Surface Plasmon Resonance Based Sensor for Amaranth Detection With Molecularly Imprinted Nanoparticles

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%.

Patulin Imprinted Nanoparticles Decorated Surface Plasmon Resonance Chips for Patulin Detection

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).