Absorption &transport& Accumulation Of Titanium Dioxide In Plants And Function Methods Between Protein And Metal

Nano-sized TiO₂ began to be manufactured in the late 80s'of the 20th century. NanosizedTiO2 widely used as catalyst,UV absorber,gas sensors and many other areas, because ofits unique optical and electrical properties. With the development of nanotechnology, peopleare actively exploring a new method in field of biology applications, in which nanometertitanium dioxide plays an important role. Research are mainly focused on the role ofnanometer titanium dioxide in controlling the growth of micro-organism and lower plants,while there are few studies for the growth of nanotechnology on the higher plants.In this paper, the effects of nano-sized Titanium dioxide on the growth of higher plants,as well as the absorption, transport and accumulation of Titanium element, which treated withdifference concentration and particle size were discussed. The phytotoxicity of nano-TiO2 onhigher plant species (cucumber) were investigated in the present study by means of rootelongation experiments. The results show that nano-TiO2 severely inhibited the rootelongation and the germination percentage of the cucumber. The contents of Ti element inroots, stem and leaves tissue were measured by ICP-MS. The results show that the contentsincreased, while decreased the diameter of particles which are similar to that by SRXRF. Thedistribution of metal element in cucumber roots are measured by Synchrotron radiation X-rayfluorescence, and the result showed that Titanium element accumulated in the roots. Inaddition, quantum dots as a probe in organism was used to trace element due to their physicaland chemical properties, and we got a significant phenomenon that quantum dots could interthe roots of cucumber and accumulate the surrounding region by the cells.To study the effect of titanium dioxide on plant growth mechanism and searching for thetarget molecules, Immobilized metal affinity chromatography (IMAC) was used to separatemetal-protein, which have binded sites for metal. Immobilized metal affinity chromatography(IMAC) is a new method and was developed in the last 20 years. In order to optimizing theconditions of extracting proteins, we choose liver tissue as the research object due to its enriching in proteins. The human liver tissue was separated by IMAC and the relationshipbetween nano-particles and protein was discussed. Immobilized Metal AffinityChromatography is an effective technology for separation of metal protein. The results showthat Cu-IMAC is the most effective method for the separation and purification of metalprotein,Ni-IMAC followed, and Zn-IMAC and Co-IMAC the last; When reduced the pH ofelution buffer, more proteins were collected. Besides, chelator competition elution buffer showbetter than effects of pH. Therefore, the best method of combination on protein separation ofhuman tissue was chosen: copper-IMAC with low pH elution buffers(pH 3.8-5.8)andchelator competition elution buffer with 500mM imidazole.