Preparation Of Two Novel Alkaline PH-Response Copolymers And Their Application In Recycling Aqueous Two-Phase Systems

In this paper,a novel recycling aqueous two-phase system(ATPS)was constructed by two alkaline pH-response copolymers(PADB6.29 and PMDM7.19).And the partition coefficient of lincomycin was investigated in this ATPS.The monomers of PAADB6.29 were acrylic acid(AA),2-(dimethylamino)-ethyl methacrylate(DMAEMA),butyl methacrylate(BMA).And PMDM7.19 was synthesized by methacrylic acid(MAA),DMAEMA,methyl methacrylate(MMA).The molecular weight distribution of PADB6.29 and PMDM7.19 were measured by GPC.For PADB6.29,its Mn was 1.499×105D;Mw was 2.942×105D;M,,was 3.136×105D and Mz was 6.429×105D.But for PMDM7.19,its Mn was 6.224×105D;Mw was 7.714×105D;Mv was 3.205×105D and Mz was 1.131×106D.The intrinsic viscosity of PADB6.29 and PMDM7.19 were 213.0mL/mg and 215.6mL/mg,respectively.The partical size distribution of copolymers were measured by dynamic laser scattering(DLS).About 98.8%of PADB6.29 and 96.7%PMDM7.19 could be recovered by adjusting pH to their isoelectric points(6.29 and 7.19)which were tested by Zetasizer Nano ZEN3600(Malvern),respectively.The structures of both copolymers were characterized by Nicolet Magna-IR550 infrared equipment(Nicolet Company,USA)and Bruker spectroscopy DRX500 1H NMR equipment(Bruker Company,Switzerland).And the results were similar to the original ratios of raw material.The phase diagram was prepared by using the cloud point method to test the binodal curve.The samples were taken out from the top and bottom phases after 24h when the two phases were formed,and then the concentration of PADB6.29 and PMDM7.19 in both phases was measured by high performance liquid chromatography(HPLC)at 215nm to construct the tie lines.Besides,according to the investigation,when concentrations of PADB6.29 and PMDM7.19 were both 6%(w/w)and pH was between 8.4 and 8.7(±0.1)the PADB6.29/PMDM7.19 ATPS could formed with a clear phase interface.In this study,the partition behaviors of lincomycin was investigated in PADB6.29/PMDM7.19 ATPS.According to the experiments,the K can achieve to 0.17 at 30? with 10mM KBr and 5.5 at 40? with 80mM Ti(SO4)2.Above all,this novel ATPS is low cost and no environmental problem and has potential industry application.