Residue depletion of ractopamine and its metabolites in swine tissues, urine, and serum

Zhiyi Qiang, Fenqin Shentu, Bing Wang, Jianping Wang, Jianyu Chang, Jianzhong Shen

Research output: Contribution to journalArticlepeer-review

48 Scopus citations


Ractopamine hydrochloride is a β-adrenergic leanness-enhancing agent approved for use in swine in the United States. Depletion of ractopamine and its metabolites from animal tissues, urine, and serum is of interest for the detection of illegal use. The objectives of this study were to measure the residues of ractopamine in swine incurred samples after treatment with dietary ractopamine for 28 consecutive days. An efficient and sensitive analytical method was developed for the detection of parent ractopamine and its metabolites in swine tissues, urine, and serum by HPLC-FLD. After extraction, enzymatic digestion, and solid-phase cleanup of the samples, ractopamine residues were determined by liquid chromatography (LC) with fluorescence detector. The limits of detection (LOD) for tissues, urine, and serum were 1 ng g-1, 0.5 ng mL-1, and 0.5 ng mL-1, respectively. Recoveries ranged from 70.5 to 94.5% for samples fortified at 1-50 ng g-1 or ng mL -1. Sixty pigs were fed twice daily for 28 consecutive days with feeds containing 18 mg kg-1 ractopamine HCl. The residue concentrations in urine, liver, and kidney were 650.06 ng mL-1, 46.09 ng g-1, and 169.27 ng g-1, respectively, compared with those in muscle, fat, and serum (4.94 ng g-1, 3.28 ng g-1, and 7.48 ng mL-1, respectively) at the feeding period of 7 days. The residue concentrations at withdrawal period of 0 days in all edible tissues were lower than tolerance values established by the FDA and MRL values listed by the JECFA. These data support the withdrawal time of 0 days established by the FDA for ractopamine used as feed additive in swine.

Original languageEnglish (US)
Pages (from-to)4319-4326
Number of pages8
JournalJournal of Agricultural and Food Chemistry
Issue number11
StatePublished - May 30 2007
Externally publishedYes


  • Ractopamine
  • Residue depletion
  • Swine

ASJC Scopus subject areas

  • General Chemistry
  • General Agricultural and Biological Sciences


Dive into the research topics of 'Residue depletion of ractopamine and its metabolites in swine tissues, urine, and serum'. Together they form a unique fingerprint.

Cite this