Amaranth imprinted nanoparticless were prepared by two-phase mini emulsion polymerization of hydroxyethyl methacrylate and ethylene glycol dimethacrylate using acrylamide and methacrylic acid as functional monomers.Th...Amaranth imprinted nanoparticless were prepared by two-phase mini emulsion polymerization of hydroxyethyl methacrylate and ethylene glycol dimethacrylate using acrylamide and methacrylic acid as functional monomers.The amaranth non-imprinted nanoparticle was prepared with the same procedure without using amaranth.Amaranth imprinted and non-imprinted nanoparticles were attached on the chip surface modified with allyl mercaptan.The surfaces of the surface plasmon resonance(SPR)sensor were characterized by the ellipsometry,contact angle,and atomic force microscopy.Amaranth solutions with different concentrations(0.1 mg/mL-150mg/mL)were prepared with the pH 7.4 phosphate buffer.The limit of detection and limit of quantification were 0.0180mg/mL and 0.06mg/mL,respectively.When the selectivity of the amaranth imprinted SPR sensor was compared with the competing molecules tartrazine and allura red,it was observed that the target molecule amaranth was 5.64 times and 5.18 times more selective than allura red and tartrazine,respectively.The liquid chromatography-mass spectrometry technique(LC-MS)was used for validation studies.According to the results obtained from both SPR sensor and LC-MS analyses,the amaranth recovery(%)from fruit juices was observed between 96%and 99%.展开更多
In this study,the patulin imprinted and the non-imprinted nanoparticles are synthesized by the two-phase mini emulsion polymerization method and characterized by zeta-size analysis,Fourier transform infrared spectrosc...In this study,the patulin imprinted and the non-imprinted nanoparticles are synthesized by the two-phase mini emulsion polymerization method and characterized by zeta-size analysis,Fourier transform infrared spectroscopy,and scanning electron microscopy.Afterwards,the patulin imprinted and the non-imprinted nanoparticles are attached on the surface of surface plasmon resonance(SPR)chips.The patulin imprinted and the non-imprinted SPR nanosensors are characterized by using atomic force microscope,ellipsometer,and contact angle measurements.Kinetic studies for patulin detection are carried out in the concentration range of 0.5nmol-750nmol.The limit of detection and the limit of quantification values are obtained as 0.011 nmol and 0.036 nmol,respectively.In all kinetic analysis,the response time is 13 min for equilibration,adsorption,and desorption cycles.The selectivity studies of the patulin imprinted and the non-imprinted SPR nanosensors are determined in the presence of ochratoxin A and aflatoxin Bl.In order to demonstrate the applicability,validation studies of the patulin imprinted SPR nanosensor are performed by liquid chromatography-tandem mass spectrometry(LC-MS).展开更多
The aim of the present study is to develop a surface plasmon resonance sensor for the detection of vitamin B2,vitamin B9,and vitamin B12 in food samples by using the molecular imprinting technique.The vitamin B2,vitam...The aim of the present study is to develop a surface plasmon resonance sensor for the detection of vitamin B2,vitamin B9,and vitamin B12 in food samples by using the molecular imprinting technique.The vitamin B2,vitamin B9,and vitamin B12 imprinted and the non-imprinted surface plasmon resonance sensor chip surfaces were characterized by using contact angle measurements,atomic force microscopy,ellipsometry,and Fourier transform infrared-attenuated total reflectance.The real-time detection of vitamin B2,vitamin B9,and vitamin B12 was analyzed by using aqueous solutions in the concentration range of 0.01 ng/mL−10 ng/mL for vitamin B2,0.1 ng/mL−8.0 ng/mL for vitamin B9,and 0.01 ng/mL−1.5 ng/mL for vitamin B12.The limit of detection values was calculated as 1.6×10^(−4) ng/mL for vitamin B2,13.5×10^(−4) ng/mL for vitamin B9,and 2.5×10^(−4) ng/mL for vitamin B12,respectively.Selectivity experiments were performed by using vitamin B1 and vitamin B6.The reproducibility of surface plasmon resonance sensors was investigated both on the same day and on different days for four times.Validation studies of the prepared surface plasmon resonance(SPR)sensors were performed by liquid chromatography-tandem mass spectrometry(LC-MS/MS).展开更多
Monosize, 1.6 μm, magnetic beads of poly（glycidyl methacrylate） [M-poly（GMA）], were prepared by dispersion polymerization in the presence of Fe3O4 nano-powder. Monosize M-poly（GMA） beads were characterized by s...Monosize, 1.6 μm, magnetic beads of poly（glycidyl methacrylate） [M-poly（GMA）], were prepared by dispersion polymerization in the presence of Fe3O4 nano-powder. Monosize M-poly（GMA） beads were characterized by swelling tests, density measurements, electron spin resonance （ESR）, vibrating sample magnetometer （VSM） and scanning electron microscopy （SEM）. The characteristic functional groups of M-poly（GMA） beads were analyzed by Fourier transform infrared spectrometer （FTIR）. The M-poly（GMA） beads are highly uniform in size and have a spherical shape and non-porous structure. Polydispersity index （PDI） of M-poly（GMA） beads was calculated to be around 1.008. The hydrated density of the M-poly（GMA） beads measured at 25 ℃ was 1.14 g/cm^3. The content of oxirane groups on the surface of the M-poly（GMA） sample was found to be 3.46 mmol/g by using perchloric acid titration. The specific surface area of the M-poly（GMA） beads was determined to be 3.2 m^2/g. The equilibrium swelling ratio was 52%. The volume fraction of magnetite nanopowder in the M-poly（GMA） beads was found to be 4.5%. The g factor, that can be considered as a quantity characteristic of the molecules in which the unpaired electrons are located, was found to be 2.28 for M-poly（GMA）. The external magnetic field at resonance was calculated to be 2055 Gs which was found sufficient to excite all of the dipole moments present in 1.0 g of M-poly（GMA） sample.展开更多
文摘Amaranth imprinted nanoparticless were prepared by two-phase mini emulsion polymerization of hydroxyethyl methacrylate and ethylene glycol dimethacrylate using acrylamide and methacrylic acid as functional monomers.The amaranth non-imprinted nanoparticle was prepared with the same procedure without using amaranth.Amaranth imprinted and non-imprinted nanoparticles were attached on the chip surface modified with allyl mercaptan.The surfaces of the surface plasmon resonance(SPR)sensor were characterized by the ellipsometry,contact angle,and atomic force microscopy.Amaranth solutions with different concentrations(0.1 mg/mL-150mg/mL)were prepared with the pH 7.4 phosphate buffer.The limit of detection and limit of quantification were 0.0180mg/mL and 0.06mg/mL,respectively.When the selectivity of the amaranth imprinted SPR sensor was compared with the competing molecules tartrazine and allura red,it was observed that the target molecule amaranth was 5.64 times and 5.18 times more selective than allura red and tartrazine,respectively.The liquid chromatography-mass spectrometry technique(LC-MS)was used for validation studies.According to the results obtained from both SPR sensor and LC-MS analyses,the amaranth recovery(%)from fruit juices was observed between 96%and 99%.
