Separation of Phenylarsonic Compounds by Ion Pairing–Reversed Phase–High Performance Liquid Chromatography

Abstract

Sebatian fenilarsonik digunakan dengan meluas sebagai bahan tambah makanan ternakan bagi membantu proses tumbesaran dan mengawal penyakit di dalam industri ternakan ayam. Satu kaedah dijalankan bagi analisis arsenik di dalam bahan tambah makanan ternakan secara HPLC fasa terbalik–pasangan ion dengan pengesan ultralembayung. Dengan menggunakan turus oktadekilsililsilika, pemisahan sebatian arsenik anion [asid 3–nitro–4–hidroksifenilarsonik (3–NHPAA), asid p–arsanilik (p–ASA) dan asid fenilarsonik (PA)] telah diperoleh menggunakan tetrabutilammonium klorida 5 mM sebagai reagen pasangan ion di dalam fasa bergerak yang mengandungi asid malonik 3 mM dan 5% metanol pada kadar alir 1.4 mL min–1. Pengaruh pH fasa bergerak ke atas pemisahan dikaji dan didapati pH optimum adalah 5.85. Had pengesanan yang diperoleh bagi 3–NHPAA ialah 0.43 ng As. Kata kunci: arsenik; bahan tambah makanan ternakan; HPLC fasa terbalik-pasangan ion Phenylarsonic compounds are extensively used as feed additives to promote growth and to control disease in the poultry industry. A method was conducted that allowed the analysis of arsenic animal feed additives by ion pairing–reversed phase HPLC (IP–RP–HPLC) with a UV detection using an octadecylsilylsilica column. The separation of anionic arsenic compounds [3–nitro–4–hydroxyphenylarsonic acid (3–NHPAA), p–arsanilic acid (p ASA) and phenylarsonic acid (PA)] was accomplished using 5 mM tetrabutylammonium chloride as the ion pairing reagent in aqueous mobile phase containing 3 mM malonic acid and 5% methanol at a flow rate of 1.4 mL min–1. The influence of mobile phase pH on the separation was studied; the optimum pH found was 5.85. The detection limit obtained for 3–NHPAA was 0.43 ng As. Key words: arsenic; animal feed additives; ion pairing-reversed phase-high performance liquid chromatography