Ratiometric fluorescent probe based on symmetric peptidyl receptor with picomolar affinity for Zn²⁺ in aqueous solution

Mehta, Pramod Kumar,Oh, Eun-Taex,Park, Heon Joo,Lee, Keun-Hyeung Elsevier 2017 Sensors and actuators. B Chemical Vol.245 No.-

<P><B>Abstract</B></P> <P>It is still a significant challenge to synthesize ratiometric fluorescent probes based on the new receptor with potent and tunable binding affinities for Zn<SUP>2+</SUP>. A fluorescent probe (<B>1</B>) based on the symmetric peptide receptor bearing two imidazole and two sulfonamide groups was synthesized for the ratiometric detection of Zn<SUP>2+</SUP> in aqueous solution. <B>1</B> selectively and sensitively detected Zn<SUP>2+</SUP> among biological relevant metal ions by a ratiometric response. Upon addition of Zn<SUP>2+</SUP>, monomer emissions of the pyrenes at 379 and 399nm increased significantly and the excimer emission at 508nm decreased with a blue shift. About 1 equiv of Zn<SUP>2+</SUP> ions completely induced the ratiometric response of <B>1</B>. Job’s plot analysis indicated that <B>1</B> formed a 1:1 complex with Zn<SUP>2+</SUP>. The dissociation constant for Zn<SUP>2+</SUP> was found to be 300 pM. The binding mode study revealed that two imidazole and two sulfonamide groups of the peptide receptor played an important role in the binding with Zn<SUP>2+</SUP>. The peptidyl probe successfully penetrated and detected intracellular Zn<SUP>2+</SUP> in live cells.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The fluorescent probe based on the peptide receptor with tunable binding affinities for Zn<SUP>2+</SUP>. </LI> <LI> Highly sensitive ratiometric response to Zn<SUP>2+</SUP> in aqueous solutions at physiological pH. </LI> <LI> A picomolar binding affinity (300 pM) for Zn<SUP>2+</SUP> in aqueous solutions and formation of a 1:1 complex. </LI> <LI> Highly selective response to Zn<SUP>2+</SUP> among various biological relevant metal ions. </LI> <LI> Cell penetration and detection of intracellular Zn<SUP>2+</SUP> in live cells. </LI> </UL> </P>

Zn/Zn-Mg 이중 층 박막의 밀착력 향상을 위한 Zn interlayer 미세구조 제어에 관한 연구

이승환,김회근,송면규,김정완,이상율 대한금속·재료학회 2019 대한금속·재료학회지 Vol.57 No.11

In this study, the microstructure-controlled Zn interlayers were synthesized to improve the adhesion strength of Zn/Zn-Mg double layer coatings. The coating chamber temperature and working pressure were controlled based on the Structure Zone Model principles, to obtain a dense columnar microstructure in the Zn interlayer. By controlling the coating chamber temperature, however, porous nanowire structures resulted in an increasing chamber temperature over 100 °C, suggesting that it was not possible to obtain a columnar microstructure of the Zn interlayer. On the other hand, it was possible to synthesize a dense columnar structure in the Zn interlayer by controlling the working pressure. Furthermore, by decreasing the working pressure during deposition, the density of Zn interlayer increased from 79.1% to 93.6%. A lap shear test was performed to evaluate the adhesion strength, and the adhesion strength of Zn /Zn-Mg double layer coatings increased from 20.38 MPa to 24.48 MPa as the density of the Zn interlayer increased. These adhesion strength results were higher than those of the commercial galvanized steels, suggesting that an additional improvement in the adhesion strength would be possible by controlling the microstructure of the Zn interlayer in the Zn/Zn-Mg double layer coatings.

