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1.
Non-viral gene delivery systems based on cationic polymers have faced limitations related to their relative low gene transfer efficiency, cytotoxicity and system instability in vivo. In this paper, a flexible and pompon-like dendrimer composed of poly (amidoamine) (PAMAM) G4.0 as the inner core and poly (L-glutamic acid) grafted low-molecular-weight polyethylenimine (PLGE) as the surrounding multiple arms was synthesized (MGI dendrimer). The novel MGI dendrimer was designed to combine the merits of size-controlled PAMAM G4.0 and the low toxicity and flexible chains of PLGE. In phosphate-buffered saline dispersions the well-defined DNA/MGI complex above a N/P ratio of 30 showed good stability with particle sizes of approximately 200 nm and a comparatively low polydispersity index. However, the particle size of the DNA/25 kDa polyethylenimine (DNA/PEI 25K) complex was larger than 700 nm under the same salt conditions. The shielding of the compact amino groups at the periphery of flexible PAMAM and biocompatible PLGE chains in MGI resulted in a dramatic decrease of the cytotoxicity compared to native PAMAM G4.0 dendrimer. The in vitro transfection efficiency of DNA/MGI dendrimer complex was higher than that of PAMAM G4.0 dendrimer. Importantly, in serum-containing medium, DNA/MGI complexes at their optimal N/P ratio maintained the same high levels of transfection efficiency as in serum-free medium, while the transfection efficiency of native PAMAM G4.0, PEI 25K and Lipofectamine 2000 were sharply decreased. In vivo gene delivery of pVEGF165/MGI complex into balloon-injured rabbit carotid arteries resulted in significant inhibition of restenosis by increasing VEGF165 expression in local vessels. Therefore, the pompon-like MGI dendrimer may be a promising vector candidate for efficient gene delivery in vivo. 相似文献
2.
Enhancement of gene transfer to cervical cancer cells using transferrin-conjugated liposome 总被引:2,自引:0,他引:2
Transferrin-conjugated cationic liposome (Tf -DDAB liposome) was developed as a targeted gene delivery system by using heterobifunctional cross-linking agent, N-succimidyl-3-(2-pyridyldithio)propionate (SPDP), and gradient metrizamide ultracentrifugation method. Physico-chemical properties of Tf -liposome were determined by scanning/transmission electron microscopy (SEM/TEM) and dynamic laser-light scattering method (DLS) with a mean diameter of 584±15 nm. Gel retardation assay was performed using various DDAB:DNA ratios, and proved that the 6:1 weight ratio formulation gave the most neutralized complex. In vitro transfection was done in human cervical cancer cells, HeLa, and the transfection efficiency of Tf -liposome was found to be fivefold higher than that of unconjugated (plain) DDAB liposome and twofold higher than that of Lipofectin™. In conclusion, a target-oriented Tf -DDAB liposome was made successfully and proved to be very efficient in DNA delivery into the cervical cancer cells in culture. 相似文献
3.
Anionic Lipid,pH‐Sensitive Liposome‐Gold Nanoparticle Hybrids for Gene Delivery – Quantitative Research of the Mechanism
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Baoji Du Li Tian Xiaoxiao Gu Dan Li Erkang Wang Jin Wang 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(19):2333-2340
Gene therapy is a potential method for treating a large range of diseases. Gene vectors are widely used in gene therapy for promoting the gene delivery efficiency to the target cells. Here, gold nanoparticles (AuNPs) coated with dimethyldioctadecylammonium bromide (DODAB)/dioleoylphosphatidylethanolamine (DOPE) are synthesized using a facile method for a new gene vector (DODAB/DOPE‐AuNPs), which possess 3‐ and 1.5‐fold higher transfection efficiency than those of DODAB‐AuNPs and a commercial transfection agent, respectively. Meanwhile, it is nontoxic with concentrations required for effective gene delivery. Imaging and quantification studies of cellular uptake reveal that DOPE increases gene copies in cells, which may be attributed to the smaller size of AuNPs/DNA complexes. The dissociation efficiency of DNA from the endocytic pathway is quantified by incubating with different buffers and investigated directly in the cells. The results suggest that DOPE increases the internalization of AuNPs/DNA complexes and promotes DNA release from early endosomes for the vector is sensitive to the anionic lipid membrane and the decreasing pH along the endocytic pathway. The new vector contains the potential to be the new alternative as gene delivery vector for biomedical applications. 相似文献
4.
