Cuu Khoa Nguyen
Vietnam Academy of Science and Technology
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Publication
Featured researches published by Cuu Khoa Nguyen.
Journal of Biomaterials Science-polymer Edition | 2013
Dai Hai Nguyen; Ngoc Quyen Tran; Cuu Khoa Nguyen
In recent years, injectable chitosan-based hydrogels have been widely studied towards biomedical applications because of their potential performance in drug/cell delivery and tissue regeneration. In this study, we introduce a simple and organic solvent-free method to prepare tyramine–tetronic–grafted chitosan (TTeC) via activation of four terminal hydroxyl groups of tetronic, partial tyramine conjugate into the activated product and grafting the remaining activated moiety of tetronic-tyramine onto chitosan. The grafted copolymer was well characterized by UV–Visible, 1H NMR, and Thermogravimetric analysis. The aqueous TTeC copolymer solution rapidly formed hydrogel in the presence of horseradish peroxidase (HRP) and hydrogen peroxide (H2O2) at physiological conditions. The gelation time of the hydrogel was performed within a time period of 4–60 s, when the concentrations of HRP, H2O2, and polymers varied. The hydrogel exhibited highly porous structure which could be controlled by using H2O2. In vitro cytotoxicity study with Human Foreskin Fibroblast cell using live/dead assay indicated that the hydrogel had high cytocompatibility and could play a role as a scaffold for cell adhesion. The injectable hydrogels did not cause any inflammation after two weeks and one day of the in vivo injection. The obtained results demonstrated a great potential of the TTeC hydrogel in biomedical applications.
International Journal of Polymer Analysis and Characterization | 2015
Thi Bich Tram Nguyen; Thi Tram Chau Nguyen; Hoang Chinh Tran; Cuu Khoa Nguyen; Ngoc Quyen Tran
We established two formulas to predict molecular weight of polyaminoamine dendrimers and their alkylated derivatives, based on the theoretical number of protons at specific positions in the dendrimers and the true value of the integral values of these protons appearing in proton nuclear magnetic resonance spectra. Calculated results indicated that molecular weight of the dendrimers is approximately equal to results from mass spectrometry. Degrees of alkylation were easily calculated for each dendrimer-alkylated derivative. According to the obtained results, we confirm that the use of the proton spectra can be an effective method to predict molecular weight of dendrimers.
Materials Science and Engineering: C | 2017
Thu Thao Nguyen Thi; Tuong Vi Tran; Ngoc Quyen Tran; Cuu Khoa Nguyen; Dai Hai Nguyen
Porous nanosilica (PNS) has been attracting a great attention in fabrication carriers for drug delivery system (DDS). However, unmodified PNS-based carriers exhibited the initial burst release of loaded bioactive molecules, which may limit their potential clinical application. In this study, the surface of PNS was conjugated with adamantylamine (A) via disulfide bonds (PNS-SS-A) which was functionalized with cyclodextrin-heparin-polyethylene glycol (CD-HPEG) for redox triggered doxorubicin (DOX) delivery. The modified PNS was successfully formed with spherical shape and diameter around 50nm determined by transmission electron microscopy (TEM). DOX was efficiently trapped in the PNS-SS-A@CD-HPEG and slowly released in phosphate buffered saline (PBS) without any initial burst effect. Importantly, the release of DOX was triggered due to the cleavage of the disulfide bonds in the presence of dithiothreitol (DTT). In addition, the MTT assay data showed that PNS-SS-A@CD-HPEG was a biocompatible nanocarrier and reduced the toxicity of DOX. These results demonstrated that PNS-SS-A@CD-HPEG has great potential as a novel nanocarrier for anticancer drug in cancer therapy.