Zn₃(PO₄)₂ Protective Layer on Zn Anode for Improved Electro-chemical Properties in Aqueous Zn-ion Batteries

Chae-won Kim,Junghee Choi,Jin-Hyeok Choi,Ji-Youn Seo,Gumjae Park The Korean Electrochemical Society 2023 Journal of electrochemical science and technology Vol.14 No.2

Aqueous zinc-ion batteries are considered as promising alternatives to lithium-ion batteries for energy storage owing to their safety and cost efficiency. However, their lifespan is limited by the irreversibility of Zn anodes because of Zn dendrite growth and side reactions such as the hydrogen evolution reaction and corrosion during cycling. Herein, we present a strategy to restrict direct contact between the Zn anode and aqueous electrolyte by fabricating a protective layer on the surface of Zn foil via phosphidation method. The Zn₃(PO₄)₂ protective layer effectively suppresses Zn dendrite growth and side reactions in aqueous electrolytes. The electrochemical properties of the Zn₃(PO₄)₂@Zn anode, such as the overpotential, linear polarization resistance, and hydrogen generation reaction, indicate that the protective layer can suppress interfacial corrosion and improve the electrochemical stability compared to that of bare Zn by preventing direct contact between the electrolyte and the active sites of Zn. Remarkably, MnO₂ Zn₃(PO₄)₂@Zn exhibited enhanced reversibility owing to the formation a stable porous layer, which effectively inhibited vertical dendrite growth by inducing the uniform plating of Zn²⁺ ions underneath the formed layer.

진공증착법에 의한 p-Zn0.51Cd0.49Se 박막의 성장 및 물리적 특성의 온도의존성

한동헌,윤은정,이정주,강광용 한국물리학회 2015 새물리 Vol.65 No.8

Zn0.51Cd0.49Se thin films with thicknesses of about 430 nm were deposited on indium-tin-oxide (ITO)-coated glass substrates by using thermal evaporation of high-purity ZnSe and CdSe mixed tablets in high vacuum. X-ray diffraction spectra showed that the Zn0.51Cd0.49Se thin films had mixed ZnSe and CdSe cubic zincblende structures with a lattice constant a = 6.077 °A and that the crystals were preferentially grown with a (111) orientation. From the results of X-ray photoelectron spectroscopy, the intensities of the binding energies of the Zn 2p core levels were found to be increased with increasing annealing temperature and those of the Cd 3d and the Se 3d core levels to be decreased. The optical energy band gap of the as-deposited Zn0.51Cd0.49Se thin film was 2.32 eV. Especially, the optical energy band gaps of Zn0.51Cd0.49Se thin films annealed in a vacuum electric furnace at temperatures from 200 ℃ to 500 ℃ were about 2.30 eV ~ 2.08 eV. From measurements of the photoinduced discharge characteristics, the hole drifts in the Zn0.51Cd0.49Se thin films and the hole concentrations were found to increase with increasing annealing temperature but the hole mobilities were found to decrease. 진공증착법으로 ITO (indium-tin-oxide) 기판 위에 두께 약 430 nm의 Zn0.51Cd0.49Se 박막을 제작하였다. X-선 회절 분석에 의하여 Zn0.51Cd0.49Se 박막은 CdSe와 ZnSe가 혼합된 정육면체 섬아연광 구조를 하고 있었으며, 그 성장방향은 (111) 방향으로 우선 성장하였다. X-선 광전자 분광 결과로부터, 열처리 온도 증가에 따라 Zn 2p에 대한 결합에너지의 피크 적분 강도는 증가하고, Cd 3d와 Se 3d에 대한 결합에너지의 피크 적분 강도는 감소하였다. 증착된 Zn0.51Cd0.49Se 박막의 광학적인 에너지 띠 간격은 2.32 eV이었다. 특히, 200 ℃ ~ 500 ℃로 진공 열처리한 박막의 광학적 에너지 띠 간격은 2.30 eV ~ 2.08 eV이었다. 광유기 방전 특성으로 분석한 Zn0.51Cd0.49Se 박막은 p-형 (양공표류)이며, 열처리 온도 증가에 따라 양공의 이동도는 감소하고, 양공의 농도는 증가함을 보였다.

