Publications by authors named "Seonmok Kim"

6 Publications

  • Page 1 of 1

Fabrication and Characterization of Polysaccharide Metallohydrogel Obtained from Succinoglycan and Trivalent Chromium.

Polymers (Basel) 2021 Jan 8;13(2). Epub 2021 Jan 8.

Department of Bioscience and Biotechnology, Microbial Carbohydrate Resource Bank (MCRB), Konkuk University, Seoul 05029, Korea.

In the present study, a polysaccharide metallohydrogel was successfully fabricated using succinoglycan and trivalent chromium and was verified via Fourier transform infrared spectroscopy, differential scanning calorimetry analysis, thermogravimetric analysis (TGA), field emission scanning electron microscopy, and rheological measurements. Thermal behavior analysis via TGA indicated that the final mass loss of pure succinoglycan was 87.8% although it was reduced to 65.8% by forming a hydrogel with trivalent chromium cations. Moreover, succinoglycan-based metallohydrogels exhibited improved mechanical properties based on the added concentration of Cr and displayed a 10 times higher compressive stress and enhanced storage modulus (G') of 230% at the same strain. In addition, the pore size of the obtained SCx could be adjusted by changing the concentration of Cr. Gelation can also be adjusted based on the initial pH of the metallohydrogel formulation. This was attributed to crosslinking between chromium trivalent ions and hydroxyl/carboxyl groups of succinoglycan, each of which exhibits a specific pH-dependent behavior in aqueous solutions. It could be used as a soft sensor to detect Cr in certain biological systems, or as a soft matrix for bioseparation that allows control of pore size and mechanical strength by tuning the Cr concentration.
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http://dx.doi.org/10.3390/polym13020202DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7827257PMC
January 2021

Biocompatible and self-recoverable succinoglycan dialdehyde-crosslinked alginate hydrogels for pH-controlled drug delivery.

Carbohydr Polym 2020 Dec 16;250:116934. Epub 2020 Aug 16.

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:

We fabricated polysaccharide-based hydrogels, which are biocompatible, self-recoverable and pH-sensitive. Succinoglycan dialdehyde (SGDA) was first synthesized from bacterial succinoglycan directly isolated from Sinorhizobium meliloti and then hydrazine-functionalized alginate (HZ-Alg) was prepared to form SGDA-crosslinked alginate hydrogels (SGDA/HZ-Alg) without any catalyst. Due to structural characteristics of SGDA, SGDA/HZ-Alg were effectively obtained in a short time even at low concentrations (0.94-1.57 wt%) where they exhibited self-recoverable and tunable rheological properties corresponding to efficiency of recovery from 93.2%-97.9%. Moreover, SGDA/HZ-Alg showed the pH-responsive degradation as well as pH-controlled release behavior for 5-fluorouracil. 5-Fluorouracil was released approximately 98 % at pH 2.0 within 12 h, but not completely released even after 24 h at pH 7.4. The WST-8 assay results also demonstrated that SGDA/HZ-Alg did not show any cytotoxicity against HEK-293 cells. Since the suggested hydrogels are biocompatible, rheologically self-recoverable and tunable, and pH-controllable, they would be potential biomaterials for the hydrogel-based drug delivery systems.
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http://dx.doi.org/10.1016/j.carbpol.2020.116934DOI Listing
December 2020

Structural Characterization of Glycerophosphorylated and Succinylated Cyclic β-(1→2)-d-Glucan Produced by 1021.

Polymers (Basel) 2020 Sep 12;12(9). Epub 2020 Sep 12.

