Selective Oxidative Degradation of Organic Pollutants by Singlet Oxygen-Mediated Photosensitization: Tin Porphyrin versus C₆₀ Aminofullerene Systems

Kim, Heechan,Kim, Wooyul,Mackeyev, Yuri,Lee, Gi-Seon,Kim, Hee-Joon,Tachikawa, Takashi,Hong, Seokwon,Lee, Sanghyup,Kim, Jungbae,Wilson, Lon J.,Majima, Tetsuro,Alvarez, Pedro J. J.,Choi, Wonyong,Lee, Ja American Chemical Society 2012 Environmental science & technology Vol.46 No.17

<P>This study evaluates the potential application of tin porphyrin- and C<SUB>60</SUB> aminofullerene-derivatized silica (SnP/silica and aminoC<SUB>60</SUB>/silica) as <SUP>1</SUP>O<SUB>2</SUB> generating systems for photochemical degradation of organic pollutants. Photosensitized <SUP>1</SUP>O<SUB>2</SUB> production with SnP/silica, which was faster than with aminoC<SUB>60</SUB>/silica, effectively oxidized a variety of pharmaceuticals. Significant degradation of pharmaceuticals in the presence of the 400-nm UV cutoff filter corroborated visible light activation of both photosensitizers. Whereas the efficacy of aminoC<SUB>60</SUB>/silica for <SUP>1</SUP>O<SUB>2</SUB> production drastically decreased under irradiation with λ > 550 nm, Q-band absorption caused negligible loss of the photosensitizing activity of SnP/silica in the long wavelength region. Faster destruction of phenolates by SnP/silica and aminoC<SUB>60</SUB>/silica under alkaline pH conditions further implicated <SUP>1</SUP>O<SUB>2</SUB> involvement in the oxidative degradation. Direct charge transfer mediated by SnP, which was inferred from nanosecond laser flash photolysis, induced significant degradation of neutral phenols under high power light irradiation. Self-sensitized destruction caused gradual activity loss of SnP/silica in reuse tests unlike aminoC<SUB>60</SUB>/silica. The kinetic comparison of SnP/silica and TiO<SUB>2</SUB> photocatalyst in real wastewater effluents showed that photosensitized singlet oxygenation of pharmaceuticals was still efficiently achieved in the presence of background organic matters, while significant interference was observed for photocatalyzed oxidation involving non-selective OH radical.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/esthag/2012/esthag.2012.46.issue-17/es301775k/production/images/medium/es-2012-01775k_0009.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/es301775k'>ACS Electronic Supporting Info</A></P>

Magnetic mesoporous materials for removal of environmental wastes

Kim, Byoung Chan,Lee, Jinwoo,Um, Wooyong,Kim, Jaeyun,Joo, Jin,Lee, Jin Hyung,Kwak, Ja Hun,Kim, Jae Hyun,Lee, Changha,Lee, Hongshin,Addleman, R. Shane,Hyeon, Taeghwan,Gu, Man Bock,Kim, Jungbae Elsevier 2011 Journal of hazardous materials Vol.192 No.3

<P><B>Highlights</B></P><P>• Iron oxide particle embedded mesoporous silica and carbon are synthesized. • Both mesoporous materials are separated easily under aqueous condition using magnet. • Mercury or fluorescein is removed by using magnetic mesoporous material. • Tyrosinase is immobilized in magnetic mesoporous silica and reused after reaction. • Magnetic mesoporous materials are applicable to removal of environmental wastes.</P> <P><B>Abstract</B></P><P>We have synthesized two different magnetic mesoporous materials that can be easily separated from aqueous solutions by applying a magnetic field. Synthesized magnetic mesoporous materials, Mag-SBA-15 (magnetic ordered mesoporous silica) and Mag-OMC (magnetic ordered mesoporous carbon), have a high loading capacity of contaminants due to high surface area of the supports and high magnetic activity due to the embedded iron oxide particles. Application of surface-modified Mag-SBA-15 was investigated for the collection of mercury from water. The mercury adsorption using Mag-SBA-15 was rapid during the initial contact time and reached a steady-state condition, with an uptake of approximately 97% after 7h. Application of Mag-OMC for collection of organics from water, using fluorescein as an easily trackable model analyte, was explored. The fluorescein was absorbed into Mag-OMC within minutes and the fluorescent intensity of solution was completely disappeared after an hour. In another application, Mag-SBA-15 was used as a host of tyrosinase, and employed as recyclable catalytic scaffolds for tyrosinase-catalyzed biodegradation of catechol. Crosslinked tyrosinase in Mag-SBA-15, prepared in a two step process of tyrosinase adsorption and crosslinking, was stable enough for catechol degradation with no serious loss of enzyme activity. Considering these results of cleaning up water from toxic inorganic and organic contaminants, magnetic mesoporous materials have a great potential to be employed for the removal of environmental contaminants and potentially for the application in large-scale wastewater treatment plants.</P>