분무열분해법으로 성장된 In2O3:Zn 박막의 구조와 광학적 전기적 특성

서동주 한국물리학회 2008 새물리 Vol.56 No.5

In$_2$O$_3$:Zn films were deposited on glass substrates by using spray pyrolysis. The crystal structures of the In$_2$O$_3$:Zn films prepared with Zn concentrations up to 10 wt\% were identified as Zn-doped In$_2$O$_3$ (In$_2$O$_3$:Zn) with the preferred (222) orientation of a cubic structure. There were no new compounds in the In$_2$O$_3$:Zn. The optical transmission of the samples deposited with various Zn concentrations were about 80 $\sim$ 95 \% in the wavelength range from 400 to 1200 nm. The optical energy band gap of the In$_2$O$_3$:Zn films deposited with a Zn concentration of 0 wt\% was 3.656 eV. The optical energy band gaps of the In$_2$O$_3$:Zn films decreased with increasing Zn concentration. The sheet resistivity, the carrier concentration, the Hall coefficient, and the mobility of the In$_2$O$_3$:Zn films deposited with a Zn concentration of 7 wt\% were 13.6 $k\Omega/\square$, 5.68 $\times$ 10$^{18}$cm$^{-3}$, 109.86 m$^2$/C, and 13.97 cm$^2$/V$\cdot$s respectively. In$_2$O$_3$:Zn 박막을 분무열분해법으로 유리기판 위에 성장시켰다. Zn를 0 $\sim$ 10 wt\%까지 첨가하여 성장시킨 In$_2$O$_3$:Zn 박막의 결정구조는 입방구조이며, (222)면이 뚜렷하게 성장된 Zn이 불순물로 첨가된 In$_2$O$_3$ (In$_2$O$_3$:Zn) 박막으로 확인되었다. In$_2$O$_3$:Zn 박막의 광학적 투과율은 400 $\sim$ 1200 nm 영역에서 80 $\sim$ 95 \%이었다. Zn을 0 wt\% 첨가하여 성장시킨 In$_2$O$_3$:Zn 박막의 광학적 에너지 띠간격은 3.656 eV이었고, In$_2$O$_3$:Zn 박막의 광학적 에너지 띠간격은 Zn의 농도가 증가함에 따라 감소하였다. Zn를 7 wt\% 첨가하여 성장시킨 시료의 경우 p-형 전도성이 다른 시료보다 좋았는데, 이 시료의 면저항, 운반자농도, 홀계수, 이동도는 각각 13.6 $k\Omega/\square$, 5.68 $\times$ 10$^{18}$cm$^{-3}$, 109.86 m$^2$/C, 13.97 cm$^2$/V$\cdot$s이었다.

알칼리 침전제에 의해 제조된 아연 중간생성물 및 산화아연 결정화

장대환,김보람,김대원,Jang, Dae-Hwan,Kim, Bo-Ram,Kim, Dae-Weon 한국결정성장학회 2021 韓國結晶成長學會誌 Vol.31 No.6