Materials Science and Engineering: C | 2017
Thi Tram Chau Nguyen; Cuu Khoa Nguyen; Thi-Hiep Nguyen; Ngoc Quyen Tran
In the study, four kinds of pluronics (P123, F68, F127 and F108) with varying hydrophilic-lipophilic balance (HLB) values were modified and conjugated on 4th generation of polyamidoamine dendrimer (PAMAM). The obtained results from FT-IR, 1H NMR and GPC showed that the pluronics effectively conjugated on the dendrimer. The molecular weight of four PAMAM G4.0-Pluronics and its morphologies are in range of 200.15-377.14kDa and around 60-180nm in diameter by TEM, respectively. Loading efficiency and release of hydrophobic fluorouracil (5-FU) anticancer drug were evaluated by HPLC; Interesting that the dendrimer nanocarrier was conjugated with the highly lipophilic pluronic P123 (G4.0-P123) exhibiting a higher drug loading efficiency (up to 76.25%) in comparison with another pluronics. Live/dead fibroblast cell staining assay mentioned that all conjugated nanocarriers are highly biocompatible. The drug-loaded nanocarriers also indicated a highly anti-proliferative activity against MCF-7 breast cancer cell. The obtained results demonstrated a great potential of the highly lipophilic pluronics-conjugated nanocarriers in hydrophobic drugs delivery for biomedical applications.
Macromolecular Research | 2014
Thanh Son Cu; Van Du Cao; Cuu Khoa Nguyen; Ngoc Quyen Tran
AbstractIn this paper, we report the preparation and stabilization of colloidal silver nanoparticle solution, with the assistance of chitosan dihydroxyphenyl acetamide (CDHPA), or oligochitosan dihydroxyphenyl acetamide (OCDHPA). The structure of the chitosan derivatives were characterized by nuclear magnetic resonance (1H NMR) spectroscopy. The morphology of the synthesized silver core-chitosan shell nanoparticles were observed by transmission electron microscopy (TEM) and X-ray diffraction (XRD) techniques, and showed a well-defined core-shell structure of polymer-coated silver nanoparticles (AgNPs). The core-shell NPs exhibited a strong antibacterial activity against E. coli and S. aureus, at a very low concentration of AgNPs (2.5 ppm). Our studies offer a new method for the preparation and protection of silver nanoparticles for antibacterial applications.
Materials Science and Engineering: C | 2018
Vu Minh Thanh; Thi-Hiep Nguyen; Tuong Vi Tran; Uyen-Thi Phan Ngoc; Minh Nhat Ho; Thi Thinh Nguyen; Yen Nguyen Tram Chau; Van Thu Le; Ngoc Quyen Tran; Cuu Khoa Nguyen; Dai Hai Nguyen
In this report, poly(amide amine) (PAMAM) dendrimer and Heparin-grafted-monomethoxy polyethylene glycol (HEP-mPEG) were synthesized and characterized. In aqueous solution, the generation 4 PAMAM dendrimers (G4.0-PAMAM) existed as nanoparticles with particle size of 5.63nm. However, after electrostatic complexation with HEP-mPEG to form a core@shell structure G4.0-PAMAM@HEP-mPEG, the size of nanoparticles was significantly increased (73.82nm). The G4.0-PAMAM@HEP-mPEG nanoparticles showed their ability to effectively encapsulate doxorubicin (DOX) for prolonged and controlled release. The cytocompatibility of G4.0-PAMAM@HEP-mPEG nanocarriers was significantly increased compared with its parentally G4.0-PAMAM dendrimer in both mouse fibroblast NIH3T3 and the human tumor HeLa cell lines. DOX was effectively encapsulated into G4.0-PAMAM@HEP-mPEG nanoparticles to form DOX-loaded nanocarriers (DOX/G4.0-PAMAM@HEP-mPEG) with high loading efficiency (73.2%). The release of DOX from DOX/G4.0-PAMAM@HEP-mPEG nanocarriers was controlled and prolonged up to 96h compared with less than 24h from their parentally G4.0-PAMAM nanocarriers. Importantly, the released DOX retained its bioactivity by inhibiting the proliferation of monolayer-cultured cancer HeLa cells with the same degree of fresh DOX. This prepared G4.0-PAMAM@HEP-mPEG nanocarrier can be a potential candidate for drug delivery systems with high loading capacity and low systemic toxicity in cancer therapy.
