Co-reporter:Lingmin Wu, Fei Liu, Gailing Wang, Zhian Guo and Jingchan Zhao
RSC Advances 2016 vol. 6(Issue 1) pp:464-471
Publication Date(Web):08 Dec 2015
DOI:10.1039/C5RA19565A
A novel composite material consisting of multi-walled carbon nanotube (MWNTs)-molecularly imprinted polymers (MIPs) for a tartrazine assay was synthesized by a surface molecular imprinting technique. The molecularly imprinted polymers were prepared with beta-cyclodextrins and [2-(methacryloyloxy) ethyl]trimethylammonium chloride (DMC) as bifunctional monomers. The MWNTs-MIPs were characterized using transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FT-IR). Adsorption experiments showed that the MWNTs-MIPs exhibited a high capacity and favourable selectivity toward tartrazine, and the maximum adsorption capacity, qm, and distribution coefficient, kd, were estimated to be 135.15 mg g−1 and 14.72, respectively. A SPE-HPLC analytical method was developed and used to assay tartrazine in five drinks. The recoveries were in the range from 88.6–102.4% with a relative standard deviation below 5.0%. The tartrazine content was lower in all samples than the permitted maximum limit set by the European Commission and Ministry of Health of the People’s Republic of China. A t test demonstrated that this method had no significant difference to the Chinese standard method of GB/T 5009.35-2003 at P = 0.95.
Co-reporter:Jingchan Zhao;Gailing Wang;Ting Cao;Zhian Guo
Food Analytical Methods 2016 Volume 9( Issue 1) pp:156-163
Publication Date(Web):2016 January
DOI:10.1007/s12161-015-0183-x
In this paper, a novel derivative reagent, ethoxyamine hydrochloride (EAHC), was proposed for formaldehyde detection with a simple and highly sensitive pre-column derivation–high-performance liquid chromatography. The effects such as the concentration of derivative reagent, buffer solution pH, reaction temperature, and reaction time on the derivate reaction were also investigated. Under the optimized experimental conditions, the peak area showed a linear relationship with the concentration of formaldehyde in a range of 0.046 to 4.6 mg L−1, with a correlation coefficient of 0.9998. The limit of detection (LOD) and the limit of quantification (LOQ) were 0.016 and 0.042 mg L−1, respectively. The proposed method was applied to the assay of different beer samples, and the recovery of the developed method was in the range of 91.3–104.3 %. To further evaluate the validity of the developed method, formaldehyde was also determined in different beer samples by the referenced HPLC method based on pre-column derivatization with 2, 4-dinitrophenylhydrazine (DNPH). Through the t test method, no obvious difference between the two methods was found at a 95 % confidence level. The results showed that the proposed method was a rapid, convenient, and feasible method for the determination of formaldehyde in beer samples.
Co-reporter:Fei Liu, Shengchen Zhang, Gailing Wang, Jingchan Zhao and Zhian Guo
RSC Advances 2015 vol. 5(Issue 29) pp:22811-22817
Publication Date(Web):20 Feb 2015
DOI:10.1039/C4RA14719G
A novel bifunctional molecularly imprinted polymer was synthesized in an aqueous system with Congo red as template, beta-cyclodextrin-maleic anhydride (β-CD-MA) and [2-(methacryloyloxy) ethyl] trimethylammonium chloride (DMC) as co-functional monomers and N,N-methylenebisacryl amide (MBA) as cross-linking agent, respectively. MIP was used as selective sorbent for the solid-phase extraction (SPE) of Congo red from food. And the elution was determined by HPLC. The mean recovery was 84.2–105.2%, the RSD ≤ 1.2%, the repeatability was 1.1–3.8%. The LOD and LOQ were 0.07 and 0.23 μg kg−1, respectively. The evaluation of validation data verified that the MIP has high selectivity and recovery, and it can be applied for the selective extraction and determination of Congo red in food.
Co-reporter:Jingchan Zhao, Fei Liu, Gailing Wang, Ting Cao, Zhian Guo and Yanfeng Zhang
Analytical Methods 2015 vol. 7(Issue 1) pp:309-312
Publication Date(Web):04 Nov 2014
DOI:10.1039/C4AY02212B
A rapid, simple and sensitive method for the determination of formaldehyde in exhaust gas was developed. Formaldehyde determination is based on the derivative reaction between formaldehyde and unsymmetrical dimethylhydrazine as a new derivatization agent. The derivative, unsymmetrical dimethylhydrazone, was detected by high performance liquid chromatography equipped with a diode array detector. Under the optimum experimental conditions, the response of the detection system was linear in the range of 0.0392–7.84 mg L−1, with a correlation coefficient of 0.9999. The detection limit (3S/N) of the method was 0.005 mg L−1, the mean recovery was 88.9–102.5%, and the repeatability was 2.6–5.4%. The evaluation of validation data verified that the proposed method was feasible for the determination of formaldehyde in engine exhaust.
