrete molecular species, KA = 49,000 ± 12,000 M-1 at 293 K. For cancer detection by hyperpolarized 129Xe MRI, a new folate-conjugated cryptophane biosensor was developed that targets folate receptors (FR) overexpressed in a majority of cancer cells. The biosensor was relatively non-toxic at low micromolar concentrations required for imaging and was shown to selectively target cancer cells overexpressing FR. Flow cytometry results indicated a 10-fold higher cellular internalization in KB cells (FR+) than in HT-1080 cells (FR-). Finally, a smaller cavity tribenzylamine hemicryptophane was synthesized where the molecular structure and motions of the cage closely resembled that of molecular gyroscopes. It also provided a vehicle for exploring the structure and properties of multiple p-phenylene rotators within one molecule. The compact size and molecular motions of this gyroscope-inspired tribenzylamine hemicryptophane make it an attractive starting point for controlling the direction and coupling of rotators within molecular systems."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["Doctor of Philosophy (PhD)"]},{"key":"dc:title","label":"Title","values":["Cryptophane Derivatives as Gas Sensors and Hyperpolarized Xenon-129 Biosensors"]}]}],"canonical_facts":{"dc:contributor.advisor":["Dr. Ivan J. Dmochowski","Dr. Virgil Percec","Dr. David Christianson, Dr. Bill Dailey"],"dc:creator":["Khan, Najat S"],"dc:date":["2023-05-17T06:17:13.000"],"dc:date.accessioned":["2023-05-22T17:56:37Z"],"dc:date.available":["2011-06-08T00:00:00Z"],"dc:date.issued":["2011-08-12"],"dc:description.abstract":["ABSTRACT CRYPTOPHANE DERIVATIVES AS GAS SENSORS AND HYPERPOLARIZED XENON-129 BIOSENSORS Najat S. Khan Professor Ivan J. Dmochowski This thesis describes the progress in the development of cryptophanes for three different applications: encapsulation of noble gases, 129Xe NMR biosensing for cancer detection, and the construction of molecular devices. A new water-soluble organic host molecule, tris-(triazole ethylamine) cryptophane, was synthesized for noble gas detection. This host was found to bind xenon with the highest affinity to date (KA = 42,000 ± 2,000 M-1 at 293 K). The same host was employed in the development of a radiometric assay for measuring the association constant of radon binding to a discrete molecular species, KA = 49,000 ± 12,000 M-1 at 293 K. For cancer detection by hyperpolarized 129Xe MRI, a new folate-conjugated cryptophane biosensor was developed that targets folate receptors (FR) overexpressed in a majority of cancer cells. The biosensor was relatively non-toxic at low micromolar concentrations required for imaging and was shown to selectively target cancer cells overexpressing FR. Flow cytometry results indicated a 10-fold higher cellular internalization in KB cells (FR+) than in HT-1080 cells (FR-). Finally, a smaller cavity tribenzylamine hemicryptophane was synthesized where the molecular structure and motions of the cage closely resembled that of molecular gyroscopes. It also provided a vehicle for exploring the structure and properties of multiple p-phenylene rotators within one molecule. The compact size and molecular motions of this gyroscope-inspired tribenzylamine hemicryptophane make it an attractive starting point for controlling the direction and coupling of rotators within molecular systems."],"dc:description.degree":["Doctor of Philosophy (PhD)"],"dc:identifier.uri":["https://repository.upenn.edu/handle/20.500.14332/31000"],"dc:title":["Cryptophane Derivatives as Gas Sensors and Hyperpolarized Xenon-129 Biosensors"],"dc:type":["Dissertation/Thesis"]},"updated_at":"2026-07-24T03:45:26Z"}