Acid-labile poly(amino alcohol ortho ester) based on low molecular weight polyethyleneimine for gene delivery

2017 ◽  
Vol 32 (3) ◽  
pp. 349-361 ◽  
Author(s):  
Jun Wang ◽  
Lei Zhang ◽  
Xin Wang ◽  
Shengxiang Fu ◽  
Guoqing Yan
Keyword(s):  
Molecular Weight ◽  
Amino Alcohol ◽  
Water Solubility ◽  
Transfection Efficiency ◽  
Enzymatic Digestion ◽  
Low Molecular Weight ◽  
Hydroxyl Groups ◽  
Ortho Ester ◽  
Human Neuroblastoma ◽  
Acid Labile

A series of acid-labile poly(amino alcohol ortho ester) (POEeis) were synthesized through ring-opening polymerization between diglycidyl ethers with ortho ester bonded and low molecular weight polyethyleneimine by various feed molar ratios. The obtain POEei 1 and POEei 2 exhibited clear kinetic of degradation and condensed plasmid DNA into nanoparticles of suitable sizes (250–300 nm) and positive zeta potentials (+20–30 mV) while protecting DNA from enzymatic digestion. Further, these polymers have uniform distribution of abundant hydroxyl groups, which could improve their water solubility, biocompatibility, and lower protein adsorption. Significantly, ortho ester groups in POEeis main-chains could hydrolyze rapidly at acidic endosomal pH, resulting in intracellular DNA release and diminished material toxicity. MTT assay revealed that all the polymers exhibited much lower cytotoxicity than 25 kDa PEI in the human neuroblastoma SH-SY5Y cells. Moreover, the transfection efficiency of POEei 1 was higher than 25 kDa PEI in serum-free medium or 10% serum medium.

Low Molecular Weight PEI-Based Vectors via Acid-Labile Ortho Ester Linkage for Improved Gene Delivery

2016 ◽  
Vol 16 (8) ◽  
pp. 1175-1187 ◽  
Author(s):  
Lei Zhang ◽  
Min Yu ◽  
Jun Wang ◽  
Rupei Tang ◽  
Guoqing Yan ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Gene Delivery ◽  
Low Molecular Weight ◽  
Ortho Ester ◽  
Ester Linkage ◽  
Acid Labile

Composition of low molecular weight impurities in dimethylmethylpheylsiloxane rubbers with terminal hydroxyl groups

2020 ◽  
Vol 86 (11) ◽  
pp. 20-27
Author(s):  
A. M. Filippov ◽  
N. Yu. Semenkova ◽  
S. M. Gorelov ◽  
T. I. Shulyatieva ◽  
P. A. Storozhenko
Keyword(s):  
Molecular Weight ◽  
Low Molecular Weight ◽  
Hydroxyl Groups

The Chemistry of Phenol-Formaldehyde Resin Vulcanization of EPDM: Part I. Evidence for Methylene Crosslinks

1995 ◽  
Vol 68 (5) ◽  
pp. 717-727 ◽  
Author(s):  
Martin van Duin ◽  
Aniko Souphanthong
Keyword(s):  
Molecular Weight ◽  
Phenol Formaldehyde ◽  
Polymer System ◽  
Phenol Formaldehyde Resin ◽  
Formaldehyde Resin ◽  
Low Molecular Weight ◽  
Hydroxyl Groups ◽  
Reaction Products ◽  
Cure Reaction ◽  
Weight Model

Abstract The application of phenol-formaldehyde resins as crosslinking agents is increasing in importance due to the good high temperature properties of the corresponding vulcanizate and the use in thermoplastic vulcanizates. With respect to the chemistry of phenol-formaldehyde cure (reaction mechanism and structure of crosslink) there are still problems that have to be resolved. The reaction products of the phenol-formaldehyde resin curing of EPDM, contain 2-ethylidene norbornene (ENB) as the third monomer, have been studied. Since such an investigation is rather difficult to perform for the polymer system, a low molecular weight model for EPDM was used: 2-ethylidene norbornane (ENBH). Reaction of ENBH and a resole results in scission of the dimethylene ether bridges, i.e. in degradation of the resole into mono-, bis- and terisooctylphenol units. These are consequently converted into products, consisting of two ENBH molecules linked by mono-, bis- and terisooctylphenol units. The solid resole seems to be a technological solution for storing phenol in combination with formaldehyde. These results support the use of 2-hydroxymethylphenol (HMP) as a low molecular weight model for the resole. At low temperatures and/or short reaction times HMP oligomers (= resoles) and HMP oligomers linked to one ENBH molecule are formed, which are converted into ENBH/HMP (1:1) condensation products. The reaction products of ENBH with both the resole and HMP are shown to contain methylene linked structures, as demonstrated by the formation of monisooctylphenol crosslinks and the presence of residual unsaturation and hydroxyl groups, besides chroman linked structures. This is the first experimental evidence that during phenol-formaldehyde resin cure of rubber, formation of methylene bridges occurs.

