Oligonucleotide-based enzyme linked aptamer assay for detection of tetracycline in milk samples

Eunji Park,Ki-Jung Paeng,Insook Rhee 한국분석과학회 2017 학술대회논문집 Vol.2017 No.11

Multiphysics-informed DeepONet for predicting thermal runaway of lithium-ion batteries

Ki-Yong Oh(오기용),Jinho Jeong(정진호),Eunji Kwak(곽은지),Jun-hyeong Kim(김준형) 한국비파괴검사학회 2023 한국비파괴검사학회 춘계학술대회 초록집 Vol.2023 No.5

Instantaneous pH-Boosted Functionalization of Stellate Gold Nanoparticles for Intracellular Imaging of miRNA

Ki, Jisun,Jang, Eunji,Han, Seungmin,Shin, Moo-Kwang,Kang, Byunghoon,Huh, Yong-Min,Haam, Seungjoo American Chemical Society 2017 ACS APPLIED MATERIALS & INTERFACES Vol.9 No.21

<P>Various types of nanoprobes have recently been utilized to monitor living organisms by detecting and imaging intracellular biomarkers, such as microRNAs (miRs). We here present a simple one-pot method to prepare stellate gold nanoparticles functionalized with miR-detecting molecular beacons (SGNP-MBs); low pH conditions permitted the rapid-high loading of MBs on the surface of SGNPs. Compared to the conventional gold nanoparticle-based MBs, SGNPs carried a 4.5-fold higher load of MBs and exhibited a 6.4-fold higher cellular uptake. We demonstrated that SGNP-MBs were successfully internalized in human gastric cancer, cell lines and could be used to accurately detect and image intracellular miRs in an miR-specific manner. Furthermore, the relative levels of intracellular miRs in three different cell lines expressing miR-10b (high, moderate, and low levels) could be monitored using SGNP-MBs. Consequently, these results indicated that SGNP-MBs could have applications as highly potent, efficient nanoprobes to assess intracellular miR levels in living cells.</P>

Crystal Structures and Physical Properties of Ag(I) Coordination Polymers with Unsymmetrical Dipyridyl Ligand

Lee, Eunji,Ryu, Hyunsoo,Moon, Suk-Hee,Park, Ki-Min Korean Chemical Society 2013 Bulletin of the Korean Chemical Society Vol.34 No.11

Tubular Arrangement of 1,3-Alternate Calix[4]arene with Bipyridines: A Platform for [2 + 2] Photocyclization

Lee, Eunji,Ju, Huiyeong,Lee, Shim Sung,Park, Ki-Min American Chemical Society 2013 Crystal Growth & Design Vol.13 No.3

<P>By using a 1,3-alternate conformation of calix[4]arene tetrabenzoic acid (H<SUB>4</SUB>CTB), a pair of 4,4′-bipyridine has been aligned forming a cocrystallized one-dimensional tubular product <B>1</B>. Inspired by this result, the 1,3-alternate H<SUB>4</SUB>CTB has been utilized as “clips” to anchor the CC bond pairs of 4,4′-bipyridylethene to give an isotypical H-bonded tubular product <B>2</B> which undergoes the solid-state photodimerization.</P><P>By using a 1,3-alternate calix[4]arene tetrabenzoic acid (H<SUB>4</SUB>CTB), a pair of 4,4′-bipyridine and 4,4′-bipyridylethene was aligned forming cocrystallized one-dimensional tubular products, <B>1</B> and <B>2</B>, respectively, of which <B>2</B> undergoes the solid-state photodimerization.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/cgdefu/2013/cgdefu.2013.13.issue-3/cg301854f/production/images/medium/cg-2012-01854f_0006.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/cg301854f'>ACS Electronic Supporting Info</A></P>

Tube-Type Coordination Polymers: Two- and Four-Silver(I)-Mediated Linear Networking of Calix[4]arene Tetracarboxylates

Park, Ki-Min,Lee, Eunji,Park, Chul Soon,Lee, Shim Sung American Chemical Society 2011 Inorganic Chemistry Vol.50 No.23

