CO2 분리를 위한 PEGDA/PETEDA dendrimer 막의 제조

한나,이현경 한국막학회 2013 멤브레인 Vol.23 No.1

PEGDA/PETEDA dendrimer 막은 PEGDA에 5~15 wt%의 PETEDA dendrimer를 첨가하고 UV를 조사하여 제조하였다. 제조된 막의 특성은 FT-IR, 1H-NMR 그리고 DSC를 통해 분석하였다. PEGDA/PETEDA dendrimer 막의 유리전이온도(Tg)는 PETEDA dendrimer의 함량이 증가할수록 감소하였다. CH4에 대한 CO2 투과 특성은 PETEDA dendrimer의 함량과 압력을 변화시키며 조사하였다. 10 wt%의 PETEDA dendrimer를 포함하는 막의 투과도는 162.2 barrer였으나 CO2/CH4 이상분리 인자는 31.8로 가장 높게 나타났다. PEGDA/PETEDA dendrimer composite membranes was prepared by UV photopolymerizing of poly ethylene glycol diacrylate (PEGDA) containing 5~15 wt% pentaerythrityl tetraethylenediamine (PETEDA) dendrimer. The prepared composite membrane was characterized by FT-IR, 1H-NMR and DSC. The glass transition temperature (Tg) of PEGDA/PETEDA dendrimer composite decreased with the increment of PETEDA dendrimer content. The CO2 separation properties over CH4 were investigated by changing the PETEDA dendrimer content and pressure. The composite membrane containing 10 wt% PETEDA dendrimer exhibited on excellent CO2/CH4 ideal selectivity of 31.8 and a CO2 permeability of 162.2 barrer.

A mechanistic investigation of highly stable nano ZrO₂ decorated nitrogen-rich azacytosine tethered graphene oxide-based dendrimer for the removal of arsenite from water

Prabhu, Subbaiah Muthu,Pawar, Radheshyam Rama,Sasaki, Keiko,Park, Chang Min Elsevier 2019 CHEMICAL ENGINEERING JOURNAL -LAUSANNE- Vol.370 No.-

<P><B>Abstract</B></P> <P>We focused to synthesize graphene oxide-polyamidoamine dendrimer, up to 2nd generation, (GO-gen2) <I>via</I> a grafting method and the tethered groups were further covalently functionalized with a nitrogen-rich of an aromatic triazine ring of 5-azacytosine (Aza). Zirconia nanoparticles (ZrO<SUB>2</SUB>) has been identified as promising material for removal of AsO<SUB>3</SUB> <SUP>3−</SUP> from water, however, its practical applicability is hindered due to its nanosize. Hence, ZrO<SUB>2</SUB> was successfully decorated through biomolecule assist on GO-gen2-Aza dendrimer. Various amounts of GO-gen2-Aza were used as stable supports to develop the nanocomposites with ZrO<SUB>2</SUB>. Then, the adsorption efficiency of highly toxic AsO<SUB>3</SUB> <SUP>3−</SUP> on developed composites was investigated for water treatment. The synthesized GO-dendrimer composites were characterized well before and after adsorption of AsO<SUB>3</SUB> <SUP>3−</SUP> using FTIR, PXRD, SEM, XPS, TGA, TEM and BET analysis. Particle size distribution of ZrO<SUB>2</SUB> revealed the peak top at 28 nm by zeta potential measurement. During synthesis, the GO sheets of composite were laminated by incorporation of ZrO<SUB>2</SUB> nanoparticles. The results of the batch experiments showed that ZrO<SUB>2</SUB>@2%GO-gen2-Aza dendrimer had higher adsorption density of AsO<SUB>3</SUB> <SUP>3−</SUP> than that of other developed forms of dendrimer composites. Langmuir equation well described the adsorption isotherm with the maximum adsorption capacity of 1.075 mmol/g. In addition, the enhanced AsO<SUB>3</SUB> <SUP>3−</SUP> adsorption density on ZrO<SUB>2</SUB> surface of ZrO<SUB>2</SUB>@x%GO-gen2-Aza, in which the GO-sheets were delaminated, resulting more ZrO<SUB>2</SUB> was dispersed homogeneously in the GO-sheets for maximum uptake of AsO<SUB>3</SUB> <SUP>3−</SUP> from water, confirmed by PXRD patterns. These results suggested that the developed GO-based dendrimer materials can be utilised for the practical remediation of toxic AsO<SUB>3</SUB> <SUP>3−</SUP> and other similar types of toxic ions, selenite, phosphate and fluoride from the contaminated water.</P> <P><B>Highlights</B></P> <P> <UL> <LI> ZrO<SUB>2</SUB> entrapped GO-based Aza-tethered PAMAM dendrimer composite is prepared. </LI> <LI> Ligand exchange is likely responsible for the adsorption of AsO<SUB>3</SUB> <SUP>3−</SUP>. </LI> <LI> The lamination/delamination chemistry of GO-dendrimer composite are expressed. </LI> <LI> Maximum adsorption capacity of 1.075 mmol/g was achieved for AsO<SUB>3</SUB> <SUP>3−</SUP>. </LI> <LI> Selectivity and reusability test (4 cycles) did not affect the efficiency of AsO<SUB>3</SUB> <SUP>3−</SUP>. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Modulation of Electroosmotic Flow through Skin: Effect of Poly(Amidoamine) Dendrimers

