Fluorescently tagged star polymers by living radical polymerisation for mucoadhesion and bioadhesion

Abstract

The synthesis of 3-, 5-and 8-arm dimethylaminoethyl methacrylate star polymers are reported, final M n (PDI) = 12.2 K (1.09), 18.9K (1.10) and 38.4 K (1.11), respectively. The synthesis of 3-arm methyl methacrylate and dimethylaminoethyl methacrylate block co-polymer stars is also described. Living polymerisation occurred in all cases providing well defined stars with predictable molecular weights and narrow polydispersity. A fluorescent tag, 2-(8-methacryloyloy-3,6-dioxaoctyl)thioxantheno[2,1,9-dej]isoquinoline-1,3-dione, derived from a commercially available pigment, was incorporated into the star polymers. The fluorescence spectra of the polymers prepared were recorded over a range of pH and the peak emission frequency and intensity have been reported, k ex = 462 nm. All of the multi-arm polymers exhibit fluorescence across a broad pH range with maximum emission at pH 4. A 3-arm star polymer has been demonstrated to show good bioadhesion in rat tissue. A reduced adhesion in epithelial tissues not covered by a viscoelastic mucus gel indicates an increased tendency for mucoadhesion over bioadhesion.

Antibacterial Effects of Poly(2-(dimethylamino ethyl)methacrylate) against Selected Gram-Positive and Gram-Negative Bacteria

“…Hostasol (thioxantheno [2,1,9-def]isochromene-1,3-dione) (389.5 Da, CAS Registry Number: 14121-49-4) was supplied by Clariant (Muttenz, Switzerland). Fluorescent hostasol-conjugated pDMAEMA was prepared as described previously 14 , using ethyl-2-bromo isobutyrate as the polymerisation initiator and lowering the pH of the final isolated polymer aqueous solution to pH 5.5 with 0.5 M aqueous HCl before freeze-drying. Hostasol was used as a fluorescent marker to track the polymer in imaging and flow cytometry studies.…”

Transfection of Immortalized Keratinocytes by Low Toxic Poly(2-(Dimethylamino)Ethyl Methacrylate)-Based Polymers

“…Hostasol-methacrylate monomer (2-(8- (Fig. 1) was prepared from the precursor Hostasol-anh as described in the literature [35].…”

Resistance of Staphylococcus aureus to the cationic antimicrobial agent poly(2-(dimethylamino ethyl)methacrylate) (pDMAEMA) is influenced by cell-surface charge and hydrophobicity

“…Synthesis of pDMAEMA analogues. Unconjugated and fluorescent hostasol-conjugated pDMAEMA analogues were produced by transfer radical polymerization according to our previously described methods (Limer et al, 2006;Rawlinson et al, 2010b). The molecular mass and polydispersity index of unconjugated linear pDMAEMA were 12.8 kDa and 1.16, respectively.…”

“…In addition, biofilm formation confers increased resistance to antimicrobial agents due to slow growth (Evans et al, 1994;Roberts & Stewart, 2004), induction of stress-response genes (Adams & McLean, 1999), exclusion of antimicrobials due to the physical and/or chemical structure of the exopolysaccharide matrix (Lewis, 2001) and increased presence of persister cells (Lewis, 2001 Cationic agents have the potential for prevention of infections associated with indwelling medical devices (Lowe et al, 2000;Yang et al, 2007). Poly(2-(dimethylamino ethyl)methacrylate) (pDMAEMA) is a mucoadhesive antimicrobial polymer that is cationic when dissolved in acidified media or if quaternized with alkylating agents (Bütün et al, 2001;Limer et al, 2006). It can be produced cheaply and at high yield and purity by atom transfer radical polymerization (Haddleton et al, 1999).…”