Quantitative analysis of individual magnetic nanowires based on wide-field diamond magnetometry

Jungbae Yoon,Junhwan Moon,Jugyeong Jeong,Yujin Kim,Youngkeun Kim,Donghun Lee 한국자기학회 2022 한국자기학회 학술연구발표회 논문개요집 Vol.31 No.2

Single Step Isolation and Activation of Primary CD3⁺ T Lymphocytes Using Alcohol-Dispersed Electrospun Magnetic Nanofibers

Kim, Kwanghee,An, Hyo Jin,Jun, Seung-Hyun,Kim, Tae-Jin,Lim, Seon Ah,Park, Gayoung,Na, Hyon Bin,Park, Yong Il,Hyeon, Taeghwan,Yee, Cassian,Bluestone, Jeffrey A,Kim, Jungbae,Lee, Kyung-Mi American Chemical Society 2012 NANO LETTERS Vol.12 No.8

<P>Electrospun polymer nanofibers with entrapped magnetic nanoparticles (magnetic NP–NF) represent a novel scaffold substrate that can be functionalized for single-step isolation and activation of specific lymphocyte subsets. Using a surface-embedded T cell receptor ligand/trigger (anti-CD3 monoclonal antibody), we demonstrate, as proof of principle, the use of magnetic NP–NF to specifically isolate, enrich, and activate CD3<SUP>+</SUP> T cells from a heterogeneous cell mixture, leading to preferential expansion of CD8<SUP>+</SUP>CD3<SUP>+</SUP> T cells. The large surface area, adjustable antibody density, and embedded paramagnetic properties of the NP–NF permitted enhanced activation and expansion; its use represents a strategy that is amenable to an efficient selection process for adoptive cellular therapy as well as for the isolation of other cellular subsets for downstream translational applications.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/nalefd/2012/nalefd.2012.12.issue-8/nl301388d/production/images/medium/nl-2012-01388d_0007.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nl301388d'>ACS Electronic Supporting Info</A></P>

Biocatalytic membrane with acylase stabilized on intact carbon nanotubes for effective antifouling via quorum quenching

Kim, Tae Hee,Lee, Inseon,Yeon, Kyung-Min,Kim, Jungbae Elsevier 2018 Journal of membrane science Vol.554 No.-

<P><B>Abstract</B></P> <P>This study developed biocatalytic membranes that can effectively control the surface biofouling based on the enzymatic quenching of bacterial quorum sensing. Acylase (AC) was immobilized and stabilized on intact carbon nanotubes (CNTs) via enzyme adsorption, precipitation, and crosslinking (EAPC) method, maintaining 66% of its initial enzyme activity for 200 days under rigorous shaking (200 rpm). This highly stable EAPC was anchored on the polyvinylidene fluoride (PVDF) microfilter using polydopamine coatings (EAPC membrane). The antifouling performance and mechanism of EAPC membrane was intensively evaluated under static incubation with a model bacterium of <I>Pseudomonas aeruginosa</I>. When compared with the PVDF membranes with and without free AC, the EAPC membrane enhanced the water permeability by 5-folds at an optimum loading of 0.40 g-CNTs/m<SUP>2</SUP> by effectively inhibiting the biofilm formation. The EAPC membrane with this optimal CNT loading did not increase the hydraulic resistance of membrane itself. In the lab-scale continuous filtrations, the EAPC membrane with its loading of 0.40 g-CNTs/m<SUP>2</SUP> demonstrated 1.6-fold delay of trans-membrane pressure increase compared to the PVDF membrane. It is anticipated that biocatalytic membrane based on quorum quenching nanobiocatalysis has a great potential in antifouling applications without changing the process configuration or additional treatments.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Enzyme adsorption, precipitation and crosslinking (EAPC) for immobilization on CNTs. </LI> <LI> Quorum quenching EAPC was attached on PVDF membrane via polydopamine coatings. </LI> <LI> EAPC membranes inhibited biofilm formation and enhanced water permeability. </LI> <LI> EAPC membranes showed antifouling with no need of additional treatments. </LI> </UL> </P>

Nanobiocatalysis for CO₂ Conversion and Utilization

Jungbae KIM 한국생물공학회 2021 한국생물공학회 학술대회 Vol.2021 No.4

Even though enzymes can be employed and newly proposed for various applications such as electrochemical biosensors, membrane antifouling and CO2 conversion, their successes in practical applications are often hampered due to their poor stability. Nanobiocatalysis, immobilizing enzymes using various nanomaterials, has demonstrated its successes in stabilizing the enzyme activity for various enzyme applications such as biosensors, biofuel cells, enzyme-linked immunosorbent assay, membrane antifouling, and CO2 conversion. This presentation will mainly cover nanobiocatalytic stabilization of carbonic anhydrases for their potential successes in CO2 conversion. Especially, the nanobiocatalytic stabilization of carbonic anhydrase, catalyzing the hydration of CO2 to bicarbonate at a 10^5-6 turnover number, has made an unprecedented success by maintaining 83% of initial enzyme activity after incubation in aqueous solution under shaking at 200 rpm for two years. Stabilized carbonic anhydrase was successfully employed for the effective conversion of CO2 to bicarbonate, which was further used for expedited microalgae growth and improved calcium carbonate production. If time permits, several other examples of nanobiocatalytic applications together with several other research areas will be introduced.

