title: Fluorinated Photodynamic Therapy Device Tips and their Resistance to Fouling for In Vivo Sensitizer Release.
abstract: We describe progress on a one-step photodynamic therapy (PDT) technique that is simple: device tip delivery of sensitizer, oxygen and light simultaneously. Control is essential for their delivery to target sites to generate singlet oxygen. One potential problem is the silica device tip may suffer from biomaterial fouling and the pace of sensitizer photorelease is slowed. Here, we have used biomaterial (e.g. proteins, cells, etc.) from SQ20B head and neck tumors and whole blood for an assessment of fouling of the silica tips by adsorption. It was shown that by exchanging the native silica tip for a fluorinated tip, a better nonstick property led to an increased sensitizer output by ~10%. The fluorinated tip gave a sigmoidal photorelease where singlet oxygen is stabilized to physical quenching, whereas the native silica tip with unprotected SiO-H groups gave a slower (pseudolinear) photorelease. A further benefit from fluorinated silica is that 15% less biomaterial adheres to its surface compared to native silica based on a bicinchoninic acid assay (BCA) and X-ray photoelectron spectroscopy (XPS) measurements. We discuss how the fluorination of the device tip increases biofouling resistance and can contribute to a new pointsource PDT tool.
authors.affiliation: Department of Chemistry and Graduate Center, Brooklyn College, City University of New York, Brooklyn, NY.
authors.forename: Ashwini A
authors.initials: AA
authors.lastname: Ghogare
authors.affiliation: Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA.
authors.forename: Joann M
authors.initials: JM
authors.lastname: Miller
authors.affiliation: Department of Chemistry and Graduate Center, College of Staten Island, City University of New York, Staten Island, NY.
authors.forename: Bikash
authors.initials: B
authors.lastname: Mondal
authors.affiliation: Department of Chemistry and Graduate Center, College of Staten Island, City University of New York, Staten Island, NY.
authors.forename: Alan M
authors.initials: AM
authors.lastname: Lyons
authors.affiliation: Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA.
authors.forename: Keith A
authors.initials: KA
authors.lastname: Cengel
authors.affiliation: Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA.
authors.forename: Theresa M
authors.initials: TM
authors.lastname: Busch
authors.affiliation: Department of Chemistry and Graduate Center, Brooklyn College, City University of New York, Brooklyn, NY.
authors.forename: Alexander
authors.initials: A
authors.lastname: Greer
mesh_terms: D001672:Biocompatible Materials; D005461:Fluorine / Q000737:chemistry*; D006258:Head and Neck Neoplasms / Q000188:drug therapy*; D006801:Humans; D010778:Photochemotherapy / Q000295:instrumentation*
chemical_list: D001672:Biocompatible Materials; D005461:Fluorine