title: Directly suspended droplet microextraction in combination with microvolume UV-vis spectrophotometry for determination of phosphate.
abstract: A miniaturized methodology for the determination of phosphate in waters has been developed by combining directly suspended droplet microextraction (DSDME) with microvolume spectrophotometry. The method is based on the extraction of the ion pair formed between 12-molybdophosphate and malachite green onto a microdrop of methyl isobutyl ketone and subsequent spectrophotometric determination with no dilution. An enrichment factor of 325 was obtained after 7.5 min of microextraction. The detection limit was 6.1 nM phosphate and the repeatability, expressed as relative standard deviation, was 2.7% (n=6). The method was successfully applied to the determination of dissolved reactive phosphorus in different freshwater samples.
authors: Departamento de Química Analítica y Alimentaria, Área de Química Analítica, Facultad de Química, Universidad de Vigo, Campus As Lagoas-Marcosende s/n, 36310 Vigo, Spain.
authors: Francisco
authors: F
authors: Pena-Pereira
authors: Noelia
authors: N
authors: Cabaleiro
authors: Inmaculada
authors: I
authors: de la Calle
authors: Marta
authors: M
authors: Costas
authors: Sandra
authors: S
authors: Gil
authors: Isela
authors: I
authors: Lavilla
authors: Carlos
authors: C
authors: Bendicho
mesh_terms: D005591:Chemical Fractionation / Q000379:methods*; D008904:Miniaturization; D010710:Phosphates / Q000032:analysis* / Q000737:chemistry / Q000302:isolation & purification*; D015203:Reproducibility of Results; D012394:Rosaniline Dyes / Q000737:chemistry; D012965:Sodium Chloride / Q000737:chemistry; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry; D012997:Solvents / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet / Q000379:methods*; D013997:Time Factors; D014320:Triphenylmethyl Compounds / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D010710:Phosphates; D012394:Rosaniline Dyes; D012997:Solvents; D014320:Triphenylmethyl Compounds; D014867:Water; C005095:malachite green; D012967:Sodium Dodecyl Sulfate; D012965:Sodium Chloride; C046945:triphenylmethane