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

produces different types of surface polysaccharides. Among them, cyclic β-(1→2)-d-glucan is located in the periplasmic space of rhizobia and plays an important role in the adaptation of bacteria to osmotic adaptation. Cyclic β-(1→2)-d-glucan (CG), synthesized from 1021, has a neutral and anionic form. In the present study, we characterized the exact chemical structures of anionic CG after purification using size exclusion s (Bio-Gel P-6 and P-2) chromatography, and DEAE-Sephadex anion exchange chromatography. The exact structure of each isolated anionic CG was characterized using various analytical methods such as nuclear magnetic resonance (NMR), attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and matrix associated laser desorption ionization-time of Flight (MALDI-TOF) mass spectrometry. The precise chemical structures of novel anionic CG molecules were elucidated by various NMR spectroscopic analyses, including H, C, P, and 2D HSQC NMR spectroscopy. As a result, we discovered that anionic CG molecules have either glycerophosphoryl or succinyl residues at C6 positions of a neutral CG. In addition, the results of MALDI-TOF mass spectrometric analysis confirmed that there are two types of patterns for anionic CG peaks, where one type of peak was the succinylated CG (SCG) and the other was glycerophospholated CG (GCG). In addition, it was revealed that each anionic CG has one to four substituents of the succinyl group of SCG and glycerophosphoryl group of GCG, respectively. Anionic CG could have potential as a cyclic polysaccharide for drug delivery systems and a chiral separator based on the complexation with basic target molecules.
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http://dx.doi.org/10.3390/polym12092073DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7569799PMC
September 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

Succinoglycan dialdehyde-reinforced gelatin hydrogels with toughness and thermal stability.

Int J Biol Macromol 2020 Apr 23;149:281-289. Epub 2020 Jan 23.

Department of Bioscience and Biotechnology, Microbial Carbohydrate Resource Bank (MCRB), Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, South Korea; Institute for Ubiquitous Information Technology and Applications (UBITA), Center for Biotechnology Research in UBITA (CBRU), Konkuk University, Seoul 05029, South Korea. Electronic address:

Pure gelatin hydrogel (PG) has limited practical applications due to their thermal instability and unfavorable mechanical properties. To overcome these limitations, dually crosslinked hydrogels were developed by imparting chemical crosslinking to existing physically crosslinked gelatin hydrogel networks using succinoglycan dialdehyde (SGDA) as a macromolecular crosslinker. SGDA-reinforced gelatin hydrogels (SGDA/Gels) displayed an 11 times higher compressive stress under identical deformation strain and a 1040% improvement in storage modulus (G') than PG. In addition, chemical crosslinking induced by SGDA increased the thermal stability of SGDA/Gels, such that they did not decompose at 60 °C, as confirmed by oscillatory temperature ramp experiments. The newly synthesized SGDA/Gels with reinforced networks and thermal stability exhibit potential for long-term use as controlled drug delivery carriers and 3D cell culture scaffolds for tissue engineering.
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http://dx.doi.org/10.1016/j.ijbiomac.2020.01.228DOI Listing
April 2020

Cyclodextrin functionalized agarose gel with low gelling temperature for controlled drug delivery systems.

Carbohydr Polym 2019 Oct 20;222:115011. Epub 2019 Jun 20.

Department of Bioscience and Biotechnology, Microbial Carbohydrate Resource Bank (MCRB), Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 05029, South Korea; Institute for Ubiquitous Information Technology and Applications (UBITA), Center for Biotechnology Research in UBITA (CBRU), Konkuk University, Seoul, 05029, South Korea. Electronic address:

Conventional agaroses with high gelling temperature are limited to apply to the field of drug delivery. In this study, β-cyclodextrin (βCD) functionalized agarose (CFA) with low gelling temperature was successfully prepared from ethylenediamine-functionalized agarose using mono-succinyl βCD. The gelling temperature of CFA dramatically decreased to 26.7 °C from 65 °C and the melting temperature declined from 95 °C to 66.1 °C. Upon drug loading, CFA can be used at 30 °C because of its low gelling temperature compared to agarose. CFA gel could be used both for bovine serum albumin as a full release, and for the doxorubicin (DOX) for sustained release, via inclusion complexation of βCD. Furthermore, cytotoxicity tests revealed that CFA was noncytotoxic. DOX in the CFA gel could retain the anti-cancer activity. Newly synthesized CFA with low gelling temperature offer a new means for the development of hydrogel-based delivery systems for a variety of therapeutic drugs.
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http://dx.doi.org/10.1016/j.carbpol.2019.115011DOI Listing
October 2019