《Drug development and industrial pharmacy》2013,39(8):1023-1031
ABSTRACTTransferrin-conjugated cationic liposome (Tf -DDAB liposome) was developed as a targeted gene delivery system by using heterobifunctional cross-linking agent, N-succimidyl-3-(2-pyridyldithio)propionate (SPDP), and gradient metrizamide ultracentrifugation method. Physico-chemical properties of Tf -liposome were determined by scanning/transmission electron microscopy (SEM/TEM) and dynamic laser-light scattering method (DLS) with a mean diameter of 584±15 nm. Gel retardation assay was performed using various DDAB:DNA ratios, and proved that the 6:1 weight ratio formulation gave the most neutralized complex. In vitro transfection was done in human cervical cancer cells, HeLa, and the transfection efficiency of Tf -liposome was found to be fivefold higher than that of unconjugated (plain) DDAB liposome and twofold higher than that of Lipofectin?. In conclusion, a target-oriented Tf -DDAB liposome was made successfully and proved to be very efficient in DNA delivery into the cervical cancer cells in culture. 相似文献
5.
《Journal of Experimental Nanoscience》2013,8(2):235-248
Gene transfer to humans requires carriers for the plasmid DNA, which can efficiently and safely carry the gene into the nucleus of the desired cells. The purpose of the present study was to design dendrosomes as a novel, non-viral, vesicular, gene delivery vector and to carry out a comparative study of the relative transfection efficiencies of dendrosomes with standard non-viral, gene delivery vectors. Fourth-generation PAMAM dendrimers were synthesized by double the Michael addition reaction and extensively characterized. The dendrimer–DNA complex was prepared and was confirmed by CD spectroscopy. The dendrosomes were prepared by the reverse phase evaporation method and the entrapment efficiency of the dendrosomal formulation was estimated. In vitro toxicity of the formulation was evaluated by hemolytic toxicity and cytotoxicity studies. Transfection efficiency of the dendrosomal formulations was compared to standard non-viral gene delivery vectors in HEK-293 cell. The results of hemolytic toxicity cytotoxicity studies demonstrated that the dendrosomes possess negligible toxicity as compared to the other formulations and are suitable for in vivo administration. The results of transfection of HEK-293 cell with PGL2 showed that the dendrosomal formulation DF3 possesses superior transfection efficiency against other delivery systems under study. Dendrosomes possess tremendous potential as a novel non-viral and non-toxic gene delivery vector. 相似文献
6.
Fe3O4 nanoparticles (NPs) are widely used in the construction of drug and gene delivery vectors because of their particular physicochemical properties. Surface modification can not only reduce the cytotoxicity of Fe3O4, but also further improve the biocompatibility and delivery efficiency. In this work, firstly, polydopamine (PDA)-coated Fe3O4 NPs (named Fe3O4@PDA) were prepared by using the self-polymerization characteristics of dopamine in alkaline environment. Then, polyamidoamine (PAMAM) was modified by the Michael addition reaction to prepare water-soluble core‒shell magnetic NPs of Fe3O4@PDA@PAMAM, and its potential as gene vector was further evaluated. The results revealed that Fe3O4@PDA@PAMAM had the ability to condense and protect DNA, and showed lower cytotoxicity, higher cell uptake and transfection efficiency than those of PAMAM. It has the potential to become a magnetic targeted gene vector for further study. 相似文献
7.
The clinical success of gene therapy for lung cancer is not only dependent on efficient gene carriers but also on a suitable delivery route. A pulmonary delivery route can directly deliver gene vectors to the lung which is more efficient than a systemic delivery route. For gene carriers, cationic liposomes have recently emerged as leading non-viral vectors in worldwide gene therapy clinical trials. However, cytotoxic effects or apoptosis are often observed which is mostly dependent on the cationic lipid used. Therefore, an efficient and safe cationic lipid, 6-lauroxyhexyl lysinate (LHLN), previously synthesized by our group was first used to prepare cationic liposomes. Physicochemical and biological properties of LHLN-liposomes were investigated. LHLN-liposome/DNA complexes showed positive surface charge, spherical morphology, a relatively narrow particle size distribution and strong DNA binding capability. Compared with Lipofectamine2000, the new cationic liposome formulation using LHLN exhibited not only lower cytotoxicity (P < 0.05) but also similar transfection efficiency in A549 and HepG2 lung cancer cells for in vitro tests. When administered by intratracheal instillation into rat lungs for in vivo evaluation, LHLN-liposome/DNA complexes exhibited higher pulmonary gene transfection efficiency than Lipofectamine2000/DNA complexes (P < 0.05). These results suggested that LHLN-liposomes may have great potential for efficient pulmonary gene delivery. 相似文献
8.
