An acidic pH-triggered polymeric micelle for dual-modality MR and optical imaging

Gao, GuangHui,Heo, Hyejung,Lee, JungHee,Lee, DooSung Royal Society of Chemistry 2010 Journal of materials chemistry Vol.20 No.26

<P>A dual-modality imaging probe was developed for magnetic resonance imaging (MRI) and optical imaging, based on a Fe<SUB>3</SUB>O<SUB>4</SUB>-encapsulated pH-responsive block copolymer, which was conjugated with a red fluorescent dye Sulforhodamine 101 (SR101). The block copolymer, containing methoxy poly(ethylene glycol) (PEG) as a hydrophilic segment and poly(β-amino ester) (PAE) with ionizable tertiary amine groups on its backbone as a pH-responsive segment, can be dissolved in response to an acidic pH environment, or form self-assembled micelles in aqueous media at the physiological pH (∼pH 7.4) due to the hydrophobic deionized PAE segment acting as a micellar core. The polymeric micelle conjugated with SR101 was found to have a red-fluorescent emission at 612 nm, a sharp pH transition of pH 6.8–7.0, indicating that it can be an ideal pH-triggered carrier in response to the acidic biological environment. Subsequently, the Fe<SUB>3</SUB>O<SUB>4</SUB>-encapsulated micelle was evaluated by dynamic light scattering (DLS), cryogenic transmission electron microscope (cryo-TEM), and pH-dependent Fe<SUB>3</SUB>O<SUB>4</SUB> release. The confocal laser scanning microscopy (CLSM) observation demonstrated the cellular uptake of SR101-labeled polymeric micelles by breast cancer cells.</P> <P>Graphic Abstract</P><P>A facile and powerful acidic pH-triggered Fe<SUB>3</SUB>O<SUB>4</SUB>-encapsulated polymeric micelle conjugated with a fluorescent dye for dual-modality MRI and optical imaging. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c0jm00317d'> </P>

Sterically hindered amine-functionalized MCM-41 composite for efficient carbon dioxide capture

Fei Gao,Cailin Ji,Shougui Wang,Weiwen Wang,Jipeng Dong,Changqing Guo,Yuwen Gao,Guanghui Chen 한국화학공학회 2022 Korean Journal of Chemical Engineering Vol.39 No.8

A new adsorbent based on sterically hindered amine for efficient CO2 capture was prepared. Mesoporoussilicon MCM-41 was modified by sterically hindered amine AMPD (2-amino-2-methyl-1,3-propanediol) in differentAMPD loadings by a facile solid-state self-assembly approach. The physicochemical properties of the MCM-41@AMPDcomposites were analyzed using XRD, BET, FT-IR and SEM, and the composites were investigated for the CO2 captureperformance, including CO2 capture capacity, adsorption selectivity and cycling stability. Characterization analysesshowed that the AMPD active components were successfully incorporated and well dispersed into the mesoporous siliconMCM-41 surfaces. Adsorption results suggest that the modification by the active ingredient AMPD can significantlyimprove the CO2 capture performance. The MCM-41@AMPD material with an AMPD loading of 7mmol∙g1MCM-41 support exhibits a good CO2 adsorption capacity and CO2 adsorption selectivity, and shows excellent cyclingstability. Furthermore, the isosteric heat of CO2 adsorption on the MCM-41@AMPD-7 material was evaluated by theClausius-Clapeyron equation, and the value was 34-78 kJ∙mol1.

Facile fabrication of copper oxide modified activated carbon composite for efficient CO2 adsorption

Guanghui Chen,Fei Wang,Shougui Wang,Cailin Ji,Weiwen Wang,Jipeng Dong,Fei Gao 한국화학공학회 2021 Korean Journal of Chemical Engineering Vol.38 No.1

Copper oxide modified activated carbon (CuO/AC) composites for the CO2 capture were synthesized via a facile assembly strategy associated with a direct solid-state heat dispersion process by introducing CuO into AC using Cu(NO3)2 as the copper source. The synthesized CuO/AC composites with various CuO contents were characterized by powder X-ray diffraction, scanning electron microscopy and nitrogen adsorption-desorption measurement, and the CO2 adsorption performance was investigated. The characterization results indicate that the Cu(NO3)2 species was well dispersed into the AC pore channels and then converted to a highly dispersed CuO after the activation process. The adsorption results reveal that the CO2 adsorption performance can be significantly improved by introducing CuO onto the AC surfaces, and the CuO(0.6)/AC composite with a CuO loading of 0.6mmol/g AC shows a high CO2 adsorption capacity and adsorption selectivity and displays an excellent reversibility. Additionally, the calculated adsorption heat values of CO2 on the CuO(0.6)/AC composite are in the range of 27.3 to 33.9 kJ/mol.