( Hye Ji Kim ),( Seaung Youl Oh ) 한국응용약물학회 2018 Biomolecules & Therapeutics(구 응용약물학회지) Vol.26 No.2

The objective of this work is to evaluate the effect of polyamidoamine (PAMAM) dendrimers on electroosmotic flow (EOF) through skin. The effect of size and concentration of dendrimer was studied, using generation 1, 4 and 7 dendrimer (G1, G4 and G7, respectively). As a marker molecule for the direction and magnitude of EOF, a neutral molecule, acetoaminophen (AAP) was used. The visualization of dendrimer permeation into the current conducting pore (CCP) of skin was made using G4-fluorescein isothiocyanate (FITC) conjugate and confocal microscopy. Without dendrimer, anodal flux of AAP was much higher than cathodal or passive flux. When G1 dendrimer was added, anodal flux decreased, presumably due to the decrease in EOF by the association of G1 dendrimer with net negative charge in CCP. As the generation increased, larger decrease in anodal flux was observed, and the direction of EOF was reversed. Small amount of methanol used for the preparation of dendrimer solution also contributed to the decrease in anodal flux of AAP. Cross-sectional view perpendicular to the skin surface by confocal laser scanning microscope (CLSM) study showed that G4 dendrimer-FITC conjugate (G4-FITC) can penetrate into the viable epidermis and dermis under anodal current. The permeation route seemed to be localized on hair follicle region. These results suggest that PAMAM dendrimers can permeate into CCP and change the magnitude and direction of EOF. Overall, we obtained a better understanding on the mechanistic insights into the electroosmosis phenomena and its role on flux during iontophoresis.

Modulation of Electroosmotic Flow through Skin: Effect of Poly(Amidoamine) Dendrimers

김혜지,오승열 한국응용약물학회 2018 Biomolecules & Therapeutics(구 응용약물학회지) Vol.26 No.2

The objective of this work is to evaluate the effect of polyamidoamine (PAMAM) dendrimers on electroosmotic flow (EOF) through skin. The effect of size and concentration of dendrimer was studied, using generation 1, 4 and 7 dendrimer (G1, G4 and G7, respectively). As a marker molecule for the direction and magnitude of EOF, a neutral molecule, acetoaminophen (AAP) was used. The visualization of dendrimer permeation into the current conducting pore (CCP) of skin was made using G4–fluorescein isothiocyanate (FITC) conjugate and confocal microscopy. Without dendrimer, anodal flux of AAP was much higher than cathodal or passive flux. When G1 dendrimer was added, anodal flux decreased, presumably due to the decrease in EOF by the association of G1 dendrimer with net negative charge in CCP. As the generation increased, larger decrease in anodal flux was observed, and the direction of EOF was reversed. Small amount of methanol used for the preparation of dendrimer solution also contributed to the decrease in anodal flux of AAP. Cross-sectional view perpendicular to the skin surface by confocal laser scanning microscope (CLSM) study showed that G4 dendrimer-FITC conjugate (G4-FITC) can penetrate into the viable epidermis and dermis under anodal current. The permeation route seemed to be localized on hair follicle region. These results suggest that PAMAM dendrimers can permeate into CCP and change the magnitude and direction of EOF. Overall, we obtained a better understanding on the mechanistic insights into the electroosmosis phenomena and its role on flux during iontophoresis.

