To solve the problem of transfection efficiency vs. cytotoxicity and tumor-targeting ability when polyethylenimine (PEI) was used as a nonviral gene delivery vector, new degradable PEI polymers were synthesized via cross-linking low-molecular-weight PEI with Pluronic P123 and then further coupled with a targeting peptide R4 (RGD) and a bifunctional R11 (RGD-NLS), which were termed as P123-PEI-R...

Transgene transfection techniques using cationic polymers such as polyethylenimines (PEIs) and PEI derivatives as gene vectors have shown efficacy, although they also have shortcomings. PEIs have decent DNA-binding capability and good cell internalization performance, but they cannot deliver gene payloads very efficiently to cell nuclei. In this study, three hyperbranched polyglycerol-polyethyl...

Objective(s): Polyethylenimine (PEI) is one of the most widely used polymers in gene delivery. The aim of this study was to modify PEI by replacing some of its primary amines with Brevinin 2R (BR-2R) peptide in order to increase the efficiency of gene delivery.Materials and Methods: Polyethylenimine was modified by BR-2R peptide by two d...

Chemically ordered, self-assembled FePt nanoparticle arrays with high magnetic anisotropy are considered a candidate medium for data storage beyond 1 Tbit/in. We report comprehensive structural and magnetic studies on thin (3 layer) assemblies of polyethylenimine (PEI) and 4 nm Fe58Pt42 nanoparticles using X-ray diffraction, small angle neutron scattering and magnetometry. We show that prior to...

We report a direct method to amplify the exponential growth of multilayers significantly by the alternating deposition of polyethylenimine (PEI) at high pH and poly(acrylic acid) (PAA) at low pH. The alternating pH switches the degree of ionization of the polyelectrolytes in the multilayers, which enhances the diffusion of PEI into and out of the film and hence increases the deposited mass per ...

Polyethylenimine (PEI) has been proposed as a non-viral vector, and has been successfully used to transfer reporter genes into the central nervous system (CNS), kidneys, and lungs of adult mice. Neuropeptide Y (NPY) is a peptide expressed in the hypothalamus and is important in the regulation of body weight. Using PEI combined with stereotactic microinjection, we have successfully transferred c...

Polyethylenimine (PEI), especially PEI 25 kDa, has been widely studied for delivery of nucleic acid drugs both in vitro and in vivo. However, it lacks degradable linkages and is too toxic for therapeutic applications. Hence, low-molecular-weight PEI has been explored as an alternative to PEI 25 kDa. To reduce cytotoxicity and increase transfection efficiency, we designed and synthesized a novel...

Graphene oxide (GO) sheets exhibit superior adsorption capacity for removing organic dye pollutants from an aqueous environment. In this paper, the facile preparation of GO/polyethylenimine (PEI) hydrogels as efficient dye adsorbents has been reported. The GO/PEI hydrogels were achieved through both hydrogen bonding and electrostatic interactions between amine-rich PEI and GO sheets. For both m...

An antibody-directed nonviral vector, polyethylene glycol-grafted polyethylenimine functionalized with superparamagnetic iron oxide nanoparticles and a gastric cancer-associated CD44v6 single-chain variable fragment (scFv(CD44v6),-PEG-g-PEI-SPION), was constructed as a gastric cancer-targeting and magnetic resonance imaging (MRI)-visible nanocarrier for small interfering RNA (siRNA) delivery. B...