Luo X Feng M Pan S Wen Y Zhang W Wu C 《Journal of materials science. Materials in medicine》2012,23(7):1685-1695
Polyethylenimine (PEI) is an efficient cationic polymer for gene delivery, but defective in biocompatibility. In this study, we developed two different strategies to shield the positively charged PEI/DNA complexes: PEGylation and lipid coating. The physicochemical properties, cytotoxicity and transfection efficiency of the two gene delivery systems were investigated. Both PEGylation and lipid coating succeeded in reducing the zeta-potential of the complexes. Lipid-coated PEI/DNA complexes (LPD complexes) and PEI/DNA complexes exhibited similar cytotoxicity, whereas PEG-PEI/DNA complexes showed lower cytotoxicity, especially at high N/P ratios. LPD complexes were less efficient in transfection compared to PEG-PEI/DNA complexes. The transfection efficiency was influenced remarkably by cytotoxicity and surface charge of the complexes. Intracellular processes studies revealed that endosomal release might be one of the rate-limiting steps in cell transfection with PEI as a gene delivery carrier. 相似文献
9.
《Journal of Experimental Nanoscience》2013,8(2):165-176
The structural and physicochemical properties of novel cationic lipid-based DNA complexes have been investigated for the purpose of designing micro/nano-scale self-assembling delivery systems for cutaneous gene therapy. DNA/gemini surfactant (spacer n?=?3–16; chain m?=?12 or 16) complexes (1?:?10 charge ratio), with or without dioleoylphosphatidyl-ethanolamine (DOPE), designed for cellular transfection, were generally in the range of 100–200?nm as demonstrated by atomic force microscopy and particle size analysis. Small-angle X-ray scattering measurements indicated that the DNA/gemini complexes lacked long-range order, whereas DNA/gemini/DOPE complexes exhibited lamellar and polymorphic phases other than hexagonal. Correlation studies using transfection efficiency data in PAM 212 keratinocytes and in vitro skin absorption indicated that formulations containing gemini surfactants having the ability to induce structures other than lamellar in the resulting complexes, generally exhibited greater transfection activity and cutaneous absorption. 相似文献
10.
We report small angle X-ray and neutron scattering measurements that reveal that mixtures of the redox-active lipid bis(11-ferrocenylundecyl)dimethylammonium bromide (BFDMA) and dioleoylphosphatidylethanolamine (DOPE) spontaneously form lipoplexes with DNA that exhibit inverse hexagonal nanostructure (H(II) (c)). In contrast to lipoplexes of DNA and BFDMA only, which exhibit a multilamellar nanostructure (L(α) (c)) and limited ability to transfect cells in the presence of serum proteins, we measured lipoplexes of BFDMA and DOPE with the H(II) (c) nanostructure to survive incubation in serum and to expand significantly the range of media compositions (e.g., up to 80% serum) over which BFDMA can be used to transfect cells with high efficiency. Importantly, we also measured the oxidation state of the ferrocene within the BFDMA/DNA lipoplexes to have a substantial influence on the transfection efficiency of the lipoplexes in media containing serum. Specifically, whereas lipoplexes of reduced BFDMA and DOPE transfect cells with high efficiency, lipoplexes of oxidized BFDMA and DNA lead to low levels of transfection. Complementary measurements using SAXS reveal that the low transfection efficiency of the lipoplexes of oxidized BFDMA and DOPE correlates with the presence of weak Bragg peaks and thus low levels of H(II) (c) nanostructure in solution. Overall, these results provide support for our hypothesis that DOPE-induced formation of the H(II) (c) nanostructure of the BFDMA-containing lipoplexes underlies the high cell transfection efficiency measured in the presence of serum, and that the oxidation state of BFDMA within lipoplexes with DOPE substantially regulates the formation of the H(II) (c) nanostructure and thus the ability of the lipoplexes to transfect cells with DNA. More generally, the results presented in this paper suggest that lipoplexes formed from BFDMA and DOPE may offer the basis of approaches that permit active and external control of transfection of cells in the presence of high (physiologically relevant) levels of serum. 相似文献
11.
