A Novel Injectable pH–Temperature Sensitive Hydrogel Containing Chitosan–Insulin Electrosprayed Nanosphere Composite for an Insulin Delivery System in Type I Diabetes Treatment

Thuy An Trinh,Thai Minh Duy Le,Hoang Gia Vinh Ho,Thi Cam Thach To,Vu Viet Linh Nguyen,Dai Phu Huynh,Doo Sung Lee 한국고분자학회 2021 한국고분자학회 학술대회 연구논문 초록집 Vol.46 No.1

Faculty of Materials Technology, Ho Chi Minh University of Technology (HCMUT)/Vietnam National University Ho Chi Minh City; ¹School of Chemical Engineering and Theragnostic Macromolecules Research Center, Sungkyunkwan University; ²Vietnam National University Ho Chi Minh City/National Key Laboratory of Polymer and Composite Materials, Ho Chi Minh University of Technology, Vietnam National University; ³Faculty of Materials Technology, Ho Chi Minh University of Technology (HCMUT)/ Vietnam National University Ho Chi Minh City/Research Center for Polymeric Materials, Ho Chi Minh University of Technology, Vietnam National University In this research, a novel insulin composite delivery system was prepared and characterized. Insulin drug was loading in chitoshan nanospheres using electrospraying method, a pH- and temperature-sensitive biodegradable hydrogel, which is an oligomer serine-poly(lactide)-poly(ethylene glycol)-poly (lactide)-oligomer serine (OS-PLA-PEG-PLA-OS) pentablock copolymer was used as a matrix to containing chitosan–insulin electro sprayed nanospheres (CIN). The properties of the OS-PLA-PEG-PLA-OS pentablock copolymer and the chitosan–insulin nanoparticles such as sol-gel transition, degradation in vitro and in vivo were characterized. The results showed that the chitosan–insulin nanospheres uniformly distributed in the matrix had a reinforcing effect on the mechanical properties and prolonged the degradation time of the hydrogel depot under body conditions. In addition, the cytotoxicity experiment results indicate that the composite could be used as a biomaterial for drug delivery system. The composite solutions accommodating different concentrations of the chitosan–insulin nanospheres were subcutaneously injected into induced diabetic BALB/c mice to study the in vivo insulin-release profile. The result showed that insulin concentrations in blood plasma were maintained at a steady-state level. Furthermore, the bio-properties of the insulin were retained and it showed a blood glucose level reducing effect for more than 60 hours after injection to a streptozotocin (STZ)-induced diabetic mouse model. The results suggested that this injectable pH–temperature sensitive hydrogel containing chitosan– insulin electro sprayed nanosphere composites has promising potential applications for type 1 diabetes treatment.

Preparation of new dinuclear half-titanocene complexes with <i>ortho-</i> and <i>meta</i>-xylene linkages and investigation of styrene polymerization

Linh, Nguyen Thuy Ba,Huyen, Nguyen Thi Dieu,Noh, Seok Kyun,Lyoo, Won Seok,Lee, Dong-Ho,Kim, Yongman Elsevier 2009 Journal of organometallic chemistry Vol.694 No.21

