Intracellular Delivery of Charge-Converted Monoclonal Antibodies by Combinatorial Design of Block/Homo Polyion Complex Micelles.

Direct intracellular delivery of antibodies has gained much attention, although only a few agents have been developed, and none of them has reached clinical stages. The main obstacles here are the insufficient characteristics of delivery systems including stability and appropriate ability for intracellular antibody release. We tailored the structure of polyion complex (PIC) micelles by loading transiently charge-converted antibody derivatives for achieving enhanced stability, delivery to cytosol, and precise antigen recognition inside cells.

Induction of Secondary Structure through Micellization of an Oppositely Charged Pair of Homochiral Block- and Homopolypeptides in an Aqueous Medium.

Polyion complex (PIC) formation is an attractive method for obtaining molecular assemblies owing to their facile fabrication process in aqueous media, but more insights are required in order to control the higher-dimensional structures of polypeptide-based PICs. Herein, the PIC formation behavior of oppositely charged homochiral polypeptides, poly-L-lysine and poly(ethylene glycol)-b-poly(L-glutamate) (PEG-PLG), and their secondary structures are carefully studied in water. PIC formation takes place in a polymer concentration-dependent manner, and clear β-sheet formation is observed at polymer concentrations ≥0.

Determining the morphology of polystyrene-block-poly(2-vinylpyridine) micellar reactors for ZnO nanoparticle synthesis.

We report the use of reverse PS-b-P2VP diblock copolymer micelles as true nanoscale-sized reactor vessels to synthesize ZnO nanoparticles. The reverse micelles were formed in toluene and then sequentially loaded with zinc acetate dihydrate and tetramethylammonium hydroxide reactants. Moreover, high spatial resolution Z-contrast imaging and EDX spectroscopy techniques were used to confirm the segregation of the Zn cation to the core of the loaded micelles.

Nanoscale composition mapping of segregation in micelles with tapping-mode atomic force microscopy.

Under energy-dissipative cantilevered tip-sample interaction, phase imaging using tapping-mode atomic force microscopy enables compositional mapping of composites containing a harder inorganic phase at the nanometer scale, embedded in a polymer matrix. The contrast in the phase images is shown to be dependent on the variation in the elastic properties of the diblock copolymer reverse micelles loaded with zinc acetate. Tapping conditions are also shown to determine whether the contrast is positive or negative for the harder core of the loaded micelles, based on the competition between attractive and repulsive tip-sample interaction forces.

Gastric outlet obstruction secondary to acid ingestion in children.

Background/purpose: Gastric outlet obstruction (GOO) is a well-known complication of acid ingestion. However, most reports deal with adults. In this report, the authors present their experience with the treatment of acid-induced GOO in children.