Triblock copolymer-based luminescent organic-inorganic hybrids triggered by heating and fluoroquinolone antibiotics

Abstract

© 2015 Elsevier Ltd. Abstract The work introduces smart organic-inorganic hybrids with temperature- and substrate-induced quenching and sensitization of hexamolybdenum iodine cluster-centered luminescence based on iodine cluster salt [K(diglyme) (CH<inf>3</inf>CN)]<inf>2</inf>[Mo<inf>6</inf>I<inf>14</inf>] (1) and triblock copolymer (PEO)<inf>13</inf>(PPO)<inf>30</inf>(PEO)<inf>13</inf> (L64). Formation of supramolecular assembly of [Mo<inf>6</inf>I<inf>14</inf>]^2-, K⁺, and L64 molecules at fixed concentration conditions is manifested by specific cluster-centered luminescence. These supramolecular assemblies exhibit reversible luminescence quenching when temperature or concentration of L64 increases. The temperature-induced reversible aggregation of the L64-based organic-inorganic hybrids is followed by the reversible quenching of the cluster-centered luminescence. The ion-pairing equilibrium between the cluster anions and fluoroquinolones is shifted by the aggregation of the L64-based hybrids, which results in more enhanced quenching of the luminescence. These tendencies provide the route to sense the triblock copolymer-based phase transitions through the response of the cluster-centered luminescence.