<P><B>Graphical abstract</B></P><P>Dinuclear half-titanocene bearing a xylene bridge, <I>ortho-</I> and <I>meta-</I>xylene, have been successfully synthesized and introduced for styrene polymerization. The activities of the catalysts with rigid <I>ortho</I>- and <I>meta</I>-xylene bridges were higher than those of catalysts with flexible pentamethylene bridges. Activity of the catalysts increased with higher temperature and [Al]:[Ti].</P><ce:figure></ce:figure> <P><B>Abstract</B></P><P>Half-titanocene is well-known as an excellent catalyst for the preparation of SPS (syndiotactic polystyrene) when activated with methylaluminoxane (MAO). Dinuclear half-sandwich complexes of titanium bearing a xylene bridge, <I>(Ti</I>Cl<SUB>2</SUB>L<I>)<SUB>2</SUB>{(μ-η<SUP>5</SUP>, η<SUP>5</SUP>-C<SUB>5</SUB>H<SUB>4</SUB>-ortho-(CH<SUB>2</SUB>–C<SUB>6</SUB>H<SUB>4</SUB>–CH<SUB>2</SUB>)C<SUB>5</SUB>H<SUB>4</SUB>}</I>, (<B>4</B> (L=Cl), <B>7</B> (L=O-2,6-<I>i</I>Pr<SUB>2</SUB>C<SUB>6</SUB>H<SUB>3</SUB>)) and <I>(Ti</I>Cl<SUB>2</SUB>L<I>)<SUB>2</SUB>{(μ-η<SUP>5</SUP>, η<SUP>5</SUP>-C<SUB>5</SUB>H<SUB>4</SUB>-meta-(CH<SUB>2</SUB>–C<SUB>6</SUB>H<SUB>4</SUB>–CH<SUB>2</SUB>)C<SUB>5</SUB>H<SUB>4</SUB>}</I> (<B>5</B> (L=Cl), <B>8</B>(L=O-2,6-<I>i</I>Pr<SUB>2</SUB>C<SUB>6</SUB>H<SUB>3</SUB>)), have been successfully synthesized and introduced for styrene polymerization. The catalysts were characterized by <SUP>1</SUP>H- and <SUP>13</SUP>C NMR, and elemental analysis. These catalysts were found to be effective in forming SPS in combination with MAO. The activities of the catalysts with rigid <I>ortho</I>- and <I>meta</I>-xylene bridges were higher than those of catalysts with flexible pentamethylene bridges. The catalytic activity of four dinuclear half-titanocenes increased in the order of <B>4</B><<B>5</B><<B>7</B><<B>8</B>. This result displays that the <I>meta</I>-xylene bridged catalyst is more active than the <I>ortho</I>-xylene bridged and that the aryloxo group at the titanium center is more effective at promoting catalyst activity compared to the chloride group at the titanium center. Temperature and ratio of [Al]:[Ti] had significant effects on catalytic activity. Polymerizations were conducted at three different temperatures (25, 40, and 70°C) with variation in the [Al]:[Ti] ratio from 2000 to 4000. It was observed that activity of the catalysts increased with increasing temperature, as well as higher [Al]:[Ti]. Different xylene linkage patterns (<I>ortho</I> and <I>meta</I>) were recognized to be a principal factor leading to the characteristics of the dinuclear catalyst due to its different spatial arrangement, causing dissimilar intramolecular interactions between the two active sites.</P>

Functional nanofiber mat of polyvinyl alcohol/gelatin containing nanoparticles of biphasic calcium phosphate for bone regeneration in rat calvaria defects

Ba Linh, Nguyen Thuy,Lee, Kap‐,Ho,Lee, Byong‐,Taek Wiley Subscription Services, Inc., A Wiley Company 2013 Journal of biomedical materials research. Part A Vol.101 No.8

<P><B>Abstract</B></P><P>New biodegradable mats was successfully obtained by functional polyvinyl alcohol (PVA)/Gelatin (GE) blend fiber mats containing different BCP amounts (20, 40, and 50 w/v%) of biphasic calcium phosphate (BCP) nanoparticles for bone regeneration. BCP nanoparticles were loaded and dispersed successfully in the PVA/GE fibrous matrix. The addition of BCP was found to have increased fiber diameter, tensile strength, osteoblast cell adhesion, proliferation, and protein expression. Compared to the others, the 50% BCP‐loaded electrospun PVA/GE fibers had the most favorable mechanical properties, cell attachment and growth, and protein expression. <I>In vivo</I> bone formation was examined using rat models, and increased bone formation was observed for the 50% BCP‐loaded electrospun PVA/GE blends within 2 and 4 weeks. This result suggests that the 50% BCP‐PVA/GE composite nanofiber mat has high potential for use in the field of bone regeneration and tissue engineering. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.</P>

Using sulfate-functionalized Hf-based metal–organic frameworks as a heterogeneous catalyst for solvent-free synthesis of pyrimido[1,2-a] benzimidazoles via one-pot three-component reaction

Minh-Huy Dinh Dang,Linh Ho Thuy Nguyen,Trang Thi Thu Nguyen,Ngoc Xuan Dat Mai,Phuong Hoang Tran,Tan Le Hoang Doan 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.103 No.-

