Synthesis and self assembly of eosin functionalized amphiphilic block‐random copolymers prepared by ring opening metathesis polymerization

Abstract

Self assembly of block copolymers has gained considerable attention because of its potential use in various areas such as medical and biomedical applications, nanotechnology, and electronics. Herein, we present the synthesis and characterization of amphiphilic block‐random copolymers with a covalently incorporated pH‐sensitive dye, namely eosin. Ring opening metathesis polymerization was chosen for the preparation of well defined block copolymers and block‐random copolymers using a modified “2nd Generation Grubbs” initiator. The self assembly behavior of the block‐random copolymers in solution was studied by dynamic light scattering and small angle X‐ray scattering (SAXS). The influence of dye incorporation on the result of the self assembly process in methanol and ethanol was investigated and a subtle interplay of the nature of the selective solvent, the chain‐length of the block copolymer and the position of the dye within the polymer chain was established. Structural investigations using SAXS revealed a spherical shape and a core‐shell structure of exemplary block and block‐random copolymer micelles. UV–vis absorption and photoluminescence measurements revealed similar optical properties for polymer micelles in methanol compared to polymer solutions in THF. The pH‐sensitive behavior of the eosin dye was preserved within the micelles. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 401–413, 2008

Dye-functionalized polymers via ring opening metathesis polymerization: principal routes and applications

“…Adapted with permission from [29]. Copyright (2011) American Chemical Society molar ratios so that tailor-made block copolymers can be achieved easily [21,[40][41][42][43][44][45][46][47]. In addition to the tailored design of highly specific materials for bioimaging and visualization of tumor cells, even unspecifically labelled, self-assembled nanoparticles can be applied for e.g.…”

“…The optical properties of the dye were preserved within the aggregates, which makes this material useful for sensor applications [47]. The eosin containg micelle system was also investigated via SAXS (small angle X-ray scattering) measurements in solution, whereby the pH-sensitivity of the eosin dye was preserved within the accrued micelles [45]. Using the different approaches outlined above, precise placement of the dyes in either the hydrophilic or the hydrophobic block as well as on either chain is possible while the ratio of hydrophilic and hydrophobic blocks can be adjusted simply by employing adequate monomer/initiator Fig.…”

“…[2.2.1]Bicyclohept-5-enederivatives (norbornenes) are the most common monomers in ROMP, as a huge variety of different monomers can be [15][16][17], pentacene [18], tetracene [18] Anthracene [15,17], pyrene [19], benzothienobenzothiophene [20] --Anthracene [74] Fluorene [90] (Hetero)cycles Perylene bisimides [21][22][23][24], hexabenzocoronene [25][26][27], quinolone [26], pyrene [29] Phenanthroimidazole [30,31] perylene bisimides [21], quinizarine [32], phenoxynaphthacene [33] Perylene bisimides [21] Phenanthroimidazole [11], perylene bisimides [8], pyrene [9] Coumarin [79] Benzoxazole [81] Benzoxazole [76,90] a Triphenylmethane dyes (Dichloro)fluorescein [40], eosin [40] Eosin [41] Oregon Green 488 [42], rhodamin B [43], rhodamin [44], fluorescein [44], eosin [45][46][47] Fluorescein [10] Rhodamin, [10,…”

“…A wide range of suitable monomers has been copolymerized comprising (hetero)polyaromatic compounds [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33], and more sophisticated functionalities like conjugated oligomers [34][35][36][37][38][39], triphenylmethane [40][41][42][43][44][45][46][47], azo [48][49][50][51][52], or polymethine [53][54][55][56][57] dyes. Even transition metal coordination compounds of aluminum [58,59], iron [60], zinc [61][62][63], ruthenium [64, 65], europium …”

Phosphonic acid‐based amphiphilic diblock copolymers derived from ROMP

“…3 Ring-opening metathesis polymerization (ROMP) is a versatile technique for the preparation of well-defined block copolymers with narrow distribution of molecular weights. Several amphiphilic block copolymers obtained by the ROMP pathway have been investigated in the literature and were shown to form micelles and nanoparticles, [4][5][6][7][8][9][10][11][12][13][14] and used as drug delivery materials. [15][16][17] Phosphorus-containing polymers have broad application areas; besides their flameretardant properties, 18 they are also used in biomaterials for their adhesive properties to metals, bone, and dentin.…”