Modulation of Electroosmotic Flow through Skin: Effect of Poly(Amidoamine) Dendrimers

Kim, Hye Ji,Oh, Seaung Youl The Korean Society of Applied Pharmacology 2018 Biomolecules & Therapeutics(구 응용약물학회지) Vol.26 No.2

The objective of this work is to evaluate the effect of polyamidoamine (PAMAM) dendrimers on electroosmotic flow (EOF) through skin. The effect of size and concentration of dendrimer was studied, using generation 1, 4 and 7 dendrimer (G1, G4 and G7, respectively). As a marker molecule for the direction and magnitude of EOF, a neutral molecule, acetoaminophen (AAP) was used. The visualization of dendrimer permeation into the current conducting pore (CCP) of skin was made using G4-fluorescein isothiocyanate (FITC) conjugate and confocal microscopy. Without dendrimer, anodal flux of AAP was much higher than cathodal or passive flux. When G1 dendrimer was added, anodal flux decreased, presumably due to the decrease in EOF by the association of G1 dendrimer with net negative charge in CCP. As the generation increased, larger decrease in anodal flux was observed, and the direction of EOF was reversed. Small amount of methanol used for the preparation of dendrimer solution also contributed to the decrease in anodal flux of AAP. Cross-sectional view perpendicular to the skin surface by confocal laser scanning microscope (CLSM) study showed that G4 dendrimer-FITC conjugate (G4-FITC) can penetrate into the viable epidermis and dermis under anodal current. The permeation route seemed to be localized on hair follicle region. These results suggest that PAMAM dendrimers can permeate into CCP and change the magnitude and direction of EOF. Overall, we obtained a better understanding on the mechanistic insights into the electroosmosis phenomena and its role on flux during iontophoresis.

The role of terminal groups in dendrimer systems for the treatment of organic contaminants in aqueous environments

Han, Ye-Lim,Kim, So-Yeon,Kim, Taejin,Kim, Ki-Hyun,Park, Jae-Woo Elsevier 2020 JOURNAL OF CLEANER PRODUCTION Vol.250 No.-

<P><B>Abstract</B></P> <P>A typical water treatment process consists of a physical, biological, or chemical route or a combination of these options. However, the use of conventional techniques has been challenged due to the diversification of waterborne pollutants. In response, various nanomaterials with advanced functions have been developed to provide effective remediation options. Among such materials, dendrimers have received attention due to their enhanced treatment capacities and multifunctional structures formed by the modification of terminal groups. This review offers comprehensive insight into dendrimers with respect to their practical applications. In particular, we focus on the interactions between dendrimer terminal groups and contaminants in relation to their structures to meaningfully describe the associated mechanisms. To meet this goal, the performances of dendrimers and their composites were evaluated in terms of partition coefficient (PC) values. Accordingly, the best results were observed for chitosan grafted PPI dendrimers (e.g., 6214 mg/g·μM against reactive black 5). Finally, we also addressed the present limitations of dendrimer technology and their prospects in water treatment.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Dendrimers are hyperbranched polymers containing core, branch, and terminal groups. </LI> <LI> Dendrimers are potential nanomaterials for water treatment. </LI> <LI> Dendrimer properties can be controlled by various terminal groups. </LI> <LI> Water-contaminant removal mechanisms according to terminal groups are presented. </LI> <LI> Contaminant removal efficiency is enhanced by use and combination of dendrimers. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Balb/c 마우스에서 Keyhole limpet hemocyanine (KLH)의 항원성에 대한 PAMAM dendrimer 의 면역증강 효과