Zinc ion coordination significantly improved the transfection efficiency of low molecular weight polyethylenimine

2019 ◽  
Vol 7 (4) ◽  
pp. 1716-1728 ◽  
Author(s):  
Huapan Fang ◽  
Lin Lin ◽  
Jie Chen ◽  
Jiayan Wu ◽  
Huayu Tian ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Gene Delivery ◽  
Delivery System ◽  
Transfection Efficiency ◽  
Zinc Ion ◽  
Low Molecular Weight ◽  
Gene Delivery System ◽  
System P

A zinc ion coordination-contained polycationic gene delivery system.

scholarly journals Binding Affinity, Cellular Uptake, and Subsequent Intracellular Trafficking of the Nano-Gene Vector P123-PEI-R13

2016 ◽  
Vol 2016 ◽  
pp. 1-8
Author(s):  
Yaguang Zhang ◽  
Hongmei Shu ◽  
Jing Hu ◽  
Min Zhang ◽  
Junweng Wu ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Cellular Uptake ◽  
Intracellular Trafficking ◽  
Transfection Efficiency ◽  
Cross Linking ◽  
Low Molecular Weight ◽  
Gene Vector ◽  
Dna Complexes ◽  
Dynamic Source

A nano-gene vector PEI-P123-R13 was synthesized by cross-linking low molecular weight PEI with P123 and further coupling bifunctional peptide R13 to the polymer for targeting tumor and increasing cellular uptake. The binding assessment of R13 toαvβ3 positive cells was performed by HRP labeling. The internalization pathways of P123-PEI-R13/DNA complexes were investigated based on the effect of specific endocytic inhibitors on transfection efficiency. The mechanism of intracellular trafficking was investigated based on the effect of endosome-lysosome acidification inhibitors, cytoskeleton, and dynein inhibitors on transfection efficiency. The results indicated that the bifunctional peptide R13 had the ability of binding toαvβ3 positive cellsin vitro. The modification of P123-PEI-R13 with R13 made it display new property of internalization. P123-PEI-R13/DNA complexes were conducted simultaneously via clathrin-mediated endocytosis, caveolin-mediated endocytosis, macropinocytosis, and possible energy-independent route. After internalization, P123-PEI-R13/DNA complexes could escape from the endosome-lysosome system because of its acidification and further took microtubule as the track and dynein as the dynamic source to be transported toward the microtubule (+) end, to wit nucleus, under the action of microfilament, and with the aid of intermediate filament.

Diol glycidyl ether-bridged low molecular weight PEI as potential gene delivery vehicles

2015 ◽  
Vol 3 (13) ◽  
pp. 2660-2670 ◽  
Author(s):  
Qian Guo ◽  
Yan-Hong Liu ◽  
Miao-Miao Xun ◽  
Ji Zhang ◽  
Zheng Huang ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Gene Delivery ◽  
Ring Opening ◽  
Transfection Efficiency ◽  
Glycidyl Ether ◽  
Ring Opening Polymerization ◽  
Low Molecular Weight ◽  
Delivery Vehicles ◽  
Gene Delivery Vehicles

PEI 600-based polymers were synthesized via ring-opening polymerization and exhibited much better transfection efficiency and biocompatibility than PEI 25 kDa.

scholarly journals Bioorganic studies on the venom from duckbill platypus

2012 ◽  
Vol 84 (6) ◽  
pp. 1317-1328 ◽  
Author(s):  
Masaki Kita
Keyword(s):  
Molecular Weight ◽  
Guinea Pig ◽  
Structure And Function ◽  
Low Molecular Weight ◽  
Tissue Kallikrein ◽  
Guinea Pig Ileum ◽  
Porcine Pancreas ◽  
Human Neuroblastoma ◽  
Ornithorhynchus Anatinus ◽  
And Function

Venomous mammals are rare, and only a few species in the orders Insectivora and Monotremata produce toxic venom. Among them, the duckbill platypus (Ornithorhynchus anatinus) is one of the two venomous Australian mammals. The adult male platypus carries a spur on each hind leg, which it uses to inject competitors with poison. However, the structure and function of the poison’s active compounds are still imcompletely characterized. We found that crude platypus venom produced potent Ca2+influx in human neuroblastoma IMR-32 cells. Guided by this assay, we identified 11 unique peptides, including peptide H–His–Asp–His–Pro–Asn–Pro–Arg–OH, which coincided with the N-terminal domain residues ofOrnithorhynchusvenom C-type natriuretic peptide (OvCNP). This heptapeptide induced a significant increase in [Ca2+]iin IMR-32 cells at 75 μM; had relatively specific affinities for glutamate, histamine, and GABAAreceptors; and facilitated neurogenic twitching in guinea pig ileum specimens at 30 μM. We also established that its proteinous venom fraction strongly hydrolyzed Pro–Phe–Arg–MCA and cleaved a human low-molecular-weight kininogen (LK), similar to porcine pancreas kallikrein. These results strongly indicated that platypus venom contains tissue kallikrein-like protease(s), and its proteolytic activity might synergistically contribute to toxicity through the specific cleavage of other venom constituents.

scholarly journals Fructose 2,6-bisphosphate, the probably structure of the glucose- and glucagon-sensitive stimulator of phosphofructokinase

1980 ◽  
Vol 192 (3) ◽  
pp. 897-901 ◽  
Author(s):  
E Van Schaftingen ◽  
L Hue ◽  
H G Hers
Keyword(s):  
Molecular Weight ◽  
Rat Liver ◽  
Reducing Power ◽  
Organic Phosphate ◽  
Low Molecular Weight ◽  
Acid Labile

The low-molecular-weight stimulator of phosphofructokinase [Van Schaftingen, Hue & Hers (1980) Biochem. J. 192, 887-895] has been purified from rat liver. It was completely destroyed upon incubation with 0.01 M-HCl for 10 min at 20 degrees C and fructose 6-phosphate and a reducing power equivalent in amount to the acid-labile organic phosphate were formed. It was therefore tentatively identified as fructose 2,6-bisphosphate.

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