ZnO는 출발물질인 황산아연과 알칼리 침전제인 NaOH와 Na₂CO₃에 의해 생성된 아연 중간생성물의 변이 거동과 결정화 조건에 따라 제조하였다. ZnO 결정화를 위해 아연 중간생성물인 Zn₄(OH)₆SO₄·H₂O, Zn₅(OH)₆(CO₃)₂·H₂O를 각각 400℃, 800℃에서 1시간 하소하였고, 하소 온도는 열중량 분석을 기반으로 하였다. 아연 중간생성물인 Zn₄(OH)₆SO₄·H₂O은 400℃에서 Zn₄(OH)₆SO₄·H₂O, ZnO 결정상이 혼재됨을 확인하였고, 800℃에서 완전히 열분해되어 순수한 ZnO만 형성되었다. Na₂CO₃와 반응하여 생성된 아연 중간생성물인 Zn₅(OH)₆(CO₃)₂·H₂O는 400℃ 이상에서 완전한 ZnO의 결정상을 확인하였다. Na₂CO₃와 반응을 통해 상대적으로 낮은 하소 온도에서 나노 입자의 ZnO를 합성할 수 있었다. ZnO was synthesized according to the transformation behavior and crystallization conditions of Zn-intermediate obtained by zinc sulfate as a precursor and NaOH, Na₂CO₃ as a alkali agents. For ZnO crystallization, Zn₄(OH)₆SO₄·H₂O and Zn₅(OH)₆(CO₃)₂·H₂O as a Zn-intermediate were calcined at 400℃ and 800℃ for 1 h, respectively, based on decomposition temperature from TGA. Zn₄(OH)₆SO₄·H₂O was confirmed to have mixed Zn₄(OH)₆SO₄·H₂O and ZnO at 400℃, and was completely thermally decomposed at 800℃ to form ZnO phase. The prepared Zn₅(OH)₆(CO₃)₂·H₂O as a Zn-intermediate by the reaction with Na₂CO₃ was transformed to a complete ZnO crystallization over 400℃. Nano-sized ZnO can be synthesized at a relatively lower calcination temperature through the reaction with Na₂CO₃.

Zn ion의 영향에 따른 $(Y,\;Zn)_2O_3$:$Eu^{3+}$ 적색 형광체의 발광특성

송영현,문지욱,박우정,윤대호,Song, Y.H.,Moon, J.W.,Park, W.J.,Yoon, D.H. 한국결정성장학회 2008 한국결정성장학회지 Vol.18 No.6

본 연구에서는 자외선 영역에서 발광하는 우수한 특성의 적색 형광체를 얻기 위하여 고상 반응법으로 air 분위기에서 $1200^{\circ}C$에서 6시간 동안 열처리하여 $(Y,\;Zn)_2O_3$:$Eu^{3+}$를 Zn 이온의 농도 변화에 따라 실험하였다. $(Y,\;Zn)_2O_3$:$Eu^{3+}$를 XRD에 의해 비교 분석한 결과 주요 peak들이 JCPDS card(No. 41-1105)와 거의 일치하는 것을 확인하였다. 그러나 Zn 이온치 농도가 5 mol% 이상일 때 XRD에서 ZnO의 peak이 관찰되는 것을 확인 하였다. 이로 인하여 Zn 이온의 농도가 5 mol% 이하일 때 불순물 상 없이 $Y_2O_3$ 구조에 잘 고용되는 것을 확인하였다. $(Y,\;Zn)_2O_3$:$Eu^{3+}$의 발광 peak은 여기 흡수 영역인 ${\lambda}ex=254\;nm$를 기준으로 612 nm 영역에서 $Eu^{3+}$ 이온의 $^5D_0{\rightarrow}^7F_2$에 전형적인 에너지 천이에 의해 가장 강한 발광 peak을 나타내는 것을 확인하였으나 Zn 이온의 농도가 10 mo1% 이상일 때 갑자기 발광 peak이 현저히 감소하는 것을 확인하였고 최대의 발광 peak을 가질 때 형광체의 조성은 $(Y_{0.95},\;Zn_{0.05})_2O_3$:$Eu^{3+}_{0.075}$이였고 입자 size는 $0.4{\sim}3{\mu}m$로 확인되었다. To enhance the luminescence properties, the red phosphor composed of $(Y,\;Zn)_2O_3$:$Eu^{3+}$ as doping concentration of Zn ion is synthesized at $1200^{\circ}C$ for 6 hrs in air atmosphere by conventional solid reaction method. As a result of the red phosphor $(Y,\;Zn)_2O_3$:$Eu^{3+}$ is measured X-ray diffraction (XRD), The main peak is nearly corresponded to the same as JCPDS card (No. 41-1105). When the doping concentration of Zn ion is more than 5 mol%, However, the ZnO peak is showed by XRD analysis. Therefore, when the doping concentration of Zn ion is less than 5 mol%, the Zn ion is well mixed in $Y_2O_3$ structure without the impurity phases. The photoluminescence (PL) properties is shown as this phosphor is excited in 254 nm region and the highest emission spectra of $(Y,\;Zn)_2O_3$:$Eu^{3+}$ has shown in 612 nm region because of a typical energy transition ($^5D_0{\rightarrow}^7F_2$) of $Eu^{3+}$ ion. As the doping concentration of Zn ion is more than 10 mol%, the emission peak is suddenly decreased. when the highest emission peak as doping concentration of Zn ion is shown, the composition of this phosphor is $(Y_{0.95},\;Zn_{0.05})_2O_3$:$Eu^{3+}_{0.075}$ and the particle size analyzed by FE-SEM is confirmed from 0.4 to $3{\mu}m$.

