title: Methylated N-(4-pyridinylmethyl) chitosan as a novel effective safe gene carrier.
abstract: The objective of this study was to study the transfection efficiency of quaternized N-(4-pyridinylmethyl) chitosan; TM-Py-CS, using the pDNA encoding green fluorescent protein (pEGFP-C2) on human hepatoma cell lines (Huh 7 cells). The factors affecting the transfection efficiency, e.g. degree of quaternization (DQ), the extent of N-pyridinylmethyl substitution (ES) and weight ratio, have been investigated. The results revealed that TM-Py-CS was able to condense with pDNA. Illustrated by agarose gel electrophoresis, complete complexes of TM(69)Py(62)CS/DNA were formed at weight ratio above 1.1, whereas those of TM(53)Py(40)CS/DNA and TM(52)Py(13)CS/DNA were above 1.8 and 8, respectively. TM(69)Py(62)CS showed superior transfection efficiency to TM(53)Py(40)CS, TM(52)Py(13)CS, TM(65)CS and TM(43)CS at all weight ratios tested. The highest transfection efficiency of TM(69)Py(62)CS/DNA complexes was found at weight ratio of 4. The results indicated that the improved gene transfection was possibly due to 4-pyridinylmethyl substitution on CS which promoted the interaction and condensation with DNA as well as N-quaternization which increased CS water solubility. In cytotoxicity studies, high concentration of TM-Py-CS and TM-CS could decrease the Huh 7 cell viability. In conclusion, this novel CS derivative, TM(69)Py(62)CS, showed promising potential as a gene carrier by efficient DNA condensation and mediated higher level of gene transfection.
authors.affiliation: Nanotechnology for Drug/Gene Delivery Systems Group, Faculty of Pharmacy, Silpakorn University, Nakhonpathom, Thailand. Praneet@email.pharm.su.ac.th
authors.forename: Praneet
authors.initials: P
authors.lastname: Opanasopit
authors.forename: Warayuth
authors.initials: W
authors.lastname: Sajomsang
authors.forename: Uracha
authors.initials: U
authors.lastname: Ruktanonchai
authors.forename: Varissaporn
authors.initials: V
authors.lastname: Mayen
authors.forename: Theerasak
authors.initials: T
authors.lastname: Rojanarata
authors.forename: Tanasait
authors.initials: T
authors.lastname: Ngawhirunpat
mesh_terms: D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D048271:Chitosan / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry; D004247:DNA / Q000096:biosynthesis / Q000235:genetics; D004337:Drug Carriers / Q000138:chemical synthesis / Q000737:chemistry*; D004563:Electrochemistry; D004926:Escherichia coli / Q000235:genetics; D018014:Gene Transfer Techniques; D006801:Humans; D007202:Indicators and Reagents; D010316:Particle Size; D010957:Plasmids / Q000235:genetics; D017550:Spectroscopy, Fourier Transform Infrared; D014162:Transfection
chemical_list: D004337:Drug Carriers; D007202:Indicators and Reagents; C534744:methylated N-(4-pyridinylmethyl)chitosan; D004247:DNA; D048271:Chitosan