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A new class of macrocyclic lanthanide complexes, Ln/DTPA-PDA-C(sub n), is developed for cellular labeling and magnetic resonance imaging (MRI) applications. These agents, combining with 3-dimensional MRI microscopy, have broad applications in imaging cell movement and localization in different biological systems in vivo.

Michel-addition polymerization of disulfide-based diacrylate and equimolar N-methyl ethylenediamine (MEDA) has formed ABB' type intermediates. The poly(amino ester)s have stimuli-sensitive disulfide bonds in the backbone that can be cleaved under dithiothreitol (DTT), affording these poly(amino ester)s with potential applications.

A water-soluble, biodegradable and fluorescent hyperbranched poly(amidoamine) with mannose groups on their surface (M-HPAMAM) has been successfully prepared, and the synthetic strategy includes Michael addition polymerization of diacrylamide with 1-(2-aminoethyl)piperazine and, subsequently, surface modification with mannosamine. The photoluminescence of M-HPAMAM was enhanced significantly due to the surface mannose groups. Incubation of E. coliwith M-HPAMAMs yielded brightly fluorescent bacteria clusters, but the fluorescent intensity of the aqueous solution lowered. This indicates that the M-HPAMAMs have strong affinity with bacteria due to their polyvalent interactions. Based on the size and the amount of bacteria clusters formed, the bacteria with the concentrations higher than 102cfu/mL can be detected. [ABSTRACT FROM AUTHOR]

The atom transfer radical dispersion polymerization of 4-vinylpyridine (4VP) in an ethanol/H2O mixture displayed two stages of polymerization; the first stage is the formation of a diblock copolymer with the polymerization rate of 1.21 mol·L-1·h-1before 1 h of polymerization, and the second is the main polymerization in micelles formed from the aggregation of the resultant block copolymers with the polymerization rate of 0.009 mol·L-1·h-1. The 2-bromoisobutyryl-terminated poly(ethylene glycol) methyl ether used in the polymerization acts as both a stabilizer and an initiator. The stable micelles with functional core were synthesized by a one-pot strategy via atom transfer radical dispersion copolymerization (ATRDCP) of 4VP and N,N‘-methylenebisacrylamide (MBA) in an ethanol/H2O solution for the first time. In the initial stage of polymerization, 4VP and MBA were copolymerized to form a block copolymer, PEG-b-(4VP-co-MBA), with pendent unreacted vinyl groups, and after phase separation at a critical chain length of P4VP-co-PMBA, the cross-linking reaction and polymerization occurred at the same time, resulting in cross-linked micelles. The volume ratio of ethanol/H2O had a big influence on the ATRDCP. An increase in the relative amount of ethanol in the solvent mixture will increase the solubility of P4VP in the polymerization system, the phase separation will be postponed, and the critical chain length of 4VP blocks at the phase separation becomes longer. As a result, the particles size and the 4VP content in the resultant micelles increase. The Au/polymer composite nanoparticles were successfully prepared by complexation of P4VP with HAuCl4and following reduction with NaBH4. [ABSTRACT FROM AUTHOR]