<P>Two calix[4]arene tetracarboxylates, [calix[4]arene tetraacetate (K<SUB>4</SUB>CTA) and calix[4]arene tetrabenzoate (K<SUB>4</SUB>CTB)] as their potassium salts, have been prepared. Employing these as precursors, two Ag(I) coordination polymers incorporating calix[4]arene units have been successfully prepared and their X-ray crystal structures have been determined. In these, the CTA and CTB derivatives are linearly bound to two and four silver atoms, respectively, to generate unusual tubular nanostructures. A comparative NMR study was undertaken to investigate the nature of the metal ion blocking of the tube as observed in the CTA-derived structure. The thermal properties for both coordination polymers were also examined.</P><P>Assembly of calix[4]arene tetraacetate with silver(I) afforded a two-metal-mediated tube-type coordination polymer, but its interior is blocked by Ag<SUP>+</SUP> ions. By replacing the ligand with calix[4]arene tetrabenzoate, a four-metal-mediated coordination polymer with a perforated tubular structure was isolated.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/inocaj/2011/inocaj.2011.50.issue-23/ic201622p/production/images/medium/ic-2011-01622p_0001.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ic201622p'>ACS Electronic Supporting Info</A></P>

3D Metal–Organic Framework Based on a Lower-Rim Acid-Functionalized Calix[4]arene: Crystal-to-Crystal Transformation upon Lattice Solvent Removal

Lee, Eunji,Kim, Younghoon,Heo, Jungseok,Park, Ki-Min The American Chemical Society 2015 CRYSTAL GROWTH AND DESIGN Vol.15 No.8

<P>A rare. three-dimensional (3D) calix[4]arene-based metal organic framework (caliXMOF) {[Pb-2@L]center dot 2DMF}(n) (1) Was obtained by the solvothermal reaction,between a lower-rim acid: functionalized calix[4]arene (H4L) and Pb(NO3)(2) in N,N-dimethylformamide; 1 exhibited ths topology, in which Pb(II) atoms accommodate-a inside he calixarene unit adopted hemi-diretted coordination geometry. Interestingly; upon the removal Of guest solvent molecules, the 31) framework Of 1 readily converted to a shrunken 3D framework. [Pb2@L]0, (la) Via a single-crystal to single-crystal transformation. However, the resolvation of the guest molecules was not observed when 1a was immersed into DMF at room temperature or at 110 degrees C. Furthermore, la exhibited interesting CO2, sorption behavior: Its CO2 Isotherm curves exhibited looped patterns of linear adsorption and nonlinear photoluminescence properties of 1 and la were also reported.</P>

Anion-Directed Coordination Networks of a Flexible S-Pivot Ligand and Anion Exchange in the Solid State

Lee, Eunji,Ju, Huiyeong,Kim, Seulgi,Park, Ki-Min,Lee, Shim Sung The American Chemical Society 2015 CRYSTAL GROWTH AND DESIGN Vol.15 No.11

