pH-responsive release of proteins from biocompatible and biodegradable reverse polymer micelles.

A reverse polymer micelle with a diameter of 100nm was prepared for a protein carrier releasing payloads in a pH-dependent manner. The reverse polymer micelle was made from an amphiphilic diblock copolymer of biodegradable poly(d,l-lactic-co-glycolic acid) (PLGA) and biocompatible poly(ethylene glycol) (PEG). PLGA having a terminal carboxyl group was additionally embedded in the micelle's PLGA layer via hydrophobic interaction.

Controlled release of protein drugs from newly developed amphiphilic polymer-based microparticles composed of nanoparticles.

A novel formulation of biodegradable microparticles was developed for the sustained release of peptide and protein drugs. The microparticles were formed by the aggregation of protein nanoparticles through water-in-oil (W/O) emulsion-lyophilization and subsequent solid-in-oil-in-water (S/O/W) emulsion-solvent evaporation. Amphiphilic copolymers were used as an emulsifier in the W/O emulsion and matrix of the microparticles.

Peptide-nucleic acids (PNAs) with pyrimido[4,5-d]pyrimidine-2,4,5,7-(1H,3H,6H,8H)-tetraone (PPT) as a universal base: their synthesis and binding affinity for oligodeoxyribonucleotides.

Peptide-nucleic acids (PNAs) including pyrimido[4,5-d]pyrimidine-2,4,5,7-(1H,3H,6H,8H)-tetraone (PPT) as a nucleobase were synthesized, and their binding affinity for the complementary oligodeoxyribonucleotides was investigated. We found that PNAs with one or two PPT(s) and natural nucleobases (i.e.

Binding affinity of a peptide nucleic acid containing pyrimido[4,5-d]pyrimidine-2,4,5,7-(1H,3H,6H,8H)-tetraone as a nucleobase for oligonucleotides.

In order to examine the potentiality as a universal nucleobase of pyrimido[4,5-d]pyrimidine-2,4,5,7-(1H,3H,6H,8H)-tetraone (PPT) incorporated in a peptide-nucleic acid (PNA), we synthesized a PNA with PPT, that is H-Gly-CCT(PPT)TCC-Lys-NH2, and investigated the duplex-formation ability of this PNA for the oligodeoxyribonucleotide, (5')GGAXAGG(3') (X = A, G, C or T) on the basis of the Tmvalue of a 1:1 mixture of the PNA and the oligonucleotide. As a result, we found that H-Gly-CCT(PPT)TCC-Lys-NH2 has good binding affinity for all the tested oligonucleotides, i.e.

Synthesis of a peptide nucleic acid oligomer with pyrimido[4,5-d]pyrimidine-2,4,5,7-(1H,3H,6H,8H)-tetraone as a nucleobase.

A peptide nucleic acid (PNA) oligomer containing pyrimido[4,5-d]pyrimidine-2,4,5,7-(1H,3H,6H,8H)-tetraone (PPT) as a nucleobase, which is expected to serve as a universal base, was synthesized.

Pyrimido[4,5-d]pyrimidine-2,4,5,7-(1H, 3H, 6H, 8H)-tetraone as a novel universal base.

A derivative of pyrimido[4,5-d]pyrimidine-2,4,5,7-(1H,3H,6H,8H)-tetraone (PPT), which may form various keto-enol tautomers suitable for forming base pairs with all natural bases, and is thus expected to serve as a universal base, was synthesized. The ability of PPT to form base pairs with natural bases was evaluated by UV analysis.