title: Spectroscopic properties of curcumin: orientation of transition moments.
abstract: Curcumin, a naturally occurring yellow-orange pigment with potent antioxidant and antitumor properties, has been attracting researchers from a wide range of fields including chemistry, spectroscopy, biology, and medicine. Ultrafast excited-state processes such as solvation and excited-state intramolecular hydrogen atom transfer (ESIHT) make curcumin an attractive agent for photodynamic therapy. In this report we present studies of linear dichroism and fluorescence anisotropy in oriented and isotropic media. The results show transition moments (long wavelength absorption and emission) oriented along the long molecular axis. Comparison of linear dichroism and excitation anisotropy in oriented and isotropic media suggests that excited-state intramolecular hydrogen atom transfer is probably associated with intramolecular conformational changes that can be constrained in highly stretched poly(vinyl alcohol) (PVA) film.
authors.affiliation: Department of Molecular Biology and Immunology, University of North Texas Health Science Center, 3500 Camp Bowie Boulevard, Fort Worth, Texas 76107, USA.
authors.forename: Anindita
authors.initials: A
authors.lastname: Mukerjee
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Sørensen
authors.forename: Amalendu P
authors.initials: AP
authors.lastname: Ranjan
authors.forename: Sangram
authors.initials: S
authors.lastname: Raut
authors.forename: Ignacy
authors.initials: I
authors.lastname: Gryczynski
authors.forename: Jamboor K
authors.initials: JK
authors.lastname: Vishwanatha
authors.forename: Zygmunt
authors.initials: Z
authors.lastname: Gryczynski
mesh_terms: D003474:Curcumin / Q000737:chemistry*; D005454:Fluorescence Polarization; D006859:Hydrogen / Q000737:chemistry; D011142:Polyvinyl Alcohol / Q000737:chemistry; D012997:Solvents / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet
chemical_list: D012997:Solvents; D006859:Hydrogen; D011142:Polyvinyl Alcohol; D003474:Curcumin