Water-dispersible alkyne-bearing conjugated microporous poly-benzothiadiazoles were synthesized using thiol-yne chemistry to enhance water compatibility. The water compatible polymer networks were used as heterogeneous photocatalysts to generate singlet oxygen for the conversion of furoic acid to 5-hydroxy-2(5H)-furanone.

An efficient living ring-opening polymerization (ROP) of a permethoxylated epsilon-caprolactone [(OMe)CL] catalyzed by yttrium(III) isopropoxide was developed for the synthesis of degradable protein-resistant polymers [P(OMe)CL]. The lactone monomer was efficiently prepared from a reduced sugar, D-dulcitol. Kinetic studies of the ROP revealed a linear dependence of ln[M]0/[M] on polymerization time as well as a linear correlation between the number-averaged molecular weight (M(n)) and monomer conversion; both support it is a living polymerization. A series of block copolymers of our permethoxylated lactone with epsilon-caprolactone [P(OMe)CL-b-PCL] were synthesized and fully characterized. In thermal analyses only single T(g)s were observed in all the block copolymers, suggesting that P(OMe)CL and PCL blocks are fully miscible. Finally, surface plasmon resonance (SPR) sensograms demonstrated that both P(OMe)CL and the P(OMe)CL-b-PCL block copolymers exhibit excellent resistance to fibrinogen and lysozyme.

Nanogels have attracted much attention lately because of their many potential applications, including as nanocarriers for drug and gene delivery. Most nanogels reported previously, however, are not biodegradable, and their synthesis often requires the use of surfactants. Herein we report a surfactant-free method for the preparation of biodegradable, biocompatible, and stimuli-responsive cationic nanogels. The nanogels were synthesized by simply coaservating linear polymer precursors in mixed solvents followed by in situ cross-linking with homobifunctional cross-linkers. The versatility of this approach has been demonstrated by employing two different polymers and various cross-linkers to prepare nanogel particles with diameters ranging from 170 to 220 nm. Specifically, disulfide-containing tetralysine (TetK)- and oligoethylenimine (OEI)-based prepolymers were prepared and the subsequent nanogels were formed by covalently cross-linking the polymer coacervate phase. Nanogel particles are responsive to pH changes, increasing in size and zeta-potential with concomitant lowering of solution pH. Furthermore, as revealed by AFM imaging, nanogel particles were degradable in the presence of glutathione at concentrations similar to those in intracellular environment (10 mM). Both the nanogel and the polymer precursors were determined to exhibit minimal cytotoxicity against fibroblast 3T3 cells by flow cytometric analyses and fluorescent imaging. This study demonstrates a new surfactant-free method for preparing biodegradable, biocompatible, and stimuli-responsive nanogels as potential nanocarriers for the delivery of drugs and genes.

M13 phage have provided scaffolds for nanostructure synthesis based upon self-assembled inorganic and hard materials interacting with phage-displayed peptides. Additionally, phage display has been used to identify binders to plastic, TiO2, and other surfaces. However, synthesis of phage-based materials through the hybridization of soft materials with the phage surface remains unexplored. Here, we present an efficient “phage wrapping” strategy for the facile synthesis of phage coated with soluble, cationic polymers. Polymers bearing high positive charge densities demonstrated the most effective phage wrapping, as shown by assays for blocking non-specific binding of the anionic phage coat to a high pI target protein. The results establish the functional group requirements for hybridizing phage with soft materials, and solve a major problem in phage display – non-specific binding by the phage to high pI target proteins.