Study On Extraction Of Wheat Gliadin And The Preparation And Characterization Of Wheat Gliadin Embedded Magnetic Nano-particles

As the maximum content of storage proteins in wheat, wheat gliadin has a broad prospect inapplication of carrier material. At present,70%ethanol is usually used for extraction of wheatgliadin. However, study proves that organic solvent can induced protein denaturation, whichcould influence the application of wheat gliadin for carrier materials. So under the extractprocess of extraction, this study selected three organic solvents and considered extractionratio and protein denaturation, by this way to found the optimum conditions which had themaximum extraction ratio and the smallest protein denaturation. Then this study used wheatgliadin to produce microspheres. Also this study produced and used magnetic nano-particlesto enhance the targeting effect of the wheat gliadin microspheres. The main conclusions areas follows:This study used ethanol isopropanol and tertiary butyl alcohol to extract gliadin respectively,extraction ratio as index with which to determine optimum technological conditions. Theoptimum technological conditions as follows: The optimum technological conditions forextraction of wheat gliadin by ethanol were as follows: ethanol concentration65%, stirringfor4h, dilution ratio10∶1, under these conditions the extraction ratio is about35.6%; Theoptimum technological conditions for extraction of wheat gliadin by isopropanol were asfollows: isopropanol concentration65%, stirring for4h, dilution ratio10∶1, under theseconditions the extraction ratio is about35.3%; The optimum technological conditions forextraction of wheat gliadin by tertiary butyl alcohol were as follows: tertiary butyl alcoholconcentration65%, stirring for4h, dilution ratio10∶1, under these conditions the extractionratio is about31.6%. Therefore, the highest extraction rate was got by ethanol concentration65%.The analysis results of electrophoretic and infrared spectroscopy indicate that the lowestpurity wheat gliadin was obtained by tertiary butyl alcohol extraction, the highest puritywheat gliadin was obtained by65%ethanol extraction. The highest relative solubility ofwheat gliadin was0.805mg/mL by55%isopropanol extraction; the relative solubility effectof wheat gliadin0.653mg/mL was next by65%ethanol extraction. The wheat gliadinextracted by ethanol isopropanol and tertiary butyl alcohol had a similar denaturationtemperature which detected by DSC. Therefore, based on comprehensive consideration of purity, degeneration extent and cost of wheat gliadin in this paper, we selected65%ethanolas the best extraction solvent.The preparation processing conditions of wheat gliadin microspheres were studied by thesingle factor experiment. The optimum conditions for preparation of wheat gliadinmicrospheres were determined as follows: protein content10mg/ml, water addition60mL,glutaraldehyde addition150μL. Under these conditions, the wheat gliadin microspheres ofscanning electron microscopy （SEM） indicate that the samples with approximativelyspherical shape are with a narrow particle size ranged from1μm to5μm. When the wheatgliadin microspheres have stored in dryer for6months in normal temperature, the surface ofmicrospheres was basically no slump, this showed that the wheat gliadin microspheres have agood storage property.To enhance the targeting property and further reduce the size of the wheat gliadinmicrospheres, the study introduced magnetic nano-particles. The analysis results of infraredspectroscopy indicate that the sodium citrate and silica had cross-linked to the Fe₃O₄magnetic nano-particles surface successfully, the wheat gliadin also had embedded Fe₃O₄magnetic nano-particles successfully. This study had prepared three wheat gliadin embeddedmagnetic nano-particles. The FP is the wheat gliadin embedded magnetic nano-particleswhich had not been modified by anything with the size of50¹60nm have the worstagglomeration, but have best hydrophilicity and better magnetic properties. The FCP is thewheat gliadin embedded magnetic nano-particles which had been modified by sodium citratewith the size of50⁸0nm have some agglomeration, better hydrophilicity but worst magneticproperties. The FCTP is the wheat gliadin embedded magnetic nano-particles which had beenmodified by sodium citrate and silica with the size of50⁹0nm have no agglomeration, worsthydrophilicity but best magnetic properties. Therefore, based on comprehensive considerationof the particle size hydrophilicity agglomeration and magnetic properties, the FCTP are thebest product.