Experimental studies of bubble cutting in a lab-scale micro-structured bubble column with different liquid viscosity

Guanghui Chen,Zhongcheng Zhang,Fei Gao,Jianlong Li,Jipeng Dong 한국화학공학회 2022 Korean Journal of Chemical Engineering Vol.39 No.8

Bubble cutting was realized by installing a wire mesh in a micro-structured bubble column (MSBC) andstudied experimentally with liquid viscosity range from 1 to 39.6mPa·s. A non-intrusive high-speed camera methodwas used to determine bubble size and size distribution. The changes of gas holdup, bubble size, size distribution andSauter mean diameter before and after cutting were systematically studied with mesh openings of 3.8mm and 5.5mm. Three novel bubble cutting behaviors with uniform cutting, detachment cutting and indirect cutting behavior wereobserved. In the presence of two wire meshes, the bubble size distribution roughly shows a Gaussian curve distributionand the peak tends to shift towards lower diameters. With increasing liquid viscosity and superficial gas velocity,the dominant peak tends to move towards higher diameters, resulting in poor mesh cutting effect. After cutting, in thecase of two wire meshes, the Sauter mean diameter decreased by 33.5% and 22.2% and the gas holdup increased by3.2-12.2% and 1.2-4.4%, respectively. For the case of 3.8 mm mesh opening, the interfacial area increased by 10-26%,which is much better than 5.5mm mesh. The mean bubble size above the mesh will grow again and its growth ratedepends on the liquid viscosity.

Dissolution of synthetic U-DBP and corrosion of stainless steel by dissolution schemes

Wang Guanghui,Li Yaorui,He Mingjian,Zhang Meng,Gao Yang,He Hui,Jiao Caishan 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.5

In spent fuel reprocessing, UO2(DBP)2 (U-DBP) can be deposited in stainless steel equipment. U-DBP must be removed by dissolution and the process must not cause corrosion to stainless steel. This study was conducted to find the best scheme for dissolution. U-DBP was manufactured by the titrimetric sedimentation method. The effects of different factors on the dissolution of U-DBP were investigated. For example, solid-liquid ratio, hydrazine carbonate solutions with different mass components, mixed solutions containing different concentrations of H2O2, and different carbonates. The results indicated that U-DBP does not have a regular crystal morphology. With the increase of the solid-liquid ratio and the mass fraction of hydrazine carbonate, the concentration of U(VI) at the dissolution equilibrium increases gradually. The addition of H2O2 has a great promotion effect on the dissolution. However, when the concentration of H2O2 is greater than 0.5 M, the dissolution solution may have an erosive effect on the stainless steel. (NH4)2CO3 can increase the dissolution capacity of dissolved U-DBP, but it may also accelerate the corrosion of stainless steel.

The Effects of Continuous Cabbage Cropping on Soil Microbial Communities Structure

Yu Gao,Guanghui Xu 한국토양비료학회 2014 한국토양비료학회 학술발표회 초록집 Vol.2014 No.6

Bioinspired Nucleobase-driven Adhesive, Tough and Conductive Hydrogels for Underwater Sensing

Xin Liu,Qin Zhang,Guanghui Gao 한국고분자학회 2019 한국고분자학회 학술대회 연구논문 초록집 Vol.44 No.2

China Consensus Document on Allergy Diagnostics

Chen Hao,Li Jing,Cheng Lei,Gao Zhongshan,Lin Xiaoping,Zhu Rongfei,Yang Lin,Tao Ailin,Hong Haiyu,Tang Wei,Guo Yinshi,Huang Huaiqiu,Sun Jinlyu,Lai He,Lei Cheng,Liu Guanghui,Xiang Li,Chen Zhuanggui,Ma Ha 대한천식알레르기학회 2021 Allergy, Asthma & Immunology Research Vol.13 No.2

The prevalence of allergic diseases has increased dramatically in recent years in China, affecting the quality of life in 40% of the population. The identification of allergens is the key to the diagnosis of allergic diseases. Presently, several methods of allergy diagnostics are available in China, but they have not been standardized. Additionally, cross-sensitization and co-sensitization make allergy diagnostics even more complicated. Based on 4 aspects of allergic disease (mechanism, diagnosis procedures, allergen detection in vivo and in vitro as well as the distribution map of the most important airborne allergens in China) and by referring to the consensus of the European Society of Allergy and Clinical Immunology, the World Allergy Organization, and the important literature on allergy diagnostics in China in recent years, we drafted this consensus of allergy diagnostics with Chinese characteristics. It aims to standardize the diagnostic methods of allergens and provides a reference for health care givers. The current document was prepared by a panel of experts from the main stream of professional allergy associations in China.

Highly sensitive and wearable gel-based sensors with a dynamic physically cross-linked structure for strain-stimulus detection over a wide temperature range

Xia, Shan,Song, Shixin,Li, Yi,Gao, Guanghui The Royal Society of Chemistry 2019 Journal of Materials Chemistry C Vol.7 No.36

<P>Traditional hydrogel sensors can only be applicable in a limited temperature range, such as ambient temperature, since water is easily frozen or evaporated under extreme conditions, which seriously affects their practical application. Here, a highly sensitive wearable strain sensor is fabricated from a flexible, self-healing, anti-freezing and anti-drying gel with a physical cross-linking structure, which is composed of polyacrylic acid, chitosan, and graphene oxide in a mixed solvent of water and glycerol. The dynamic cross-linking enables the network structure and ion channels of the gel to be rapidly recovered and reconstituted, thereby allowing the gel-based strain sensor to display excellent stretchability (more than 1000%) and outstanding sensing performance with a rapid response time of 40 ms, and remarkable repeatability and stability. As a result, the gel can be applied as an epidermal strain sensor for real-time detection of human motions, including joint motions, speaking and breathing. Moreover, the gel can maintain excellent flexibility, stretchability and conductivity over a wide temperature range from −20 °C to 70 °C, which effectively improves the practicality and durability of the gel in practical applications. Therefore, such flexible, conductive, anti-freezing and anti-drying gel may have promising applications in the field of wearable devices, soft robot systems and other applications that need to be applied under changeable conditions.</P>