두꺼비 배아를 활용한 화학물질의 독성평가 연구

고선근 한국환경생태학회 2016 한국환경생태학회지 Vol.30 No.4

국내에 서식하는 두꺼비의 배아를 이용하여 화학물질의 독성평가에 대한 가능성을 파악하기 위해 FETAX(Frog Embryo Teratogenesis Assay-Xenopus) 기법에 따라 두꺼비(Bufo gargarizans)의 배아를 배양하면서 Zn과 Benomyl의 효과를 probit 분석법으로 조사하였다. 그 결과, Zn과 Benomyl의 농도에 의존하여 유생의 체장 길이는 감소하고 치사율 과 기형율은 증가하였으며 Zn과 Benomyl의 teratogenic concentration(EC50)은 각각 2.3, 1.0㎎/ℓ을 나타내었고 embryo lethal concentrations(LC50)은 10.3, 6.9㎎/ℓ을 나타내었다. Teratogenic index(TI=LC50/EC50)는 Zn의 경우 4.4, Benomyl의 경우 6.7을 나타내어 Zn과 Benomyl은 두꺼비 배아 발달에 최기형성 물질로 작용함을 알 수 있었다. 이상의 결과들로 보아 Zn과 Benomyl 모두 낮은 농도에서 두꺼비 배아발달에 민감하게 반응하였다. 이는 다량의 배아 확보가 가능하며 배양이 용이하고 치사율, 기형율, 성장률, 기형양상 등을 기존의 연구들과 비교하였을 때 유사한 결과를 나타내어 두꺼비 배아를 활용한 시험기법은 화학물질 및 환경오염물질의 독성검정에 활용할 수 있을 것으로 판단된다. In this experiment, embryos of Asian toad, Bufo gargarizans, were investigated to evaluate toxicity of chemicals along FETAX(Frog Embryo Teratogenesis Assay-Xenopus) protocol. Asian toad, Bufo gargarizans, embryos incubated and investigation of Zn and Benomyl effect by probit analysis. As a result, depends on the concentrations of Zn and Benomyl, mortality and malformation rates were increases and larval body length were decreased. The teratogenic concentration(EC50) of Zn and Benomyl were 2.3, 1.0mg/ℓ, respectively and the embryo lethal concentration(LC50) Zn and Benomyl were 10.3, 6.9, respectively. The teratogenic index(TI) were 4.4 in Zn and 6.7 in Benomyl, thus showed teratogenicity in embryonic development of B. gargarizans. These results reveal that Zn and Benomyl in this experiment suppressed the development of embryos at relatively low concentration. Much of B. gargarizans embryos can be secured, and easy to incubate. In addition, mortality, malformation ratios, malformation patterns and growth rates are similar to the results from the other assay systems. Therefore, the B. gargarizans embryo teratogenesis assay system could be a useful tool to evaluate toxicity of pollutants in environment.

