A nanocomposite prepared from a polypyrrole deep eutectic solvent and coated onto the inner surface of a steel capillary for electrochemically controlled microextraction of acidic drugs such as losartan
The authors describe a new coating for use in electrochemically controlled in-tube solid phase microextraction (EC-IT-SPME). It consists of a nanocomposite that was prepared from polypyrrole and deep eutectic solvent (DES) by electrochemical deposition on the inner walls of a stainless steel capillary that serves as a working electrode. The hypertension drug losartan acts as an acidic model analyte. The extraction efficiency, mechanical stability, chemical stability and lifetime of the coating were investigated. It is found to be quite stable in relatively acidic and basic media and to be re-usable >450 times without decrease in extraction efficiency. Its extraction capability in comparison to the commercial polypyrrole coating is better by a factor of 1.5. The coated steel capillary was used as the anode (anion-exchanger), and a platinum electrode was used as the cathode. By passing a sample solution through the electrode, losartan can be extracted by applying a positive potential to the flow. In the next step, losartan is electrochemically desorbed and subjected to HPLC analysis with UV detection. Under optimal conditions, losartan can be quantified with limits of detection that range from 50 to 500 ng L−1 depending on the sample matrix. Response is linear in the 0.1–500 μg L−1 concentration range. The inter- and intra-assay precisions (RSDs; in %, for n = 3) are in the range from 2.4–4.6% and from 1.9–3.9%, respectively.
KeywordsAnionic drugs Electrochemically controlled in-tube solid phase microextraction Electrochemical deposition High performance liquid chromatography Steel capillary Plasma Urine
Financial support from Tarbiat Modares University is gratefully acknowledged.
Compliance with ethical standards
The author(s) declare that they have no conflict of interests.
- 3.Wu J, Tragas C, Lord H, Pawliszy J (2002) Analysis of polar pesticides in water and wine samples by automated in-tube solid-phase microextraction coupled with high-performance liquid chromatography–mass spectrometry. J Chromatogr A 976:357–367. https://doi.org/10.1016/S0021-9673(02)01072-5 CrossRefGoogle Scholar
- 6.Asiabi H, Yamini Y, Seidi S, Esrafili A, Rezaei F (2015) Electroplating of nanostructured polyaniline–polypyrrole composite coating in a stainless-steel tube for on-line in-tube solid phase microextraction. J Chromatogr A 1397:19–26. https://doi.org/10.1016/j.chroma.2015.04.015 CrossRefGoogle Scholar
- 9.Asiabi H, Yamini Y, Seidi S, Shamsayei M, Safari M, Rezaei F (2016) On-line electrochemically controlled in-tube solid phase microextraction of inorganic selenium followed by hydride generation atomic absorption spectrometry. Anal Chim Acta 922:37–47. https://doi.org/10.1016/j.aca.2016.04.001 CrossRefGoogle Scholar
- 13.Saraji M, Rezaei B, Boroujeni MK, Bidgoli AAH (2013) Polypyrrole/sol–gel composite as a solid-phase microextraction fiber coating for the determination of organophosphorus pesticides in water and vegetable samples. J Chromatogr A 1279:20–26. https://doi.org/10.1016/j.chroma.2013.01.017 CrossRefGoogle Scholar
- 14.Sarafraz-Yazdi A, Rounaghi G, Razavipanah I, Vatani H, Amiri A (2014) New polypyrrole carbon nanotubes–silicon dioxide solid-phase microextraction fiber for the preconcentration and determination of benzene, toluene, ethylbenzene, and o-xylene using gas liquid chromatography. J Sep Sci 37:2605–2612. https://doi.org/10.1002/jssc.201400178 CrossRefGoogle Scholar
- 20.Wu M, Zhang H, Zhao F, Zeng B (2014) A novel poly(3,4-ethylenedioxythiophene)-ionic liquid composite coating for the headspace solid-phase microextraction and gas chromatography determination of several alcohols in soft drinks. Anal Chim Acta 850:41–48. https://doi.org/10.1016/j.aca.2014.08.029 CrossRefGoogle Scholar
- 29.Zhang M, Wei F, Zhang Y, Nie J, Feng Y (2006) Novel polymer monolith microextraction using a poly(methacrylic acid-ethylene glycol dimethacrylate) monolith and its application to simultaneous analysis of several angiotensin II receptor antagonists in human urine by capillary zone electrophoresis. J Chromatogr A 1102:294–301. https://doi.org/10.1016/j.chroma.2005.10.057 CrossRefGoogle Scholar
- 30.Nie J, Zhang M, Fan Y, Wen Y, Xiang B, Feng Y (2005) Biocompatible in-tube solid-phase microextraction coupled to HPLC for the determination of angiotensin II receptor antagonists in human plasma and urine. J Chromatogr B 828:62–69. https://doi.org/10.1016/j.jchromb.2005.09.015 CrossRefGoogle Scholar