Spectrofluorometric determination of L-tryptophan after preconcentration using multi-walled carbon nanotubes

Vol 2, Issue 01, Pages 43-48 **** Filed: Bioanalysis

  • Ehsan Zolfonoun
Keywords: L-tryptophan, Solid-phase extraction, Multi-walled carbon nanotubes, Bioanalysis, Spectrofluorometry


A solid-phase extraction method based on multi-walled carbon nanotubes (MWCNTs) was applied for the preconcentration of L-tryptophan prior to its spectrofluorometric determination. Due to the high surface area of MWCNTs, satisfactory concentration factor and extraction recovery can be achieved with only 10 mg MWCNTs in 5 min. The effects of pH, sorbent amount, eluent type and time on the recovery of the analyte were investigated. Under the optimum conditions, the detection limit for L-tryptophan was 8.9 ng mL−1. The precision of the method, evaluated as the relative standard deviation obtained by analyzing of 10 replicates, was 2.6%. The practical applicability of the developed method was examined using wheat and barley samples.

Author Biography

Ehsan Zolfonoun

Material and Nuclear Fuel Research school, Nuclear Science and Technology Research Institute, Tehran, Iran


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How to Cite
Zolfonoun, E. (2019). Spectrofluorometric determination of L-tryptophan after preconcentration using multi-walled carbon nanotubes. Analytical Methods in Environmental Chemistry Journal, 2(01), 43-48. https://doi.org/10.24200/amecj.v2.i01.43
Original Article