Effects of Annealing Heat Treatment on the Corrosion Resistance of Zn/Mg/Zn Multilayer Coatings

배기태,라정현,이인규,이상율,남경훈 대한금속·재료학회 2017 METALS AND MATERIALS International Vol.23 No.3

Zn coatings alloyed with magnesium offer superior corrosion resistance compared to pure Zn or other Zn-basedalloy coatings. In this study, Zn/Mg/Zn multilayer coatings with various Mg layer thicknesses were synthesizedusing an unbalanced magnetron sputtering process and were annealed to form Zn-Mg intermetallic phases. Theeffects of the annealing heat treatment on the corrosion resistance of the Zn/Mg/Zn multilayer coatings wereevaluated using electrochemical measurements. The extensive diffusion of magnesium species into the upperand lower zinc layer from the magnesium layer in the middle of the coating was observed after the heattreatment. This phenomenon caused (a) the porous microstructure to transition into a dense structure and (b) theformation of a MgZn2 intermetallic phase. The results of the electrochemical measurements demonstratedthat the heat treated Zn/Mg/Zn multilayer coatings possessed higher levels of corrosion resistance than thenon-heat treated coatings. A Zn/Mg/Zn multilayer coating with MgZn2 and (Zn) phases showed the best corrosionresistance among the heat treated coatings, which could be attributed to the reduced galvanic corrosioneffects due to a small potential gradient between the MgZn2 and zinc.

꿩의 생산성 향상을 위한 인공점등과 사료개선 : Ⅲ. Zinc 및 Manganese의 보충급여가 정강이, 우모 및 성장에 미치는 효과

김규일,양영훈 濟州大學校 農科大學 動物科學硏究所 1993 動物科學論叢 Vol.8 No.1

The objective of this study was to improve pheasant starter diet by supplementing with zinc and manga-nese. A commercial starter diet, which contained 40.5±0.3 mg Zn, and 60.7±0.9 mg Mn/kg, was used as a basal diet. Zinc carbonate and manganese chloride were added to the basal diet: I) No supplement (control), 2) 100mg Zn/kg Zn/kg diet(Zn group), 3) 100 mg Mn/kg diet (Mn group) and 4) 100 mg Zn + 100mg Mn/kg diet(Zn+Mn group). A total of 420(4 treatments X 3 replications X 35 birds) 3day-old chicks was fed the experimental diets until 4 weeks of age. No sign of perosis(Mn deficiency) was found in any diet groups. Shank length at 4 weeks of age was significantly(p<0.05) different between Mn(46.8 mm) and Zn(44.3 mm) groups. and between Mn(46.8 mm) and Zn+Mn (44.4 mm) groups, but was not different between Mn and control(45.2 mm) groups. Mean feather length of Mn(7.6 cm) group was highest among the four groups. Significant(p<O.OS) defferences in feather length were found between Mn(7.6 cm) and Zn(7.2 cm) groups. and between the controI(7.6 cm) and Ln groups. Percentage of feather fraying, which is the main syndrome of zinc deficiency, was in the iange of 1.8(Zn group)-4.3%(control). but the difference was not significant(p> 0.05). Average daily gain of the control. Zn, Mn and Zn+Mn groups was 2.5, 2.4. 2.8 and 2.5 g. respectively. and the difference was signilicant(p<0.05) between Mn and Zn groups. Feed/gain ratio of the control. Zn. Mn and Zn+Mn group was 3.8, 3.9. 4.2 and 4.3. respectively(p>0.05). Results indicate that zinc and manp-anese contents(Zn. 40.5±0.3 pug; Mn, 60.7±0.9 pg/g diet) in the commercial chick diet are sufficient to meet the Zn and Mn requirements for growth and normal feathering for pheasant chicks. Mn supplementation seemed favorable for daily gain, feed efficiency. feather length and shank length as compared to the control.