Functionalized metal–organic frameworks have recently received significant attention in heterogeneouscatalysis applications due to their high catalytic activity. In this work, a sulfate-functionalized Hf-clusterbasedmetal–organic framework was prepared via sulfation of a Hf-MOF, named Hf-BTC, constructed byHf6 clusters and 1,3,5-tricarboxylate linkers. The Hf-BTC-SO4 material was consequently demonstrated tobe an efficiently reusable superacid catalyst for a one-pot three-component reaction of pyrimido[1,2-a]benzimidazoles synthesis. The reaction catalyzed by the sulfated Hf-BTC could be carried out under mildand solvent-free conditions and give superior performance in a wide range of substrates. According todetailed investigation, the good catalytic performance of the sulfated-functionalized MOF likely originatesfrom the high-porosity framework and the high active sites of the functionalized clusters. Importantly, the catalyst could be easy to recover and reuse the functionalized framework several timeswith minor changes in catalytic efficiency.

Total Peroxynitrite Scavenging Capacity of Phenylethanoid and Flavonoid Glycosides from the Flowers of <i>Buddleja officinalis</i>

Tai, Bui Huu,Jung, Bong Yong,Cuong, Nguyen Manh,Linh, Pham Thuy,Tung, Nguyen Huu,Nhiem, Nguyen Xuan,Huong, Tran Thu,Anh, Ngo Thi,Kim, Jeong Ah,Kim, Sang Kyum,Kim, Young Ho Pharmaceutical Society of Japan 2009 Biological & pharmaceutical bulletin Vol.32 No.12

<P>Nine compounds, including six phenylethanoid glycosides: acteoside (1); bioside (2); echinacoside (3); poliumoside (4); phenylethyl glycoside (5); salidroside (6) and three flavonoids; linarin (7); apigenin (8); isorhoifolin (9), were isolated from the flowers of <I>Buddleja officinalis</I> M<SMALL>AXIM</SMALL>. (Buddlejaceae). Chemical structures were confirmed by <SUP>1</SUP>H-, and <SUP>13</SUP>C-NMR, and MS spectral methods and compared with those reported in the literature. Antioxidant activities of the methanol and water extracts, and all isolated compounds were evaluated using the total oxidant scavenging capacity (TOSC) assay against peroxynitrite. Results of the assay showed that the phenylethanoid glycosides, a major class of compounds of the flowers of <I>B. officinalis</I>, possess strong antioxidant activity. Of these, acteoside, echinacoside and poliumoside have 9.9-, 9.8- and 9.5-fold TOSC value, respectively, compared with the positive control, Trolox.</P>

An effective combination of reusable Pd@MOF catalyst and deep eutectic solvents for high-performance C–C coupling reaction

Minh-Huy Dinh Dang,Trang Thi Thu Nguyen,Bao Quang Gia Le,Linh Ho Thuy Nguyen,Ngoc Xuan Dat Mai,My Van Nguyen,Phuong Hoang Tran,Tan Le Hoang Doan 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.111 No.-

Pd-incorporated Zr-based metal–organic framework containing sulfone groups, named Pd(II)BUT-11, wassuccessfully prepared by dispersing the sulfone-functionalized MOF in Pd(OAc)2 solution. X-ray diffraction,scanning electron microscopy, N2 isotherm sorption, X-ray photoelectron spectroscopy, and thermogravimetricanalysis were applied to determine the features of the Pd-incorporated MOF. In the catalyticstudies, Pd(II)@BUT-11 was shown to be an efficient heterogeneous catalyst for synthesizing various stilbenederivatives via the cross-coupling Heck reaction with DABCO-derived deep eutectic solvent (DES) asa green solvent. Notably, the catalyst and the solvent could be recovered and reused, with their activityand structure remaining stable throughout several trials. The method provides an alternative solution tothe conventional catalysts and solvents, resulting in a green and efficient stilbene synthesis process. Furthermore, the stilbenes were separated by extraction with ethyl acetate due to the low solubility ofDES with this solvent.