Publications by authors named "Yiluo Hu"

5 Publications

  • Page 1 of 1

Azobenzene-grafted carboxymethyl cellulose hydrogels with photo-switchable, reduction-responsive and self-healing properties for a controlled drug release system.

Int J Biol Macromol 2020 Nov 10;163:824-832. Epub 2020 Jul 10.

Department of Bioscience and Biotechnology, Microbial Carbohydrate Resource Bank (MCRB), Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, South Korea; Department of Systems Biotechnology, Microbial Carbohydrate Resource Bank (MCRB), Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, South Korea. Electronic address:

In this study, multifunctional hydrogels containing host-guest complex formation between azobenzene-grafted carboxymethyl cellulose (CMC-Azo) and β-cyclodextrin (CD) dimers connected by disulfide bonds with agarose for structural support were prepared. The obtained hydrogels exhibited self-healing properties by host-guest complexation as well as gel-sol phase transition in response to ultraviolet (UV) light and reducing agents. Photo-switchable properties of the hydrogels depend on changes in the complex formation of CD-dimers through the trans(450 nm) to cis(365 nm) photo-isomerization of azobenzene. The tensile and strain sweep tests confirmed that the hydrogel's self-healing ability was 79.44% and 81.59%, respectively. In addition, drug release from the hydrogels was controlled to accelerate to 80% in 3 h using UV light or reducing agent. Since the suggested photo-switchable, reduction-responsive, and self-healable hydrogels are non-cytotoxic, they can be potentially applied as biomedical materials in the development of hydrogel-based drug release systems.
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http://dx.doi.org/10.1016/j.ijbiomac.2020.07.071DOI Listing
November 2020

Preparation of Succinoglycan Hydrogel Coordinated With Fe Ions for Controlled Drug Delivery.

Polymers (Basel) 2020 Apr 22;12(4). Epub 2020 Apr 22.

Department of Systems Biotechnology & Dept. of Bioscience and Biotechnology, Microbial Carbohydrate Resource Bank (MCRB), Center for Biotechnology Research in UBITA (CBRU), Konkuk University, Seoul 05029, Korea.

Hydrogel materials with a gel-sol conversion due to external environmental changes have potential applications in a wide range of fields, including controlled drug delivery. Succinoglycans are anionic extracellular polysaccharides produced by various bacteria, including species, which have diverse applications. In this study, the rheological analysis confirmed that succinoglycan produced by Rm 1021 binds weakly to various metal ions, including Fe cations, to maintain a sol form, and binds strongly to Fe cations to maintain a gel form. The Fe-coordinated succinoglycan (Fe-SG) hydrogel was analyzed by attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, circular dichroism (CD), and field-emission scanning electron microscopy (FE-SEM). Our results revealed that the Fe cations that coordinated with succinoglycan were converted to Fe by a reducing agent and visible light, promoting a gel-sol conversion. The Fe-SG hydrogel was then successfully used for controlled drug delivery based on gel-sol conversion in the presence of reducing agents and visible light. As succinoglycan is nontoxic, it is a potential material for controlled drug delivery.
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http://dx.doi.org/10.3390/polym12040977DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7240483PMC
April 2020

Carboxymethyl cyclosophoraoses as a flexible pH-responsive solubilizer for pindolol.

Carbohydr Polym 2017 Nov 9;175:493-501. Epub 2017 Aug 9.

Department of Bioscience and Biotechnology, Microbial Carbohydrate Resource Bank (MCRB), Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, South Korea. Electronic address:

In the present study, cyclosophoraoses (CyS) (β-1,2 linked cyclic glucans, with glucopyranose units ranging from 17 to 23) isolated from Rhizobium leguminosarum biovar viciae VF-39 were modified with carboxymethyl (CM) groups, and the pH-sensitive complexation of CM CyS with pindolol was investigated. The solubility of pindolol increased 32-fold by its complexation with 5mM CM CyS at pH 10, whereas it shows no significant change at pH 3. Pindolol, a β-adrenergic blocking agent, has a hydrophobic nature at non-ionized state, and CM CyS could solubilize efficiently pindolol in a high alkaline solution. The carboxymethylation of flexible CyS allows them to present a more suitable cavity for the hydrophobic pindolol at pH 10, which is differentiated from CM β-cyclodextrin (β-CD). It can be interpreted as that the anionic repulsion effectively modulates the flexible and distorted conformation of CyS rather than rigid annular shape of β-CD. Resultingly, the highly solubilized CM CyS/pindolol complex was characterized by UV-vis, T1 relaxation, ROESY, DOSY NMR spectroscopy, FT-IR spectroscopy, SEM, and molecular modeling studies. The antioxidant activity of pindolol was also improved 260% in the complex compared to free pindolol. The use of flexible host molecules with pH-responsive substituents would be applied in the development of smart systems for sensing or in biomedical fields.
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http://dx.doi.org/10.1016/j.carbpol.2017.08.026DOI Listing
November 2017

Synthesis, Characterization, and Retinol Stabilization of Fatty Amide-β-cyclodextrin Conjugates.

Molecules 2016 Jul 22;21(7). Epub 2016 Jul 22.

Department of Bioscience and Biotechnology, Microbial Carbohydrate Resource Bank (MCRB), Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Korea.

Amphiphilic cyclodextrin (CD) has been the object of growing scientific attention because of its two recognition sites, the cavity and the apolar heart, formed by self-assembly. In the present study, mono[6-deoxy-6-(octadecanamido)]-β-CD and mono[6-deoxy-6-(octadecenamido)]-β-CD were successfully synthesized by reacting mono-6-amino-6-deoxy-β-CD with N-hydroxysuccinimide esters of corresponding fatty acids in DMF. The structures were analyzed using nuclear magnetic resonance spectroscopy and mass spectrometry. The amphiphilic β-CDs were able to form self-assembled nano-vesicles in water, and the supramolecular architectures were characterized using fluorescence spectroscopy, dynamic light scattering, and transmission electron microscopy. Using the cavity-type nano-vesicles, all-trans-retinol was efficiently encapsulated; it was then stabilized against the photo-degradation. Therefore, the present fatty amide-β-CD conjugate will be a potential molecule for carrier systems in cosmetic and pharmaceutical applications.
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http://dx.doi.org/10.3390/molecules21070963DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6273423PMC
July 2016

Characterization and Enhanced Antioxidant Activity of the Cysteinyl β-Cyclodextrin-Baicalein Inclusion Complex.

Molecules 2016 May 27;21(6). Epub 2016 May 27.

Department of Bioscience and Biotechnology, Microbial Carbohydrate Resource Bank (MCRB), Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Korea.

Baicalein is a type of flavonoid isolated from the roots of a medicinal plant, Scutellaria baicalensis. Although it has attracted considerable attention due to its antiviral, anti-tumor, and anti-inflammatory activities, its limited aqueous solubility inhibits the clinical application of this flavonoid. The present study aimed to prepare and characterize a host-guest complex in an effort to improve the solubility and antioxidant activity of baicalein. The host molecule is a macrocyclic β-cyclodextrin (β-CD) functionalized with cysteine for a synergetic effect. The structure of the synthesized cysteinyl β-CD was analyzed using nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry. The inclusion complex with baicalein was studied by UV-vis, NMR spectroscopy, scanning electron microscopy, and X-ray powder diffractometry. The formed cysteinyl β-CD/baicalein inclusion complex efficiently improved the solubility and antioxidant ability of baicalein. Therefore, we suggest that the present cysteinyl β-CD is a potential host molecule for inclusion complexation and for bioavailability augmentation.
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http://dx.doi.org/10.3390/molecules21060703DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6273330PMC
May 2016