title: Disaggregation induced solvatochromic switch: a study of dansylated polyglycerol dendrons in binary solvent mixture.
abstract: A reversal in solvatochromic behaviour was observed in second and third generation glycerol based dansylated polyether dendrons in water on addition of a second solvent like methanol or acetonitrile. Below a certain percentage of the nonaqueous solvent there is a negative-solvatochromism observed and above that there is a switch to positive-solvatochromism. The negative-solvatochromism is attributed to the progressive disaggregation of the dendron aggregates by the nonaqueous solvent component. Once the disaggregation process is complete, positive-solvatochromism is exhibited by the dendron monomers. Higher the hydrophobicity of the dendron more is the amount of the second solvent required for disaggregation.
authors.affiliation: Department of Chemistry, National Institute of Technology Rourkela, India.
authors.forename: Usharani
authors.initials: U
authors.lastname: Subuddhi
authors.affiliation: Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036, India.
authors.forename: Prasanna K
authors.initials: PK
authors.lastname: Vuram
authors.affiliation: Laboratory of Bioorganic Chemistry, Department of Biotechnology and National Center for Catalysis Research, Indian Institute of Technology Madras, Chennai 600036, India. Electronic address: anjuc@iitm.ac.in.
authors.forename: Anju
authors.initials: A
authors.lastname: Chadha
authors.affiliation: Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036, India. Electronic address: mishra@iitm.ac.in.
authors.forename: Ashok K
authors.initials: AK
authors.lastname: Mishra
mesh_terms: D000873:Anthracenes / Q000737:chemistry*; D003619:Dansyl Compounds / Q000737:chemistry*; D005990:Glycerol / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry
chemical_list: D000873:Anthracenes; D003619:Dansyl Compounds; D011108:Polymers; D012997:Solvents; C501244:dendron; C043941:polyglycerol; D005990:Glycerol
keywords: Aggregation–disaggregation; Binary aqueous-nonaqueous solvent mixtures; Dansylated polyether dendrons; Fluorescence; Solvatochromism