Advances in Natural Sciences: Nanoscience and Nanotechnology | 2017
Cuu Khoa Nguyen; Ngoc Quyen Tran; Thi Phuong Nguyen; Dai Hai Nguyen
Over the past decades, biopolymer-based nanomaterials have been developed to overcome the limitations of other macro- and micro- synthetic materials as well as the ever increasing demand for the new materials in nanotechnology, biotechnology, biomedicine and others. Owning to their high stability, biodegradability, low toxicity, and biocompatibility, biopolymer-based nanomaterials hold great promise for various biomedical applications. The pursuit of this review is to briefly describe our recent studies regarding biocompatible biopolymer-based nanomaterials, particularly in the form of dendrimers, hydrogels, and hydrogel composites along with the synthetic and modification approaches for the utilization in drug delivery, tissue engineering, and biomedical implants. Moreover, in vitro and in vivo studies for the toxicity evaluation are also discussed.
Green Processing and Synthesis | 2016
Thi Bich Tram Nguyen; Le Hang Dang; Thi Thanh Thuy Nguyen; Dai Lam Tran; Dai Hai Nguyen; Van Toan Nguyen; Cuu Khoa Nguyen; Thi-Hiep Nguyen; Van Thu Le; Ngoc Quyen Tran
Abstract In this study, in order to enhance the aqueous solubility and to overcome the limitation of curcumin (Cur) in free form, as well as to develop a carrier for transdermal delivery of hydrophobic pharmaceutical agents such as Cur, a sonicated synthetic process of nanocurcumin (nCur) in thermally responsive Chitosan-g-Pluronic (CP) copolymer is disclosed herein. The use of CP copolymer solution as a dispersant medium is a very attractive method to avoid the use of toxic organic solvent and non-biocompatible surfactant. The obtained Cur nanoparticles had a fairly narrow distribution of 8–23 nm. nCur-dispersed CP solution showed good stability with no change in color characteristic and no phase separation after 1 month of storage. Rheological characterization of CP hydrogels had indicated sol-gel transition at the same temperature (35°C). Interestingly, the rate of Cur release for this system can be conveniently modulated as transdermal drug delivery.
Journal of Polymer Research | 2012
Ngoc Quyen Tran; Thi Kim Dung Hoang; Cuu Khoa Nguyen
Star-shaped poly(methyl acrylate) (PMA) was synthesized using tri(2-bromopropionate) glyceride as the initiator and methyl acrylate as the monomer via atom transfer radical polymerization (ATRP). The structures of tri(2-bromopropionate) glyceride and PMA were characterized by IR, GC-MS, 1H NMR, and 13C NMR. The reinforcing effects of this star-shaped PMA on polyvinylchloride (PVC) in various PMA/PVC blends were evaluated. The results indicated that a blend containing 1% star-shaped PMA exhibits an 18% increase in the elastic modulus and a 10% increase in tensile strength compared to PVC. Moreover, the impact resistance of the blend was 30% higher than that for PVC. The blend also exhibited high thermal stability. SEM images showed that the star-shaped PMA and PVC are highly compatible when blended, which causes the enhanced elasticity of the blend.
BioMed Research International | 2017
Thanh Luan Nguyen; Thi-Hiep Nguyen; Cuu Khoa Nguyen; Dai Hai Nguyen
Heparin (Hep) conjugated to poly (amidoamine) dendrimer G3.5 (P) via redox-sensitive disulfide bond (P-SS-Hep) was studied. The redox and pH dual-responsive nanocarriers were prepared by a simple method that minimized many complex steps as previous studies. The functional characterization of G3.5 coated Hep was investigated by the proton nuclear magnetic resonance spectroscopy. The size and formation were characterized by the dynamic light scattering, zeta potential, and transmission electron microscopy. P-SS-Hep was spherical in shape with average diameter about 11 nm loaded with more than 20% letrozole. This drug carrier could not only eliminate toxicity to cells and improve the drugs solubility but also increase biocompatibility of the system under reductive environment of glutathione. In particular, P-SS-Hep could enhance the effectiveness of cancer therapy after removing Hep from the surface. These results demonstrated that the P-SS-Hep conjugates could be a promising candidate as redox and pH responsive nanocarriers for cancer chemotherapy.