Synthesis and characterization of chitosan-g-poly(ethylene glycol)-folate as a non-viral carrier for tumor-targeted gene delivery (original) (raw)

A pH-sensitive gene delivery system based on folic acid-PEG-chitosan – PAMAM-plasmid DNA complexes for cancer cell targeting

Biomaterials, 2013

In this study, pH-sensitive biomaterials coated polymer/DNA nanocomplexes containing a high mobility group box 1 (HMGB1) were developed as an efficient non-viral gene delivery system. HMGB1 is a family of endogenous molecules that contains nuclear locating sequences (NSL). Polyethylene glycol tethered carboxylated chitosan modified with folic acid (FA-PEG-CCTS) was synthesized and its buffering capacity was determined by acidebase titration. A pH-sensitive coreeshell system FA-PEG-CCTS/PAMAM/ HMGB1/pDNA nanocomplexes (FPCPHDs), was prepared and characterized. Electrophoresis showed that FPCPHDs were resistant to heparin replacement and DNase I digestion. FPCPHDs exhibited only minor toxic effects on HepG2 and KB cells. The results of both luciferase activity assay and RFP fluorescence intensity analysis showed that FPCPHDs enhanced gene transfection and expression in KB cells. Moreover, gene transfection and expression in KB cells were inhibited by free folic acid. Intracellular trafficking of FPCPHDs in KB cells showed that FPCPHDs could rapidly escape from endo-lysosomes and become exclusively located in the nucleus at 3 h post transfection. In addition, FPCPHDs exhibited increased red fluorescence protein (RFP) expression at the tumor site of S180 xenograft nude mice. All results suggest that FPCPHDs is an efficient approach to improve the transfection and expression efficiency in most FR-positive cancer cells.

Characterization of folate-chitosan-DNA nanoparticles for gene therapy

Biomaterials, 2006

Gene therapy using polymers such as chitosan shows good biocompatibility, but low transfection efficiency. The mechanism of folic acid (FA) uptake by cells to promote targeting and internalization could improve transfection rates. The objective of this study was to synthesize and characterize FA-chitosan-DNA nanoparticles and evaluate their cytotoxicity in vitro. Chitosan-DNA and FA-Chitosan-DNA nanoparticles were prepared using reductive amidation and a complex coacervation process. The effect of charge ratio on the properties of these nanoparticles was monitored by laser scattering. DNA inclusion and integrity was evaluated by gel electrophoresis. Cell viability was illustrated with the MTT assay. Charge ratio (N/P) controlled the nanoparticles size and their zeta potential. Nanoparticles presented a mean size of 118 nm and 80% cellular viability compared to 30% cell viability using LipofectAMINE2000 controls. Gel electrophoresis showed intact DNA within the carriers.

Efficient Nonviral Gene Therapy Using Folate-Targeted Chitosan-DNA Nanoparticles In Vitro

ISRN Pharmaceutics, 2012

Nonviral cationic polymers like chitosan can be combined with DNA to protect it from degradation. The chitosan is a biocompatible, biodegradable, nontoxic, and cheap polycationic polymer with low immunogenicity. The objective of this study was to synthesize and then assess different chitosan-DNA nanoparticles and to select the best ones for selectivein vitrotransfection in human epidermoid carcinoma (KB) cell lines. It revealed that different combinations of molecular weight, the presence or absence of folic acid ligand, and different plasmid DNA sizes can lead to nanoparticles with various diameters and diverse transfection efficiencies. The intracellular trafficking, nuclear uptake, and localization are also studied by confocal microscopy, which confirmed that DNA was delivered to cell nuclei to be expressed.

A novel PEGylation of chitosan nanoparticles for gene delivery

Biotechnology and Applied Biochemistry, 2007

CS (chitosan) has emerged as a promising non-viral vector for gene delivery because of its ability to form complexes with pDNA (plasmid DNA) and enhance its transport across cellular membranes through endocytosis. Complexes of CS and pDNA may improve transfection efficiency; however, they are not capable of sustained DNA release and prolonging gene transfer. In order to achieve prolonged delivery of CS-DNA complexes, we prepared CS NP (nanoparticle) and CS-DNA complexes. α-Methoxy-ω-succinimidylpoly(ethylene glycol) was then conjugated to the surface of CS-DNA complexes using an active ester scheme; finally, the potential of PEGylation [poly(ethylene glycol)ylation] of CS NP as a non-viral gene-delivery vector to transfer exogenous genes in vitro and in vivo were examined. Electrophoretic analysis suggested that CS NPs could protect the DNA from nuclease degradation. The pDNA carried by CS NPs could enter and be expressed in HepG2 cells. However, the transfection efficiency was very low and the highest dose of DNA transferred was 1.6 µg. The transfection activities of CS-DNA-PEG were preserved and a higher dose (2.4 µg) of pDNA was transferred. This indicated that the transfection efficiency of the PEGylated complexes had been improved. In vivo experiments also showed that CS-DNA-PEG complexes mediated higher gene expression in tissues than did CS-DNA complexes, and that gene expression in tumours induced by CS-DNA-PEG complexes was the highest of all. These results suggested that PEGylation of CS-DNA complexes improves non-viral gene delivery in vitro or in vivo and has the potential to deliver therapeutic genes directly into hepatoma tissues.