Selective Killing of Pathogenic Bacteria by Antimicrobial Silver Nanoparticle-Cell Wall Binding Domain Conjugates

Kim, Domyoung,Kwon, Seok-Joon,Wu, Xia,Sauve, Jessica,Lee, Inseon,Nam, Jahyun,Kim, Jungbae,Dordick, Jonathan S. American Chemical Society 2018 ACS APPLIED MATERIALS & INTERFACES Vol.10 No.16

<P>Broad-spectrum antibiotics indiscriminately kill bacteria, removing nonpathogenic microorganisms and leading to evolution of antibiotic resistant strains. Specific antimicrobials that could selectively kill pathogenic bacteria without targeting other bacteria in the natural microbial community or microbiome may be able to address this concern. In this work, we demonstrate that silver nanoparticles, suitably conjugated to a selective cell wall binding domain (CBD), can efficiently target and selectively kill bacteria. As a relevant example, CBD<SUP>BA</SUP> from <I>Bacillus anthracis</I> selectively bound to <I>B. anthracis</I> in a mixture with <I>Bacillus subtilis</I>, as well in a mixture with <I>Staphylococcus aureus</I>. This new biologically-assisted hybrid strategy, therefore, has the potential to provide selective decontamination of pathogenic bacteria with minimal impact on normal microflora.</P> [FIG OMISSION]</BR>

Nano-Biotechnology in Using Enzymes for Environmental Remediation

( Jungbae Kim ) 한국공업화학회 2003 한국공업화학회 연구논문 초록집 Vol.2003 No.-

Nanoimmobilization of marine epoxide hydrolase of Mugil cephalus for repetitive enantioselective resolution of racemic styrene oxide in aqueous buffer.

Kim, Young Hyun,Lee, Inseon,Choi, Sung Hee,Lee, Ok Kyung,Kim, Jungbae,Lee, Eun Yeol American Scientific Publishers 2013 Journal of Nanoscience and Nanotechnology Vol.13 No.3

<P>We developed two nanoimmobilized biocatalyst systems of thermally unstable Mugil cephalus epoxide hydrolase (McEH) for enantioselective resolution of racemic styrene oxide in aqueous buffer. The recombinant and purified McEH enzyme was immobilized onto magnetic nanoparticles (Mag-NPs) via a two step process of enzyme precipitation and crosslinking. McEH enzyme was also adsorbed, precipitated, and cross-linked in/on polyaniline nanofibers (PANFs). The residual relative activity of free McEH, defined as the ratio of residual activity to the initial activity, was 8% after incubation at 30 degrees C for 80 h while those of McEH immobilized onto Mag-NPs and in/on PANFs were 15% and 33% in the same condition, respectively. McEH immobilizations onto Mag-NPs and in/on PANFs could be reused in seven repetitive batch reactions for enantioselective hydrolysis of racemic styrene oxide to prepare (S)-styrene oxide with 98% enantiomeric excess (ee) while retaining greater than 40-50% of their initial activity.</P>

Nanobiocatalysis for protein digestion in proteomic analysis

Kim, Jungbae,Kim, Byoung Chan,Lopez-Ferrer, Daniel,Petritis, Konstantinos,Smith, Richard D. WILEY-VCH Verlag 2010 Proteomics Vol.10 No.4

<P>The process of protein digestion is a critical step for successful protein identification in bottom-up proteomic analyses. To substitute the present practice of in-solution protein digestion, which is long, tedious, and difficult to automate, many efforts have been dedicated for the development of a rapid, recyclable and automated digestion system. Recent advances of nanobiocatalytic approaches have improved the performance of protein digestion by using various nanomaterials such as nanoporous materials, magnetic nanoparticles, and polymer nanofibers. Especially, the unprecedented success of trypsin stabilization in the form of trypsin-coated nanofibers, showing no activity decrease under repeated uses for 1 year and retaining good resistance to proteolysis, has demonstrated its great potential to be employed in the development of automated, high-throughput, and on-line digestion systems. This review discusses recent developments of nanobiocatalytic approaches for the improved performance of protein digestion in speed, detection sensitivity, recyclability, and trypsin stability. In addition, we also introduce approaches for protein digestion under unconventional energy input for protein denaturation and the development of microfluidic enzyme reactors that can benefit from recent successes of these nanobiocatalytic approaches.</P>