D. Ang C.Y. Tay L.P. Tan P.R. Preiser R.V. Ramanujan 《Materials science & engineering. C, Materials for biological applications》2011,31(7):1445-1457
In the magnetically enhanced gene delivery technique, DNA complexed with polymer coated aggregated magnetic nanoparticles (AMNPs) is used for effecting transfection. The aim of this study is to examine the relationship between transfection efficiency and the physical characteristics of the polymer coated AMNPs. In vitro studies of transfection efficiency in COS-7 cells were carried out using pEGFP-N1 and pMIR-REPORT complexed polyethylenimine (PEI) coated iron oxide magnetic nanoparticles. PEI coated AMNPs (PEI-AMNPs) with average individual particle diameters in the range of 8 nm to 30 nm were studied and characterized by transmission electron microscopy, vibrating sample magnetometry, X-ray diffractometry, thermal gravimetric analysis and photon correlation spectroscopy methods. PEI-A8MNP and PEI-A30MNP yielded higher transfection efficiency compared to commercial polyMAG particles as well as PEI of equivalent molar ratio of nitrogen/phosphorous (N/P ratio). The transfection efficiency was related to the physical characteristics of the PEI-AMNPs and its complexes: transfection efficiency was strongly positively correlated with saturation magnetization (Ms) and susceptibility (χ), strongly negatively correlated with N/P ratio, moderately positively correlated to zeta potential and moderately negatively correlated to hydrodynamic diameter of the complex. PEI-A8MNP and PEI-A30MNP possessing higher Ms, χ, lower N/P ratio and smaller complex size exhibited higher transfection efficiency compared to PEI-A16MNP which have weaker magnetic properties, higher N/P ratio and larger complex size. We have demonstrated that optimization of the physical properties of PEI-AMNPs is needed to maximize transfection efficiency. 相似文献
12.
Kneuer C Ehrhardt C Bakowsky H Kumar MN Oberle V Lehr CM Hoekstra D Bakowsky U 《Journal of nanoscience and nanotechnology》2006,6(9-10):2776-2782
Various polycationic vehicles have been developed to facilitate the transfer of foreign DNA into mammalian cells. Structure-activity studies suggested that biophysical properties, such as size, charge, and morphology of the resulting DNA complexes determine transfection efficiency within one class of vector. To investigate the general validity of these criteria, we studied the efficacy of a variety of DNA delivery vehicles including liposomes (DOTAP, SAINT2) with and without helper lipid (DOPE), the polymer polyethyleneimine (PEI), and cationic nanoparticles (Si26H, PLGA/chitosan) in a comparative manner. Sizes of the DNA complexes varied between 100 and 500 nm for PEI polyplexes and DOTAP/DOPE lipoplexes, respectively. The zeta potential was positive for PEI, Si26H, and DOTAP based complexes, while it was neutral for SAINT2-DNA complexes and negative for PLGA/chitosan-DNA complexes. The latter finding was elucidated by AFM, showing a layer of DNA adsorbed onto the nanoparticles. Transfection activity was negligible for PLGA/chitosan nanospheres, moderate for Si26H nanospheres and high for all other complexes, PEI being the most active carrier. The liposomal preparations were of low (DOTAP) or moderate (SAINT2) stability in serum, resulting in a pronounced reduction of gene expression, which was partially restored by the addition of chloroquine. In conclusion, transfection efficiency (i) seems to require a positive or neutral zeta potential, (ii) is depending on size, e.g., is higher for smaller particles, and (iii) requires a vector that is stable in serum. 相似文献
13.
14.