<P>Using an S-pivot joint flexible ligand bis(4-cyanobenzyl)sulfide (bcbs), three silver(I) complexes [Ag(bcbs)ClO<SUB>4</SUB>]<SUB><I>n</I></SUB> (<B>1</B>), [Ag<SUB>2</SUB>(bcbs) (CF<SUB>3</SUB>CO<SUB>2</SUB>)<SUB>2</SUB>]<SUB><I>n</I></SUB> (<B>2</B>), and {[Ag<SUB>3</SUB>(bcbs)<SUB>4</SUB>](PF<SUB>6</SUB>)<SUB>3</SUB>·4CH<SUB>2</SUB>Cl<SUB>2</SUB>}<SUB><I>n</I></SUB> (<B>3</B>) have been isolated. Configurations (“V”-, “L”-, and “W”-shapes) of the bcbs ligand in <B>1</B>–<B>3</B> can be tuned as a result of changing the anions of the silver(I) salts, which ultimately form a series of infinite low to high dimensional frameworks with different structures. The perchlorato compound <B>1</B> shows a stairway type 1-D ribbon structure, in which the anion acts as a monodentate terminal ligand. The bcbs ligand in <B>1</B> shows a gauche–anti arrangement, adopting an L-shape configuration. The π–π stacking interaction between adjacent ribbons in <B>1</B> yields a pseudo-2-D structure with a herringbone pattern. Compound <B>2</B> is composed of silver(I)–bcbs helical channels, which are further interlinked via monodentate bridging CF<SUB>3</SUB>CO<SUB>2</SUB><SUP>–</SUP> ions forming a 3-D multichannel framework with a <B>dmd</B> topology. Unlike <B>1</B>, the bcbs ligand in <B>2</B> shows an anti–anti arrangement, adopting a W-shape configuration. The corresponding PF<SUB>6</SUB><SUP>–</SUP> complex <B>3</B> exhibits a 2-fold interpenetrated 3-D framework. The preferred anion-free structure in <B>3</B> presumably reflects the strong coordination of the donor set and the weak affinity of the PF<SUB>6</SUB><SUP>–</SUP> toward the metal center. Similar to <B>1</B>, the bcbs ligand in <B>3</B> adopts an L-shape configuration. In this work, the structural variations of the resulting coordination polymers are mainly associated with the diverse configurations of the flexible ligand, as well as the different coordination modes and abilities for the anions. Anion exchange accompanying an irreversible structural conversion from <B>2</B> or <B>3</B> to <B>1</B> was monitored in the crystalline state by IR and PXRD studies. AFM images and height profiles for the crystal surface before and after the anion-exchange were observed. On the basis of the above measurements, a mechanistic process from the 3-D structured <B>3</B> (PF<SUB>6</SUB><SUP>–</SUP> form) to the 1-D structured <B>1</B> (ClO<SUB>4</SUB><SUP>–</SUP> form) by the anion exchange was also proposed.</P><P>An anion effect on the silver(I) coordination networks with a flexible ligand and their anion-exchange which shows a perchlorate selectivity are reported.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/cgdefu/2015/cgdefu.2015.15.issue-11/acs.cgd.5b01050/production/images/medium/cg-2015-01050x_0001.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/cg5b01050'>ACS Electronic Supporting Info</A></P>

Coordination Networks of a Ditopic Macrocycle Exhibiting Anion-Controlled Dimensional Changes and Crystal-to-Crystal Anion Exchange

Lee, Eunji,Park, Ki-Min,Ikeda, Mari,Kuwahara, Shunsuke,Habata, Yoichi,Lee, Shim Sung American Chemical Society 2015 Inorganic Chemistry Vol.54 No.11

