Novel Water-Soluble Cyclodextrin-Based Conjugated Polymer for Selective Host–Guest Interactions of Cationic Surfactant CTAB and Reverse FRET with Rhodamine B Tagged Adamantyl Guest

Abstract

A new water-soluble π-conjugated main-chain polymer P1 bearing a β-cyclodextrin (β-CD) pendant was designed and synthesized. The aggregation and disaggregation of P1 generated faded yellow-greenish and bright-yellow emissions, respectively. The inclusion complexation capability of P1 through β-CD pendant with a cationic surfactant cetyltrimethylammonium bromide (CTAB) guest and associative interactions of P1 with Fe 3+ through triazole spacers resulted in significantly enhanced and completely diminished emission profiles of P1 in pure water, respectively. Interestingly, ADRhB as another rhodamine B (RhB) tagged adamantyl guest was transformed into ADRhB(O), i.e., the open form of ADRhB, to generate RhB emission in the presence of Fe 3+ ion selectively for the pendent host β-CD of P1, and the further interaction of ADRhB(O)/Fe 3+ with P1 prevailed a completely quenched RhB emission via the inclusion complexation of adamantyl terminal of ADRhB(O) in β-CD. Moreover, stronger interactions of CTAB with β-CD further generated RhB emission of ADRhB(O) even in the presence of acceptor P1. Finally, a novel β-CD bearing water-soluble P1 with selective and strong interactions of CTAB toward disaggregation events in pure water, and further electrostatic repulsion and utilization of RhB via RhB-tagged adamantyl guest ADRhB(O) as a donor revealed the reversefluorescence resonance energy transfer (FRET) process of P1.

Dynamic Macromolecular Material Design—The Versatility of Cyclodextrin‐Based Host–Guest Chemistry

“…Thus,i tc ould be shown that the association can be influenced by steric factors in addition to the pure host/guest interactions,which is of utmost importance in the formation of supramolecular brushes.Ap-conjugated brush polymer was formed by Lin and co-workers. [100] An alternating polymer of thiophene and benzthiadiazole with grafted b-CD moieties formed aggregates in aqueous solution with ay ellow-greenish emission. Thea ddition of cetyl trimethylammonium bromide led to disassembly of the aggregates and restoration of ab right yellow emission.…”

Unprecedented Strong Photoluminescences Induced from Both Aggregation and Polymerization of Novel Nonconjugated β-Cyclodextrin Dimer

“…β-cyclodextrin (β-CD), a class of cyclic oligosaccharides with 7 d -glucose units, are known to be highly water-soluble, essentially nontoxic, and excellently biocompatible. , In the past decades, fluorescent CDs have attracted considerable interest and been extensively used as excellent fluorescent chemosensors for molecule recognition. − At present, nonfluorescent β-CDs are frequently converted into fluorescent CDs by the covalent attachment of one or two fluorophores to the CDs. However, there are still some problems with this method.…”

Reversible end-to-end assembly of selectively functionalized gold nanorods by light-responsive arylazopyrazole–cyclodextrin interaction

“…In fact, CTAB has a more than 20-fold higher binding constant to β-CD (6.5 × 10 4 M −1 ) [32] than unmodified azobenzenes (2.5 × 10 3 M −1 ) [33]. Therefore, the competitive binding of CTAB to β-CD has been applied previously, e.g., in sensing applications [34] or to enhance the water solubility of a cyclodextrin polymer [35]. On account of the experimental conditions that lead to a CTAB double layer formation around the AuNR, a significant amount of unbound CTAB may remain in solution and interact with host molecules.…”