A Novel Colorimetric Sensing Material, Poly(gamma-Glutamic acid)-graft-3,4-Dihydro-3-(2 '-ethyl hydroxyl)-6-Ethyl-1,3,2H-Benzoxazine (gamma-PGA-graft-ethyl-Bx), for Iron(III) Ions

作者：Choothong Nu Orn; Kaewvilai Attaphon; Laobuthee Apirat^*; Lertworasirikul Amornrat

来源：Sains Malaysiana, 2013, 42(2): 223-229.

• Benzoxazine
• colorimetric sensing materials
• photometric titration method
• transition metal ion
• gamma-PGA

A novel rapid ion colorimetric sensing material for iron(III) ions was developed from poly(gamma-glutamic acid) and 3,4-dihydro-3-(2'-ethyl hydroxyl)-6-ethyl-1,3,2H-benzoxazine (ethyl-Bx). The benzoxazine as an ionophore segment was grafted into gamma-PGA backbone via the esterification reaction, which is a simple and effective reaction. The structure of gamma-PGA-graft-ethyl-Bx was characterized by using FT-IR and H-1-NMR. The most attainable degree of conversion was 25%. The gamma-PGA-graft-ethyl-Bx showed a highly selective and sensitive recognition toward iron(III), which was clearly observable with the naked eye. The iron(III) ions sensing property of gamma-PGA-graft-ethyl-Bx was further examined by using photometric titration method. After the interaction between the gamma-PGA-graft-ethyl-Bx and iron(III) ions was formed, the solution of the polymer in dimethyl sulfoxide was changed from clear and colorless to red color, resulting in the shift of the maximum wavelength from UV to visible range.

• 出版日期2013-2