Kim JH Kim YK Arash MT Hong SH Lee JH Kang BN Bang YB Cho CS Yu DY Jiang HL Cho MH 《Journal of nanoscience and nanotechnology》2012,12(7):5178-5184
Polyethyleneimine (PEI) has been described as a highly efficient gene carrier due to its efficient proton sponge effect within endosomes. However, many studies have demonstrated that PEI is toxic and associated with a lack of cell specificity despite high transfection efficiency. In order to minimize the toxicity of PEI, we prepared chitosan-graft-spermine (CHI-g-SPE) in a previous study. CHI-g-SPE showed low toxicity and high transfection efficiency. However, this compound also had limited target cell specificity. In the present study, we synthesized galactosylated CHI-g-SPE (GCS) because this modified GCS could be delivered specifically into the liver due to hepatocyte-specific galactose receptors. The DNA-binding properties of GCS at various copolymer/DNA weight ratios were evaluated by a gel retardation assay. The GCS copolymer exhibited significant DNA-binding ability and efficiently protected DNA from nuclease attack. Using energy-filtered transmission electron microscopy (EF-TEM), we observed dense spherical, nano-sized GCS/DNA complexes with a homogenous distribution. Most importantly, GCS was associated with remarkably low cytotoxicity compared to PEI in HepG2, HeLa, and A549 cells. Moreover, GCS carriers specifically delivered the gene-of-interest into hepatocytes in vitro as well as in vivo. Our results suggest that the novel GCS described here is a safe and highly efficient carrier for hepatocyte-targeted gene delivery. 相似文献
15.
Externally stimuli‐triggered spatially and temporally controlled gene delivery can play a pivotal role in achieving targeted gene delivery with maximized therapeutic efficacy. In this study, a photothermally controlled gene delivery carrier is developed by conjugating low molecular‐weight branched polyethylenimine (BPEI) and reduced graphene oxide (rGO) via a hydrophilic polyethylene glycol (PEG) spacer. This PEG–BPEI–rGO nanocomposite forms a stable nano‐sized complex with plasmid DNA (pDNA), as confirmed by physicochemical studies. For the in vitro gene transfection study, PEG–BPEI–rGO shows a higher gene transfection efficiency without observable cytotoxicity compared to unmodified controls in PC‐3 and NIH/3T3 cells. Moreover, the PEG–BPEI–rGO nanocomposite demonstrates an enhanced gene transfection efficiency upon NIR irradiation, which is attributed to accelerated endosomal escape of polyplexes augmented by locally induced heat. The endosomal escaping effect of the nanocomposite is investigated using Bafilomycin A1, a proton sponge effect inhibitor. The developed photothermally controlled gene carrier has the potential for spatial and temporal site‐specific gene delivery. 相似文献
16.
Yangbo Zhou Zhaomin Tang Chunli Shi Shuai Shi Zhiyong Qian Shaobing Zhou 《Journal of materials science. Materials in medicine》2012,23(11):2697-2708
Polyethylenimine (PEI) functionalized magnetic nanoparticles were synthesized as a potential non-viral vector for gene delivery. The nanoparticles could provide the magnetic-targeting, and the cationic polymer PEI could condense DNA and avoid in vitro barriers. The magnetic nanoparticles were characterized by Fourier transform infrared spectroscopy, X-ray powder diffraction, dynamic light scattering measurements, transmission electron microscopy, vibrating sample magnetometer and atomic force microscopy. Agarose gel electrophoresis was used to asses DNA binding and perform a DNase I protection assay. The Alamar blue assay was used to evaluate negative effects on the metabolic activity of cells incubated with PEI modified magnetic nanoparticles and their complexes with DNA both in the presence or absence of an external magnetic field. Flow cytometry and fluorescent microscopy were also performed to investigate the transfection efficiency of the DNA-loaded magnetic nanoparticles in A549 and B16-F10 tumor cells with (+M) or without (?M) the magnetic field. The in vitro transfection efficiency of magnetic nanoparticles was improved obviously in a permanent magnetic field. Therefore, the magnetic nanoparticles show considerable potential as nanocarriers for gene delivery. 相似文献
17.
Alireza Nouri Rita Castro Visvaldas Kairys José L. Santos Jo?o Rodrigues Yulin Li Helena Tomás 《Journal of materials science. Materials in medicine》2012,23(12):2967-2980
In the present study, the effect of N,N-dimethylaminoethyl methacrylate (DMAEMA) conjugation onto branched poly(ethylenimine) (PEI) with different grafting degree was examined for gene delivery applications. The DMAEMA-grafted-PEI conjugates were characterized and complexed with plasmid DNA (pDNA) at various concentrations, and the physicochemical properties, cell viability, and in vitro transfection efficiency of the complexes were evaluated in HEK 293T cells. Computational techniques were used to analyze the interaction energies and possible binding modes between DNA and conjugates at different grafting degrees. The cytotoxicity analysis and in vitro transfection efficiency of the conjugate/pDNA complexes exhibited a beneficial effect of DMAEMA conjugation when compared to PEI alone. The computational results revealed that the DNA/vector interaction energy decreases with increasing grafting degree, which can be associated to an enhanced release of the pDNA from the carrier once inside cells. The results indicate the significance of DMAEMA conjugation onto PEI as a promising approach for gene delivery applications. 相似文献
18.