Co-reporter:Weili Tang;Bijing Sha ;Hong Liu
Journal of Applied Polymer Science 2013 Volume 127( Issue 4) pp:2803-2808
Publication Date(Web):
DOI:10.1002/app.37607
Abstract
In this study, β-cyclodextrin (β-CD) was covalently grafted on hydroxyapatite (HA) using a coupling agent to improve the drug loading capacity and prolong the drug release. The binding of β-CD on the HA surface was confirmed by Fourier transformation infrared spectroscopy, thermal gravimetric analysis, and X-ray powder diffraction. The adsorption capacity of ofloxacin on β-CD-grafted hydroxyapatite (β-CD-g-HA) composite was found to be 30 mg g−1 at 37°C and 24 h. The adsorption process is spontaneous, given the negative values of free energy change. Compared with the release of ofloxacin loaded on HA, the release of ofloxacin loaded on β-CD-g-HA was slowed down 28% and 21% in pH 2.0 and pH 7.4 buffer media at 2 h, respectively. Biocompatibility of β-CD-g-HA was assessed by MTT assay, and the result showed that it had no cytotoxicity. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Co-reporter:Tao-jing Chen, Jing-chan Zhao, Zhi-an Guo and Bai-xin Zhang
Analytical Methods 2012 vol. 4(Issue 12) pp:4237-4243
Publication Date(Web):06 Nov 2012
DOI:10.1039/C2AY26084K
A molecularly imprinted polymer (MIP) for separation and enrichment of doxycycline (DC) has been synthesized using DC as the template, acrylamide-tung oil acid methyl ester (AM-ESA) and propenoic acid (AA) as the functional monomers, ethylene glycol dimethacrylate (EGDMA) as the cross-linker and 2,2′-azo-bis-isobutyronitrile (AIBN) as the initiator. The chemical and morphological characteristics of the MIPs were investigated by FT-IR and SEM. The static and kinetic adsorption, selectivity and recovery of the polymers were evaluated. The results indicated that the MIPs had higher chemical affinity for DC than the non-imprinted polymer (NIP). The maximum adsorption capacity of the DC-MIPs was calculated to be 257 μmol g−1. Finally, the MIPs were successfully used as a stationary phase for solid-phase extraction (SPE) to enrich DC from beef samples and the recoveries were in the range of 92.5–96.4% with RSDs of 3.1–7.0%.
Co-reporter:Jing-Chan Zhao;Yong-Ke Zhang;Yan-Feng Zhang;Zhi-An Guo;Bing Han;Guo-Ning Fan
Journal of Applied Polymer Science 2008 Volume 109( Issue 6) pp:4049-4053
Publication Date(Web):
DOI:10.1002/app.28608
Abstract
Inverse gas chromatography (IGC) studies on the surface of polyethylene (PE) particles grafted with acrylic acid and acryl amide have been reported. Surface properties of the virgin and grafting-modified PE were compared by IGC. The dispersive contributions of the surface free energy γ and the KA and KB parameters expressing the ability of the stationary phase to act as Lewis acid or Lewis base were calculated. The results showed that the γ value increased significantly after grafting. The PE samples grafted with acrylic acid and acrylamide showed a predominantly basic character while the virgin PE was acidic. All of these suggested that the surface of PE has been modified through the grafting reaction, and thus is expected to improve its adhesions with other polymers. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Co-reporter:Jingchan Zhao, Bing Han, Yanfeng Zhang, Dandan Wang
Analytica Chimica Acta 2007 Volume 603(Issue 1) pp:87-92
Publication Date(Web):5 November 2007
DOI:10.1016/j.aca.2007.09.024
Zn(II) ion-imprinted polymer materials used for solid-phase extraction (SPE) column were prepared by the copolymerization of 8-acryloyloxyquinoline (8-AOQ) monomer and a crosslinker ethylene glycol dimethacrylate (EGDMA) in the presence of 2,2′-azobisisobutyronitrile (AIBN) as an initiator. After removing Zn(II) ion from the polymer, molecularly imprinted polymers (MIPs) capable of selectively rebinding Zn(II) ion were obtained. The maximum adsorption capacity of Zn(II) on MIPs beads was about 3.9 mg g−1. The effect of pH and flow rate for quantitative enrichment was also investigated. The Zn(II)-imprinted microbeads have a greater affinity for Zn(II) with respect to Cu(II), Co(II) and Ni(II) ions. A detection limit of 0.65 μg L−1(3σ) and a relative standard deviation (R.S.D., n = 7) of 2.9% were obtained. The MIPs–SPE preconcentration procedure showed a linear calibration curve within concentration range from 0.65 to 130 μg L−1. Zn(II) ion-imprinted beads enabled the selective extraction of zinc ions from a complex matrix, and after 20 times of adsorption and desorption cycle, the recovery of adsorption capacity of Zn(II) on MIPs beads was only decreased 3.2%. The results suggested that these MIPs can be used several times without considerable loss of adsorption capacity.
