2893-48-3Relevant articles and documents
pH-Sensitive Polycations for siRNA Delivery: Effect of Asymmetric Structures of Tertiary Amine Groups
Yang, Qinping,Dong, Yanliang,Wang, Xuanyu,Lin, Zhihao,Yan, Mingyu,Wang, Weiwei,Dong, Anjie,Zhang, Jianhua,Huang, Pingsheng,Wang, Changrong
, (2021/03/31)
pH-sensitive polyelectrolytes provide enormous opportunity for siRNA delivery. Especially, their tertiary amine structures can not only bind genes but also act as pH-sensitive hydrophobic structure to control genes release. However, the influence of molecular structures on siRNA delivery still remains elusive, especially for the asymmetric alkyl substituents of the tertiary amine groups. Herein, a library of N-methyl-N-alkyl aminoethyl methacrylate monomers (MsAM) with asymmetric alkyl substituents on the tertiary amine group is synthesized and used to prepare a series of tri-block polycationic copolymers poly(aminoethyl methacrylate)-block-poly (N-methyl-N-alkyl aminoethyl methacrylate)-block-poly(ethylene glycol methacrylate) (PAMA-PMsMA-PEG). And the properties of these polycations and their self-assembled micelles are characterized, including molecular structure, proton buffering capacity, pH-sensitivity, size, and zeta potential. With the length increase of one alkyl substituent, the proton buffering capacity of both monomers and polycations is demonstrated to be narrowed down. The siRNA delivery efficiency and cytotoxicity of these micelles are also evaluated on HepG2 cells. In particular, poly(aminoethyl methacrylate)-block-poly(N-methyl-N-ethyl aminoethyl methacrylate)-block-poly(ethylene glycol methacrylate) (PAMA-PMEMA-PEG) elicited the best luciferase knockdown efficiency and low cytotoxicity. Besides, PAMA-PMEMA-PEG/siRRM2 also induced significant anti-tumor activity in vitro. These results indicated PAMA-PMEMA-PEG has potential for further use in the design of gene vehicles with the improved efficiency of siRNA delivery.
Multimodal Anion Exchange Matrices
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Paragraph 0081; 0083; 0087, (2015/11/23)
The invention discloses a separation matrix which comprises a plurality of separation ligands, defined by the formula R1-L1-N(R3)-L2-R, immobilized on a support, wherein R1 is a five- or six-membered, substituted or non-substituted ring structure or a hydroxyethyl or hydroxypropyl group; L1 is either a methylene group or a covalent bond; R2 is a five- or six-membered, substituted or non-substituted ring structure; L2 is either a methylene group or a covalent bond; R3 is a methyl group; and wherein if R1 is a hydroxyethyl group and L1 is a covalent bond, R2 is a substituted aromatic ring structure or a substituted or non-substituted aliphatic ring structure.
STRUCTURE OF PRODUCTS AND PARTIAL CHAIN TRANSFER CONSTANTS IN THE RADICAL TELOMERIZATION OF ETHYLENE WITH 3-BUTYL-1,3-OXAZOLIDINE
Germash, A. V.,Zorin, V. V.,Zlotskii, S. S.,Rakhmankulov, D. L.,Terentev, A. B.
, p. 477 - 480 (2007/10/02)
The radical telomerization of ethylene with 3-butyl-1,3-oxazolidine, initiated by tert-butyl peroxide, at 140 deg C leads to the formation of telomeric N-butyl-N-alkylformamides.The partial chain transfer constants were determined for the growing telomeric radicals.