Folic Acid Decorated Chitosan Nanoparticles and its Derivatives for the Delivery of Drugs and Genes to Cancer Cells

Current Science, 2017

Nanotechnology offers a number of nanoscale implements for medicine. Among these, nanoparticles are revolutionizing the field of drug and gene delivery. Chitosan is a natural polymer which provides a profitable tool to an innovative delivery system due to its inherent physicochemical and biological characteristics. Chitosan nanoparticles are promising drug and gene delivery carriers because of small size, better stability, low toxicity, inexpensiveness, simplicity, easy fabrication and versatile means of administration. Chitosan can also be easily modified chemically due to the presence of reactive functional hydroxide and amine groups. Folic acid is commonly engaged as a ligand, for targeting cancer cells, as its receptor, that transports folic acid into the cells through endocytosis and is over-expressed on the surface of several human epithelial cancer cells. Integrating folic acid into chitosan-based drug delivery inventions directs the systems with a well-organized targeting ability. The present review outlines several illustrations of this versatile system based on folate decorated chitosan, which have shown potential as auspicious delivery systems published over the past few years. In addition, it is probable to formulate chitosan nanocarriers that exhibit manifold usage beyond targeted delivery, such as nanotheranostics and cancer stem cell therapy.

Chitosan-DNA nanoparticles as gene carriers: synthesis, characterization and transfection efficiency

Journal of Controlled Release, 2001

Chitosan-DNA nanoparticles were prepared using a complex coacervation process. The important parameters for the nanoparticle synthesis were investigated, including the concentrations of DNA, chitosan and sodium sulfate, temperature of the solutions, pH of the buffer, and molecular weights of chitosan and DNA. At an amino group to phosphate group ratio (N / P ratio) between 3 and 8 and a chitosan concentration of 100 mg / ml, the size of particles was optimized to |100-250 nm with a narrow distribution, with a composition of 35.6 and 64.4% by weight for DNA and chitosan, respectively. The surface charge of these particles was slightly positive with a zeta potential of 112 to 118 mV at pH lower than 6.0, and became nearly neutral at pH 7.2. The chitosan-DNA nanoparticles could partially protect the encapsulated plasmid DNA from nuclease degradation as shown by electrophoretic mobility analysis. The transfection efficiency of chitosan-DNA nanoparticles was cell-type dependent. Typically, it was three to four orders of magnitude, in relative light units, higher than background level in HEK293 cells, and two to ten times lower than that achieved by LipofectAMINEE-DNA complexes. The presence of 10% fetal bovine serum did not interfere with their transfection ability. Chloroquine could be co-encapsulated in the nanoparticles at 5.2%, but with negligible enhancement effect despite the fact that chitosan only showed limited buffering capacity compared with PEI. The present study also developed three different schemes to conjugate transferrin or KNOB protein to the nanoparticle surface. The transferrin conjugation only yielded a maximum of four-fold increase in their transfection efficiency in HEK293 cells and HeLa cells, whereas KNOB conjugated nanoparticles could improve gene expression level in HeLa cells by 130-fold. Conjugation of PEG on the nanoparticles allowed lyophilization without aggregation, and without loss of bioactivity for at least 1 month in storage. The clearance of the PEGylated nanoparticles in mice following intravenous administration was slower than unmodified nanoparticles at 15 min, and with higher depositions in kidney and liver. However, no difference was observed at the 1-h time point.

