Rosmarinic acid determination using biomimetic sensor based on purple acid phosphatase mimetic.
A new heterodinuclear Fe(III)Zn(II) complex which mimics the active site of the hydrolytic enzyme red kidney bean purple acid phosphatase was synthesized and characterized by IR, CHN and X-ray crystallographic analyses. This complex, [Fe(III)Zn(II)(mu-OH)bpbpmp-CH(3)](ClO(4))(2), containing the ligand (H(2)bpbpmp-CH(3) = {2-[bis(2-pyridylmethyl)aminomethyl]-6-[(2-hydroxy-5-methylbenzyl) (2-pyridyl-methyl) aminomethyl]-4-methyl-phenol}) was employed in the construction of a biomimetic sensor and used in the determination of rosmarinic acid in plant extract samples. The response parameters and optimization of the biomimetic sensor design were evaluated. The best performance of this sensor was obtained for 75:15:10% (w/w/w) of the graphite powder:nujol:Fe(III)Zn(II) complex, 0.1 mol L(-1) phosphate buffer solution (pH 7.5), 1.19x10(-4) mol L(-1) hydrogen peroxide with frequency, pulse amplitude, and scan increment at 30 Hz, 100 mV, and 0.6 mV, respectively. The rosmarinic acid concentration was linear in the range of 2.98x10(-5) to 3.83x10(-4) mol L(-1) (r=0.9991) with a detection limit of 2.30x10(-6) mol L(-1). This biomimetic sensor demonstrated long-term stability (300 days; 900 determinations) and reproducibility, with a relative standard deviation of 12.0%. The recovery study of rosmarinic acid in plant extract samples gave values from 90.3 to 98.3% and the concentrations determined showed agreement when compared with those obtained using capillary electrophoresis at the 95% confidence level.
Santhiago
Murilo
M
Departamento de Química, Universidade Federal de Santa Catarina, CEP 88040-900, Florianópolis, SC, Brazil.
Peralta
Rosely A
RA
Neves
Ademir
A
Micke
Gustavo Amadeu
GA
Vieira
Iolanda Cruz
IC
D000135:Acid Phosphatase / Q000737:chemistry* / Q000378:metabolism*; D040761:Biomimetic Materials / Q000138:chemical synthesis / Q000737:chemistry*; D032701:Biomimetics / Q000379:methods*; D002623:Chemistry Techniques, Analytical / Q000379:methods*; D002934:Cinnamates / Q000032:analysis*; D018360:Crystallography, X-Ray; D053630:Depsides / Q000032:analysis*; D004563:Electrochemistry; D019075:Electrophoresis, Capillary; D005290:Ferric Compounds / Q000737:chemistry; D006023:Glycoproteins / Q000737:chemistry* / Q000378:metabolism*; D006801:Humans; D010936:Plant Extracts / Q000737:chemistry; D015203:Reproducibility of Results; D013055:Spectrophotometry, Infrared; D017967:Zinc Compounds / Q000737:chemistry; D000097123:Rosmarinic Acid
D000135:Acid Phosphatase; D002934:Cinnamates; D053630:Depsides; D005290:Ferric Compounds; D006023:Glycoproteins; D010936:Plant Extracts; D017967:Zinc Compounds; D000097123:Rosmarinic Acid; C091137:purple acid phosphatase