이가영(Ga-Young Lee),김민지(Min Jee Kim),김소연(So Yeon Kim),이경복(Kyung Bok Lee),오동현(Dong Hyun Oh),조영호(Young Ho Cho),유영춘(Yung Choon Yoo) 한국생명과학회 2020 생명과학회지 Vol.30 No.10

본 연구에서는 Keyhole limpet hemocyanin (KLH)에 대한 체액성 및 세포성 면역반응 유도에 대한 PAMAM dendrimer G4 (PAMAM)의 증강 효과를 조사하였다. PAMAM을 KLH와 2주 간격으로 2회 피하주사로 면역한 후, KLH에 대한 특이항체를 측정한 결과, KLH+PAMAM 면역 그룹은 KLH만을 단독으로 면역한 그룹에 약 30배 이상 높은 유의한 항체가(IgG+IgA+IgM) 상승을 나타냈다. ELISA 분석에 의해 KLH 특이적인 면역글로부린의 isotype을 측정한 결과, PAMAM를 혼합하여 면역함으로서 IgG1, IgG2a, IgG2b, IgG3 및 IgM 항체의 역가가 유의하게 증가하는 것으로 확인되었다. 또한 면역 개시 7주째에 면역동물에 KLH 항원을 피하주사하고 swelling reaction을 통해 세포성 면역반응인 지연형 과민반응(DTH)을 측정한 결과, KLH+PAMAM으로 면역한 그룹에서 KLH만을 단독으로 면역한 그룹에 비해 높은 DTH 유도활성이 관찰되었다. 한편 면역동물의 비장세포를 취하여 in vitro에서 KLH로 재자극한 후 림프구 증식반응과 사이토카인 유도활성을 측정한 결과, PAMAM을 혼합하여 면역한 그룹에서 KLH 단독 면역 그룹에 비해 림프구의 증식반응에 유의하게 증가하였으며, Th1 type (IFN-γ)과 Th2 type (IL-4) 사이토카인의 생성도 모두 상승하는 것으로 확인되었다. 이상의 결과로부터 PAMAM dendrimer는 함께 투여된 항원물질에 의해 유도되는 세포성 면역과 체액성 면역을 상승시키는 활성이 있는 것으로 확인되었으며, 이는 PAMAM dendrimer가 면역 adjuvant로서 응용 가능한 소재임을 입증하는 것이다. The adjuvant effect of PAMAM dendrimer G4 (PAMAM) on the induction of humoral and cellular immune responses against keyhole limpet hemocyanin (KLH) was examined. Mice were immunized subcutaneously twice at two-week intervals with KLH, with or without PAMAM dendrimer (100 μg/mouse), and the mice immunized with KLH+PAMAM showed significantly higher antibody titers against KLH than those immunized with KLH alone. The assay for determining the isotypes of the antibodies showed that PAMAM augmented the KLH-specific antibody titers of IgG1, IgG2a, IgG2b, IgG3, and IgM. In addition, mice immunized twice with KLH+PAMAM followed by a subcutaneous injection of KLH (20 μg/site) 7 weeks after the primary immunization exhibited a higher delayed-type hypersensitivity (DTH) reaction than those treated with KLH alone. In an in vitro analysis of T lymphocyte proliferation in response to KLH in week 8, the splenocytes of mice treated with KLH+ PAMAM showed significantly higher proliferating activity than those treated with KLH alone, and the culture supernatants of cell cultures from mice immunized with added PAMAM dendrimer showed higher levels of KLH-specific cytokine (IL-4 and IFN-r) production. These results suggest that PAMAM dendrimer G4 possesses a potent immune-adjuvant activity for enhancing both humoral and cell-mediated immunity specific to foreign antigens.

