Publications by authors named "Xiaobang Hou"

5 Publications

  • Page 1 of 1

Controlled Release of Agrochemicals Using pH and Redox Dual-Responsive Cellulose Nanogels.

J Agric Food Chem 2019 Jun 5;67(24):6700-6707. Epub 2019 Jun 5.

Department of Environmental Engineering , North China Electric Power University , 689 Huadian Road , Baoding , Hebei 071003 , P. R. China.

A novel pH and redox dual-responsive cellulose-based nanogel was prepared for the controlled release of agrochemicals. To synthesize the responsive nanogel, palmitoyl chloride and glyoxal were modified on carboxymethyl cellulose sequentially and 3,3'-dithiobis(propionohydrazide) was used as a cross-linker to assemble the nanogel. The morphology, structure, and physical properties of nanogels were characterized with transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), particle size analysis, and zeta-potential measurement. Facing pH and redox stimulation, the nanogel showed reversible sol-gel transitions, indicating good pH- and redox-responsiveness. The nanogel loaded with agrochemicals exhibited high loading capacity and various release behaviors. In addition, the experiment of nanogel on heavy metal ions complexation displayed the potential of improving soil condition while delivering agrochemicals.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.jafc.9b00536DOI Listing
June 2019

Preparation of Novel Nano-Sized Hydrogel Microcapsules via Layer-By-Layer Assembly as Delivery Vehicles for Drugs onto Hygiene Paper.

Polymers (Basel) 2018 Mar 19;10(3). Epub 2018 Mar 19.

State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China.

Hydrogel microcapsules are improved transplantation delivery vehicles for pharmaceuticals by effectively segregating the active ingredients from the surroundings and delivering them to a certain target site. Layer-by-layer (LbL) assembly is an attractive process to fabricate the nano-sized hydrogel microcapsules. In this study, nano-sized hydrogel microcapsules were prepared through LbL assembly using calcium carbonate nanoparticles (CaCO₃ NPs) as the sacrificial inorganic template, sodium alginate (SA) and polyethyleneimine (PEI) as the shell materials. Ciprofloxacin was used to study the encapsulation and release properties of the hydrogel microcapsules. The hydrogel microcapsules were further adsorbed onto the paper to render antimicrobial properties. The results showed that the mean size of the CaCO₃ template was reduced after dispersing into sodium -dodecyl sulfate (SDS) solution under sonication. Transmission electron microscope (TEM) and atomic force microscope (AFM) revealed that some hydrogel microcapsules had a diameter under 200 nm, typical creases and collapses were found on the surface. The nano-sized PEI/SA hydrogel microcapsules showed high loading capacity of ciprofloxacin and a sustained release. PEI/SA hydrogel microcapsules rendered good antimicrobial properties onto the paper by the adsorption of hydrogel microcapsules, however, the mechanical properties of the hygiene paper were decreased.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/polym10030335DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6414901PMC
March 2018

Immobilizing Laccase on Modified Cellulose/CF Beads to Degrade Chlorinated Biphenyl in Wastewater.

Polymers (Basel) 2018 Jul 19;10(7). Epub 2018 Jul 19.

Department of Chemical Engineering, University of New Brunswick, Fredericton, NB E3B 5A3, Canada.

Novel modified cellulose/cellulose fibril (CF) beads (MCCBs) loaded with laccase were prepared to degrade polychlorinated biphenyls (PCBs) in wastewater. The proper porous structure in MCCBs was achieved by introducing nano CaCO₃ (as a pore forming agent) in cellulose/CF (CCBs) beads during the preparation process. Cellulose/CF composite beads were modified by maleic anhydride to introduce carboxyl groups. Laccase was immobilized on the MCCBs through electrostatic adsorption and covalent bonding. The effects of pH, laccase concentration and contact time on immobilization yields and recovered activity were investigated. The best conditions were pH 4, concentration 16 g/L and contact time 3 h. The immobilized laccase under these conditions showed a good performance in thermal and operational stability. The laccase immobilized on MCCB beads can remove 85% of 20 mg/L 4-hydroxy-3,5-dichlorobiphenyl (HO-DiCB) in wastewater. The results demonstrated that MCCBs, as a new type of green-based support, are very promising in material immobilizing laccase. This technology may be of potential advantage for the removal of polychlorinated biphenyls in wastewater from an environmental point of view.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/polym10070798DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6403812PMC
July 2018

Controlled release of agrochemicals and heavy metal ion capture dual-functional redox-responsive hydrogel for soil remediation.

Chem Commun (Camb) 2018 Dec;54(97):13714-13717

Department of Environmental Engineering, North China Electric Power University, 689 Huadian Road, Baoding, Hebei 071003, China.

Novel redox-responsive hydrogels were prepared based on disulfide-crosslinked carboxymethyl cellulose for the controlled-release of agrochemicals. After release, the reduced hydrogels could capture heavy metal ions in soil via strong complexation between the ions and thiol groups generated by disconnected disulfide bonds, thus benefiting plant growth and soil remediation synchronously.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1039/c8cc07872fDOI Listing
December 2018

Study on cellulose microfilaments based composite spheres: Microwave-assisted synthesis, characterization, and application in pollutant removal.

J Environ Manage 2018 Dec 11;228:85-92. Epub 2018 Sep 11.

Key Laboratory of Energy Resource Utilization from Agriculture Residue, Chinese Academy of Agricultural Engineering, Beijing 100125, China.

A novel study of synthesizing the temperature-responsive polymer grafted cellulose filaments/Poly (N-isopropylacrylamide) (NIPAM) spheres (P-MCCBs) was carried out for the removal of dyes and heavy metal ions. The novelty of the presented work consists of the application of the nano-sized pore-forming agent (Calcium Carbonate) and the introduction of a temperature-responsive monomer (NIPAM) while preparing the adsorbents. In addition, the spherical adsorbents were synthesized through an in-situ free radical polymerization using a microwave-assisted heating approach. The morphology, chemical structure, pH, and thermal sensitivity of P-MCCBs were characterized properly. The adsorption and desorption behaviors of dyes and heavy metal ions on P-MCCBs were also investigated. The results showed that P-MCCBs exhibited a fast adsorption rate, the adsorption equilibrium reached within 80 min and 40 min for MB and Pb, respectively (25 °C). Moreover, around 5-8% and 20% of adsorbed MB and Pb were released at the temperature above 45 °C. The adsorption kinetics followed pseudo-second-order model, and the desorption process was fit well using Higuchi and Korsmeyer-Peppas models. These results indicated that P-MCCBs could be served as a novel material for controllable adsorption and desorption processes of various contaminants.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jenvman.2018.09.021DOI Listing
December 2018
-->