A. Hanifi M. H. Fathi H. Mir Mohammad Sadeghi 《Journal of materials science. Materials in medicine》2010,21(9):2601-2609
Gene therapy has been considered a strategy for delivery of therapeutic nucleic acids to a specific site. Calcium phosphates
are one gene delivery vector group of interest. However, low transfection efficiency has limited the use of calcium phosphate
in gene delivery applications. Present work aims at studying the fabrication of strontium substituted calcium phosphate nanoparticles
with improved gene delivery related properties. Strontium substituted calcium phosphate was prepared using a simple sol gel
method. X-ray diffraction analysis, Fourier transform infrared spectroscopy, transmission electron microscopy, specific surface
area analysis, zeta potential measurement and ion release evaluation were used to characterize the samples. This characterization
showed strontium and carbonate co-substituted calcium phosphate which resulted in nano size particles with low crystallinity,
high specific surface area, positive surface charge, and a high dissolution rate. These improved properties could increase
the DNA concentration on the vector as well as the endosomal escape of the complex that leads to higher transfection efficiency
of this novel gene delivery vector. 相似文献
19.
Yilong Cheng Hua Wei James‐Kevin Y. Tan David J. Peeler Don O. Maris Drew L. Sellers Philip J. Horner Suzie H. Pun 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(20):2750-2758
The architecture of polycations plays an important role in both gene transfection efficiency and cytotoxicity. In this work, a new polymer, sunflower poly(2‐dimethyl amino)ethyl methacrylate) (pDMAEMA), is prepared by atom transfer radical polymerization and employed as nucleic acid carriers compared to linear pDMAEMA homopolymer and comb pDMAEMA. The sunflower pDMAEMAs show higher IC50, greater buffering capacity, and stronger binding capacity toward plasmid DNA than their linear and comb counterparts. In vitro transfection studies demonstrate that sunflower pDMAEMAs exhibit high transfection efficiency as well as relatively low cytotoxicity in complete growth medium. In vivo gene delivery by intraventricular injection to the brain shows that sunflower polymer delivers plasmid DNA more effectively than comb polymer. This study provides a new insight into the relationship between polymeric architecture and gene delivery capability, and as well as a useful means to design potent vectors for successful gene delivery. 相似文献
20.
Self assembly of DNA nanoparticles with polycations for the delivery of genetic materials into cells
Increasing attention has been paid to technology used for the delivery of genetic materials into cells for gene therapy and the generation of genetically engineered cells. So far, viral vectors have been mainly used because of their inherently high transfection efficiency of gene. However, there are some problems to be resolved for the clinical applications, such as the pathogenicity and immunogenicity of viral vectors themselves. Therefore, many research trials with non-viral vectors have been performed to enhance their efficiency to a level comparable to the viral vector. Two directions of these trials exist: Material improvement of non-viral vectors and their combination with various external physical stimuli. In this study gelatin was selected as a non-viral carrier for DNA. To give a positive charge to gelatin, different extents introduction of ethylenediamine (Ed), spermidine (Sd), and spermine (Sm) were reacted with gelatin in the presence of a water-soluble carbodiimide. When positively charged gelatin derivatives (Ed, Sd, and Sm) were mixed with negatively charged DNA, a self assembly of DNA nanoparticle (complex) was formed within few minutes through electrostatic interaction. Irrespective of the type of gelatin derivatives, the apparent molecular size of DNA was reduced by increasing the gelatin/DNA mixing ratio to attain a saturated value of about 150 nm. The condensed gelatin/DNA complexes showed the zeta potential of 10-15 mV. The amount of DNA internalized into the cells was significantly increased by the complexation with every gelatin derivative. The cells incubated with the gelatin/DNA complexes exhibited significantly stronger luciferase activities than naked plasmid DNA. This study clearly demonstrates and self-assembled DNA complexes has potential as a gene delivery vechile and are stable to transfer genetic materials to cells. 相似文献