Controllable Synthysis Of Pt Nanoparticles Base On Platinum Inorganic Binding Peptide

Inorganic binding peptides, one kind of 7-20AA peptides that are found in virto of some kind of microorganism have the ability of binding to some inorganic compounds,include metal. It serve as template and in process of synthesis of organic invito.Pt binding peptides is a kind of 7 AA peptides that have particular binding ability to platinum.There are four sequeces have been digged out so far: QSVTSTK,DRTSTWR,TSPGQKQ,SSSHLNK,(naming as PT1,PT2,PT3 and PT4 coresspondingly).In this report the synthesized peptide PT2(DRTSTWR) has been employed as template for preparation of platinum nanoparticles. Platinum crystallites were obtained by the way that PtCl₄ reacted with PT2 immobilized on the surface of protonated PET-N(CH₃) ₂ film. The platinum nanoparticles that ranged from 1nm to 2nm in size were obtained with the free PT2 and PtCl₄ mixed together in solution at room temperature and pH 7 for 24h. Both the crystallites and nanoparticles of platinum were characterized by TEM, XPS and EDX. Based on the data above, that PT2 could be utilized as template for biomimetic synthesis of platinum nanoparticles in vitro was confirmed.Subsequently, in order to prepare shape and size controllable nanoparticles of platinum two stabilizing agents chitosan and sodium polyacrylate with different concentration were added into the reaction solution respectively resulting in the variation of the size and shape of the platinum particles. Specifically, platinum particles that ranged from 12nm to 15．5nm in size and are inclined to array in line were obtained when the molar proportion of chitosan to Pt⁴⁺ was 5/1 in the solution. In the presence of sodium polyacrylate whose amount is 5 times of Pt⁴⁺, more uniformly spherical platinum particles of 7-8nm in size were synthesized.Illumined by core-shell construction, a new and more efficiency route was designed.first,5-6nm nanopaticles were synthsysed following Terranish's route,methenal deoxidization method.All of PtC16²⁺ have been used up in the beginning 30 minutes tested by UV spectrum. 12nm Pt nanopatícles were prepared by adding 5-6nm Pt crystals into fresh prepared PT2 and PtCl6²⁺ solution mixture and warmed in 68℃for 2 hours. 16nm Pt nanopaticles were prepared by adding 12nm Pt crystals into fresh prepared PT2 and PtCl6²⁺ solution mixture and warmed in 68℃for 2 hours.