Modifications of spectrophotometric methods for total phosphorus determination in meat samples

Spectrophotometric determination of total phosphorus in meat samples was modified using the molybdenum blue reaction with the following reducing agents: ascorbic acid ( AA), hydrazine sulphate (HS), and mixture of hydroquinone and hydrazine sulphate (HHS). Proposed methods were validated by evaluation of statistical parameters such as: linearity, sensitivity, limits of detection (DL) and quantification (QL), precision, and accuracy, against the standard and malachite green (MG) modified procedures and by applying food certified materials. The values of within-day and between-days precision in meat samples for all tested reducing agents were better than 3.4 % and 4.2 %, respectively. The recoveries for CRMs analyses were between 92 % and 102.3 %. Obtained results suggest usefulness of the hydroquinone and hydrazine sulphate mixture in the determination of phosphorus ions. (C) 2008 Institute of Chemistry, Slovak Academy of Sciences