Block copolymers and uses thereof
An encoding/decoding apparatus and method using a low-density parity-check code (LDPC code) is disclosed. Basic column group information, serving as a set of information regarding positions of rows with weight 1, is extracted from a reference column in each column group of a predetermined parity-check matrix. Column group information transforms the positions of rows with weight 1 into positions whose lengths are within a required parity length. A parity-check matrix is generated according to the generated column group information. Data is encoded or decoded based on the generated parity-check matrix.
1. A micelle comprising both poly(ethylene glycol)-poly(propylene sulfide) (PEG-PPS) and poly(ethylene glycol)-poly(propylene sulfide)-poly(ethyleneimine) (PEG-PPS-PEI) block copolymers.
2. The micelle of claim 1 , wherein said micelle is between 20 and 50 nm in diameter.
3. The micelle of claim 1 , wherein the PEG-PPS-PEI copolymer comprises a bond between the PPS and PEI block that is labile in an endosome.
4. The micelle of claim 3 , wherein said labile bond is selected from the group consisting of vinyl ether, orthoester, acyl hydrazone, a disulfide bond, or a —N—PO 3 — group.
5. The micelle of claim 1 , wherein the PEG-PPS-PEI block further comprising a nucleic acid complexed to PEI.
6. The micelle of claim 5 , wherein said nucleic acid is selected from the group consisting of a single stranded oligonucleotide, an antisense oligonucleotide a small interfering RNA (siRNA), an aptamer, or plasmid DNA.
7. A pharmaceutical composition comprising the block copolymer of claim 1 and further comprising a pharmaceutically acceptable diluent.
8. A dry formulation comprising the micelles of claim 1 , wherein said formulation comprises less than 5% water by weight.
9. The formulation of claim 8 , wherein said formulation comprises less than 2% water by weight.
10. A method of transfecting a cell with a nucleic acid comprising contacting said cell with the micelle of claim 5 .
11. A method of transfecting a cell with a nucleic acid comprising contacting said cell with the micelle of claim 6 .