基金This study was partly supported by Scientific Research Foundation of Hacettepe University Project(Grant No.FHD-2019-18247).
文摘In this study,the patulin imprinted and the non-imprinted nanoparticles are synthesized by the two-phase mini emulsion polymerization method and characterized by zeta-size analysis,Fourier transform infrared spectroscopy,and scanning electron microscopy.Afterwards,the patulin imprinted and the non-imprinted nanoparticles are attached on the surface of surface plasmon resonance(SPR)chips.The patulin imprinted and the non-imprinted SPR nanosensors are characterized by using atomic force microscope,ellipsometer,and contact angle measurements.Kinetic studies for patulin detection are carried out in the concentration range of 0.5nmol-750nmol.The limit of detection and the limit of quantification values are obtained as 0.011 nmol and 0.036 nmol,respectively.In all kinetic analysis,the response time is 13 min for equilibration,adsorption,and desorption cycles.The selectivity studies of the patulin imprinted and the non-imprinted SPR nanosensors are determined in the presence of ochratoxin A and aflatoxin Bl.In order to demonstrate the applicability,validation studies of the patulin imprinted SPR nanosensor are performed by liquid chromatography-tandem mass spectrometry(LC-MS).
基金supported by a grant from Hacettepe University Scientific Research Projects Coordination Unit(Grant No.FBA-2015-8761).
文摘The aim of the present study is to develop a surface plasmon resonance sensor for the detection of vitamin B2,vitamin B9,and vitamin B12 in food samples by using the molecular imprinting technique.The vitamin B2,vitamin B9,and vitamin B12 imprinted and the non-imprinted surface plasmon resonance sensor chip surfaces were characterized by using contact angle measurements,atomic force microscopy,ellipsometry,and Fourier transform infrared-attenuated total reflectance.The real-time detection of vitamin B2,vitamin B9,and vitamin B12 was analyzed by using aqueous solutions in the concentration range of 0.01 ng/mL−10 ng/mL for vitamin B2,0.1 ng/mL−8.0 ng/mL for vitamin B9,and 0.01 ng/mL−1.5 ng/mL for vitamin B12.The limit of detection values was calculated as 1.6×10^(−4) ng/mL for vitamin B2,13.5×10^(−4) ng/mL for vitamin B9,and 2.5×10^(−4) ng/mL for vitamin B12,respectively.Selectivity experiments were performed by using vitamin B1 and vitamin B6.The reproducibility of surface plasmon resonance sensors was investigated both on the same day and on different days for four times.Validation studies of the prepared surface plasmon resonance(SPR)sensors were performed by liquid chromatography-tandem mass spectrometry(LC-MS/MS).
文摘Monosize, 1.6 μm, magnetic beads of poly（glycidyl methacrylate） [M-poly（GMA）], were prepared by dispersion polymerization in the presence of Fe3O4 nano-powder. Monosize M-poly（GMA） beads were characterized by swelling tests, density measurements, electron spin resonance （ESR）, vibrating sample magnetometer （VSM） and scanning electron microscopy （SEM）. The characteristic functional groups of M-poly（GMA） beads were analyzed by Fourier transform infrared spectrometer （FTIR）. The M-poly（GMA） beads are highly uniform in size and have a spherical shape and non-porous structure. Polydispersity index （PDI） of M-poly（GMA） beads was calculated to be around 1.008. The hydrated density of the M-poly（GMA） beads measured at 25 ℃ was 1.14 g/cm^3. The content of oxirane groups on the surface of the M-poly（GMA） sample was found to be 3.46 mmol/g by using perchloric acid titration. The specific surface area of the M-poly（GMA） beads was determined to be 3.2 m^2/g. The equilibrium swelling ratio was 52%. The volume fraction of magnetite nanopowder in the M-poly（GMA） beads was found to be 4.5%. The g factor, that can be considered as a quantity characteristic of the molecules in which the unpaired electrons are located, was found to be 2.28 for M-poly（GMA）. The external magnetic field at resonance was calculated to be 2055 Gs which was found sufficient to excite all of the dipole moments present in 1.0 g of M-poly（GMA） sample.
