The guanidinium group as a key part of water-soluble polymer carriers for siRNA complexation and protection against degradation.
Here, the preparation of a novel block copolymer consisting of a statistical copolymer N-(2-hydroxypropyl) methacrylamide-s-N-(3-aminopropyl) methacrylamide and a short terminal 3-guanidinopropyl methacrylamide block is reported. This polymer structure forms neutral but water-soluble nanosized complexes with siRNA. The siRNA block copolymer complexes are first analyzed using agarose gel electrophoresis and their size is determined with fluorescence correlation spectroscopy. The protective properties of the polymer against RNA degradation are investigated by treating the siRNA block copolymer complexes with RNase V1. Heparin competition assays confirm the efficient release of the cargo in vitro. In addition, the utilization of microscale thermophoresis is demonstrated for the determination of the binding strength between a fluorescently labeled polyanion and a polymer molecule.
Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany.
Ilja
I
Tabujew
Christoph
C
Freidel
Bettina
B
Krieg
Mark
M
Helm
Kaloian
K
Koynov
Klaus
K
Müllen
Kalina
K
Peneva
D000178:Acrylamides / Q000737:chemistry; D004722:Endoribonucleases / Q000378:metabolism; D019791:Guanidine / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D034741:RNA, Small Interfering / Q000737:chemistry* / Q000378:metabolism; D014867:Water / Q000737:chemistry
D000178:Acrylamides; D011108:Polymers; D034741:RNA, Small Interfering; D014867:Water; D004722:Endoribonucleases; D019791:Guanidine; C045985:methacrylamide
GPMA; HPMA; block copolymers; microscale thermophoresis; siRNA delivery