Co-reporter:Guoning Fan;Hongan Yuan;Junlong Wang;Zhian Guo;Guozheng Liang
Journal of Applied Polymer Science 2006 Volume 102(Issue 1) pp:674-678
Publication Date(Web):28 JUL 2006
DOI:10.1002/app.24316
Graft copolymerization of acrylamide onto ultrahigh molecular weight polyethylene (UHMWPE) using horseradish peroxidase as catalyst was performed in different reaction solution to study the solvent effect. The factors affecting the grafting effect such as the solvents composition, initiator, reaction temperature, and reaction time were investigated. The grafted UHMWPE fiber surface was characterized by IR spectrum, scanning electron microscopy, thermal analysis, contact angle measurement, and single fiber pull out test. Polar groups such as CO and NH2 are approved to appear on the surface after treatment. The contact angle with water decreased from 85 to 50, indicating the wettability of the fiber has been increased. The surface of the grafted fiber became rougher and its adhesion to resin increased significantly, and hence is expected to produce reinforced plastics with resin. It was also found that the grafting effect was higher in dioxane than in other solvents used and the initiator substituted by electron donating group facilitates the grafting reaction. And the optimum reaction condition was determined to be reacting in 40% (v/v) dioxane solution at 30°C for 2 h. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 674–678, 2006
Co-reporter:Ting Cao, Weili Tang, Jingchan Zhao, Lulu Qin, Chunbo Lan
Journal of Bionic Engineering (January 2014) Volume 11(Issue 1) pp:125-133
Publication Date(Web):1 January 2014
DOI:10.1016/S1672-6529(14)60027-5
The purpose of this study is to explore and develop a novel biocompatibility drug delivery carrier for controllingontrolled drug release. The α-eleostearic acid grafted hydroxyapatite (α-ESA-g-HA) composite was synthesized by using silane coupling agent and characterized by Fourier Transformation Infrared Spectroscopy (FT-IR), Thermal Gravimetric Analysis (TGA) and Scanning Electron Microscope (SEM), respectively. The in vitro drug loading and controlled release behaviors of α-ESA-g-HA composite were investigated using ciprofloxacin as the model drug. The amount of ciprofloxacin loading and released was calculated by absorbance value which was determined by UV-Vis spectrophotometry at wavelength of 277 nm. The biocompatibility of α-ESA-g-HA composite was assessed by 3-(4,5)-dimethylthiahiazo(-z-yl)-3,5-di-phenytetrazoliumromide(MTT) assay, nuclear morphology and platelet adhesion. The results showed that the α-ESA-g-HA had nontoxic and good biocompatibility. According to the results mentioned above, the α-ESA-g-HA is an effective drug delivery carrier, which could increase drug loading capacity and control drug release, so further studies are necessary to evaluate clinical application and human health care.
Co-reporter:Tao-jing Chen, Jing-chan Zhao, Zhi-an Guo and Bai-xin Zhang
Analytical Methods (2009-Present) 2012 - vol. 4(Issue 12) pp:NaN4243-4243
Publication Date(Web):2012/11/06
DOI:10.1039/C2AY26084K
A molecularly imprinted polymer (MIP) for separation and enrichment of doxycycline (DC) has been synthesized using DC as the template, acrylamide-tung oil acid methyl ester (AM-ESA) and propenoic acid (AA) as the functional monomers, ethylene glycol dimethacrylate (EGDMA) as the cross-linker and 2,2′-azo-bis-isobutyronitrile (AIBN) as the initiator. The chemical and morphological characteristics of the MIPs were investigated by FT-IR and SEM. The static and kinetic adsorption, selectivity and recovery of the polymers were evaluated. The results indicated that the MIPs had higher chemical affinity for DC than the non-imprinted polymer (NIP). The maximum adsorption capacity of the DC-MIPs was calculated to be 257 μmol g−1. Finally, the MIPs were successfully used as a stationary phase for solid-phase extraction (SPE) to enrich DC from beef samples and the recoveries were in the range of 92.5–96.4% with RSDs of 3.1–7.0%.
