Simultaneous determination of angiotensins II and 1-7 by capillary zone electrophoresis in plasma and urine from hypertensive rats

• Published in: Talanta (Oxford) Vol. 80; no. 5; pp. 1702 - 1712
• Main Authors: Tenorio-López, Fermín Alejandro, Zarco-Olvera, Gabriela, Sánchez-Mendoza, Alicia, Rosas-Peralta, Martín, Pastelín-Hernández, Gustavo, del Valle-Mondragón, Leonardo
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.03.2010; Elsevier
• Subjects: Analytical chemistry; Angiotensin I - blood; Angiotensin I - urine; Angiotensin II; Angiotensin II - blood; Angiotensin II - urine; Angiotensin-(1-7); Animals; Capillary zone electrophoresis; Chemistry; Chromatographic methods and physical methods associated with chromatography; Electrophoresis, Capillary - economics; Electrophoresis, Capillary - methods; Exact sciences and technology; Hydrogen-Ion Concentration; Hypertension; Hypertension - blood; Hypertension - urine; Limit of Detection; Linear Models; Male; Other chromatographic methods; Peptide Fragments - blood; Peptide Fragments - urine; Rats; Rats, Wistar; Temperature; Hypertension; Capillary zone electrophoresis; Angiotensin II; Angiotensin-(1-7); Plasma; Temperature; Chemical analysis; Zone electrophoresis; Peptides; Rat; Time; Boric acid; Chlorides; Detection limit; pH; Quantitative analysis; Tool; Urine; Electrolyte solution; Capillary electrophoresis; Liquid electrophoresis; Use; Rodentia; Gold III; Concentration; Photodiode; Tartaric acid; Wavelength; Array; Vertebrata; Mammalia; Ultraviolet detector; Treatment; Reproducibility; Simultaneous measurement; Analytical method
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2009.10.010

We describe the procedure developed for the simultaneous detection and quantification of angiotensin II and angiotensin-(1-7), by capillary zone electrophoresis with UV detection by photodiode-array, at a wavelength of 200 nm, in the plasma and urine from hypertensive rats. Optimal separation was achieved with a 100 mM boric acid + 3 mM tartaric acid + 10 fM gold (III) chloride electrolyte solution at pH 9.80. The applied voltage was 30 kV and the capillary temperature was kept constant at 20 °C. The method was over the concentration range of 0.01–500 pmol/mL. All determination coefficients were higher or equal to 0.9985. Limits of detection and quantification for angiotensin II were 0.0110 pmol/mL (S/N = 3) and 0.0195 pmol/mL (S/N = 5), respectively. While for angiotensin-(1-7), the limits were 0.0112 pmol/mL (S/N = 3) and 0.0193 pmol/mL (S/N = 5), respectively. The present method offers a time-saving way to simultaneous determination of angiotensin II and angiotensin-(1-7), since it can be completed in 10 min, compared to other methodologies reported in the literature for capillary electrophoresis and liquid chromatography, which require more than 1 h for analysis of complex matrices, such as plasma and urine. The procedure is illustrated by experiments that quantify simultaneously angiotensin II and angiotensin-(1-7) in plasma and urine from hypertensive and normotensive rats, with and without antihypertensive treatment. The levels of angiotensin II and angiotensin-(1-7) detected in the experimental model, resulted in a recovery of 99.00–106.01% and a reproducibility of less than 10%. The proposed analytical method is a use full tool for the simultaneous detection of angiotensin II and angiotensin-(1-7) implicated in vascular remodeling in pathologies such as hypertension.