Effects of molecular weight and pyridinium moiety on water-soluble chitosan derivatives for mediated gene delivery

Carbohydrate Polymers, 2013

The aim of this study is to investigate the effects of molecular weight, the pyridinium/trimethyl ammonium (Py/Tr) ratio, the nitrogen atoms (N) in the methylated N-(3-pyridylmethyl) chitosan chloride (M3-PyMeChC)/the phosphorus atoms (P) in DNA (N/P) ratio, and the physicochemical properties of nanopolyplexes on transfection efficiency. The water-soluble chitosan derivative, M3-PyMeChC, was used as a non-viral vector to deliver pEGFP-C2 into human hepatoma (Huh7) cell lines. The results revealed that higher molecular weight M3-PyMeChC was able to form complexes completely with DNA at lower N/P ratios than that with lower molecular weights, which led to higher transfection efficiency. Moreover, the M3-PyMeChC with higher Py/Tr ratios showed superior transfection efficiency at lower Py/Tr ratios at all N/P ratios studied. The highest transfection efficiency for the nanopolyplexes occurred for a molecular weight of 82 kDa at a N/P ratio of 5. The results indicated that the hydrophobic effect of pyridinium moiety could enhance gene transfection efficiency, which can be attributed to the dissociation of DNA from nanopolyplexes. High Py/Tr ratios in nanopolyplexes tended to decrease cytotoxicity due to delocalization of positive charge into a pyridine ring while high N/P ratios and molecular weight increased cytotoxicity. Our results showed that the vector was able to spread the positive charge by delocalizing it into a heterocyclic ring, suggesting to a promising approach to mediate higher levels of gene transfection.

Improved stability and efficacy of chitosan/pDNA complexes for gene delivery

Biotechnology Letters, 2014

Among polymeric polycations, chitosan has emerged as a powerful carrier for gene delivery. Only a few studies have focused on the stability of the chitosan/DNA complex under storage, although this is imperative for nanomedicinal applications. Here, we synthesized polyelectrolyte complexes at a charge ratio of 10 using 50 kDa chitosan and plasmid (p)DNA that encodes a GFP reporter. These preparations were stable up to 3 months at 4°C and showed reproducible transfection efficiencies in vitro in HEK293 cells. In addition, we developed a methodology that increases the in vitro transfection efficiency of chitosan/pDNA complexes by 150 % with respect to standard procedures. Notably, intracellular pDNA release and transfected cells peaked 5 days following transection of mitotically active cells. These new developments in formulation technology enhance the potential for polymeric nanoparticle-mediated gene therapy.

A novel glutathione modified chitosan conjugate for efficient gene delivery

2011

A novel non-viral gene vector based on poly[poly(ethylene glycol) methacrylate] (PMPEG) and L-glutathione (GSH) grafted chitosan (CS) has been fabricated. First, well-defined brush-like PMPEG living polymers with dithioester residues were prepared by the reversible addition-fragmentation chain transfer (RAFT) polymerization and grafted onto the allylchitosan via radical coupling method. Then, the tripeptide GSH was introduced onto the end of PMPEG chain to give a CS-PMPEG-GSH conjugate. In comparison with pristine chitosan, CS-PMPEG-GSH conjugate could not only condense plasmid DNA (pDNA) and prevent the condensed CS-PMPEG-GSH/pDNA nanoparticle self-aggregation, but also increase the binding ability to cell membrane efficiently and improve decondensed ability of pDNA from the nanoparticles in cytoplasm which thus has resulted in the higher transfection efficiency in mouse embryonic fibroblast cells (NIH3T3). In addition, cytotoxicity assays showed that the conjugate is less cytotoxic than CS, and still retain the cationic polyelectrolyte characteristic as chitosan. These results indicate that the non-viral vector is a promising candidate for gene therapy in clinical application.

Enhanced chitosan-DNA interaction by 2-Acrylamido-2-methylpropane coupling for efficient transfection in cancer cells

J. Mater. Chem. B, 2015

Gene therapy is the treatment of human disorders by the introduction of genetic material to specific target cells of a patient. Chitosan and its derivatives show excellent biological properties including biocompatibility, biodegradability and nonallergenicity. Primary amines of chitosan are responsible for its cationic nature and hence binding and protection of DNA for intracellular delivery. But the transfection efficiency of chitosan based gene transporters is severely hampered by its poor physical properties such as low water solubility and high viscosity. In this study, primary amines of low molecular weight (LMW) chitosan were coupled with 2-acrylamido-2-methylpropane sulphonic acid (AMP) making it water soluble for its application in gene delivery. AMP modified chitosan (CSAMP) showed an enhanced interaction with DNA and a higher buffering capacity due to AMP amines leading to a higher transfection efficiency in cancer cells (A549, HeLa and HepG 2 ) compared to native chitosan and Lipofectamine s . In vivo studies in Balb/c through intravenous injection demonstrated a higher luciferase expression compared to LMW chitosan.