<P>A rationally designed NO<SUB>2</SUB>S<SUB>2</SUB>-donor macrocycle <B>L</B> was synthesized, and anion variation (PF<SUB>6</SUB><SUP>–</SUP>, CF<SUB>3</SUB>CO<SUB>2</SUB><SUP>–</SUP>, NO<SUB>3</SUB><SUP>–</SUP>, and CF<SUB>3</SUB>SO<SUB>3</SUB><SUP>–</SUP>) of its silver(I) complexes was employed as a strategy for controlling their coordination modes and network dimensions. The assembly reactions of <B>L</B> with four silver(I) salts afforded the complexes [Ag<SUB>2</SUB><B>L</B><SUB>2</SUB>](PF<SUB>6</SUB>)<SUB>2</SUB> (<B>1</B>), [Ag<SUB>4</SUB><B>L</B><SUB>2</SUB>(CF<SUB>3</SUB>CO<SUB>2</SUB>)<SUB>4</SUB>]<SUB><I>n</I></SUB> (<B>2</B>), [Ag<SUB>4</SUB><B>L</B><SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>4</SUB>]<SUB><I>n</I></SUB> (<B>3</B>), and {[Ag<SUB>3</SUB><B>L</B><SUB>2</SUB>(CF<SUB>3</SUB>SO<SUB>3</SUB>)<SUB>2</SUB>]CF<SUB>3</SUB>SO<SUB>3</SUB>}<SUB><I>n</I></SUB> (<B>4</B>) that adopt cyclic dimer, 1D, 2D, and pseudo 3D network structures, respectively, with the structure adopted depending on the coordination ability and coordination modes of the anion used. Interestingly, quantitative anion exchange accompanying an irreversible structural conversion from <B>2</B>, <B>3</B>, or <B>4</B> to <B>1</B> was observed in the crystalline state by powder X-ray diffraction (PXRD) and IR spectroscopy. A stepwise mechanistic process from <B>2</B> (CF<SUB>3</SUB>CO<SUB>2</SUB><SUP>–</SUP>, 1D) to <B>3</B> (NO<SUB>3</SUB><SUP>–</SUP>, 2D) by anion exchange was also proposed.</P><P>Depending on the anions (CF<SUB>3</SUB>CO<SUB>2</SUB><SUP>−</SUP> and NO<SUB>3</SUB><SUP>−</SUP>) used in silver(I) complexations with a ditopic macrocycle, 1D and 2D polymeric products were isolated, respectively. The observed anion exchange of CF<SUB>3</SUB>CO<SUB>2</SUB><SUP>−</SUP> in the former with NO<SUB>3</SUB><SUP>−</SUP> is noteworthy because it is undergone quantitatively in the crystalline state, accompanying the dimensional increase from 1D to 2D.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/inocaj/2015/inocaj.2015.54.issue-11/acs.inorgchem.5b00422/production/images/medium/ic-2015-004222_0017.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ic5b00422'>ACS Electronic Supporting Info</A></P>

Development of a cost-effective CO₂ adsorbent from petroleum coke via KOH activation

Jang, Eunji,Choi, Seung Wan,Hong, Seok-Min,Shin, Sangcheol,Lee, Ki Bong Elsevier 2018 APPLIED SURFACE SCIENCE - Vol.429 No.-

<P><B>Abstract</B></P> <P>The capture of CO<SUB>2</SUB> via adsorption is considered an effective technology for decreasing global warming issues; hence, adsorbents for CO<SUB>2</SUB> capture have been actively developed. Taking into account cost-effectiveness and environmental concerns, the development of CO<SUB>2</SUB> adsorbents from waste materials is attracting considerable attention. In this study, petroleum coke (PC), which is the carbon residue remaining after heavy oil upgrading, was used to produce high-value-added porous carbon for CO<SUB>2</SUB> capture. Porous carbon materials were prepared by KOH activation using different weight ratios of KOH/PC (1:1, 2:1, 3:1, and 4:1) and activation temperatures (600, 700, and 800°C). The specific surface area and total pore volume of resulting porous carbon materials increased with KOH amount, reaching up to 2433m<SUP>2</SUP>/g and 1.11cm<SUP>3</SUP>/g, respectively. The sample prepared under moderate conditions with a KOH/PC weight ratio of 2:1 and activation temperature of 700°C exhibited the highest CO<SUB>2</SUB> adsorption uptake of 3.68mmol/g at 25°C and 1bar. Interestingly, CO<SUB>2</SUB> adsorption uptake was linearly correlated with the volume of micropores less than 0.8nm, indicating that narrow micropore volume is crucial for CO<SUB>2</SUB> adsorption. The prepared porous carbon materials also exhibited good selectivity for CO<SUB>2</SUB> over N<SUB>2</SUB>, rapid adsorption, facile regeneration, and stable adsorption–desorption cyclic performance, demonstrating potential as a candidate for CO<SUB>2</SUB> capture.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Cost effective CO<SUB>2</SUB> adsorbent could be prepared from petroleum coke. </LI> <LI> CO<SUB>2</SUB> uptakes have good correlation with narrow micropores (<0.8nm). </LI> <LI> The prepared microporous carbon showed excellent CO<SUB>2</SUB> adsorption performance. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>