Gadobutrol-dendrimer effects on metastatic and apoptotic gene expression

Kebriaezadeh, Abbas,Ashrafi, Sepehr,Rasouli, Rahimeh,Ebrahimi, Seyed Esmaeil Sadat,Hamedani, Morteza Pirali,Assadi, Artin,Saffari, Mostafa,Ardestani, Mehdi Shafiee Techno-Press 2016 Advances in nano research Vol.4 No.2

Dendrimers are one of the most appropriate nanocaries for imaging moieties in imaging applications.The purpose of this study was the evalution of cytotoxicity and inducing apoptosis of dendrimers. This study was conducted in order to investigate the metastasis suppression effect of dendrimer in human breast MCF-7 cell line and finding the nanoparticle protein corona in biological enviromental. Dendrimer cytotoxicity effect was assessed by MTT assay. The mRNA experession level of KAI1 as a metastasis suppressor gene, Bax as Pro- apoptotic gene, Bcl-2 as an anti-apoptotic gene and GAPDH as a housekepping gene were determined by real-time PCR assays.concentration-dependent nanoparticle cytotoxicity effect was proofed at range of 1-2 mg/mL in 24 hours, significant upregulation of mRNA expression of Bax, was observed whereas expression of anti-apoptotic Bcl-2 was down-regulated, also expression of metastasis suppressor gene KAI1 was up-regulated. So far a few studies confirmed apoptosis enhancement effect of dendrimers in MCF-7 cell line via bax/bcl-2 pathways. dendrimer nanoparticles was able to act as metastase inhibitor via upregulation of KAI1 gene.

Recent progress in dendrimer-based nanomedicine development

김예진,박은지,나동희 대한약학회 2018 Archives of Pharmacal Research Vol.41 No.6

Dendrimers offer well-defined nanoarchitectureswith spherical shape, high degree of molecular uniformity,and multiple surface functionalities. Such unique structuralproperties of dendrimers have created many applicationsfor drug and gene delivery, nanomedicine, diagnostics, andbiomedical engineering. Dendrimers are not only capableof delivering drugs or diagnostic agents to desired sites byencapsulating or conjugating them to the periphery, butalso have therapeutic efficacy in their own. When comparedto traditional polymers for drug delivery, dendrimershave distinct advantages, such as high drug-loadingcapacity at the surface terminal for conjugation or interiorspace for encapsulation, size control with well-definednumbers of peripheries, and multivalency for conjugationto drugs, targeting moieties, molecular sensors, andbiopolymers. This review focuses on recent applications ofdendrimers for the development of dendrimer-basednanomedicines for cancer, inflammation, and viral infection. Although dendrimer-based nanomedicines still facesome challenges including scale-up production and wellcharacterization,several dendrimer-based drug candidatesare expected to enter clinical development phase in thenear future.

Dendrimer-Capped Gold Nanoparticles for Highly Reliable and Robust Surface Enhanced Raman Scattering

Kim, Kwanghyun,Lee, Jeongyeop,Jo, Gyeongcheon,Shin, Seungmin,Kim, Jin-Baek,Jang, Ji-Hyun American Chemical Society 2016 ACS APPLIED MATERIALS & INTERFACES Vol.8 No.31

<P>Dendrimer-stabilized gold nanoparticles (Au-Den) were prepared by a facile solution based method for a highly reliable and robust surface enhanced Raman scattering (SERS) substrate. Au-Den was selectively attached on the surface of reduced graphene oxide (rGO) by noncovalent interactions between the Au capping dendrimer and the graphene surface. Au-Den/rGO exhibits the outstandingly stable and highly magnified Raman signal with an enhancement factor (EF) of 3.9 X 10(7) that enables detection of R6G dyes with concentration as low as 10 nM, retaining 95% of the Raman signal intensity after 1 year. The remarkable stability and enhancement originated not only from a simple combination of the electromagnetic and chemical mechanism of SERS but also from intensified packing density of stable Au Den on the graphene substrate due to the firm binding between the dendrimer capped metal nanoparticles and the graphene substrate. This method is not limited to the gold nanoparticles and G4 dendrimer used herein, but also can be applied to other dendrimers and metal nanoparticles, which makes the material platform suggested here superior to other SERS substrates.</P>