An improved drop casting electrochemical strategy for furosemide quantification in natural waters exploiting chemically reduced graphene oxide on glassy carbon electrodes

• Published in: Analytical and bioanalytical chemistry Vol. 412; no. 26; pp. 7123 - 7130
• Main Authors: Vasconcelos, Sancler C., Rodrigues, Eduardo M., de Almeida, Leonardo G., Lepri, Fábio G., Pacheco, Wagner F., Semaan, Felipe S., Dornellas, Rafael M.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-10-2020; Springer; Springer Nature B.V
• Subjects: Acetates; Acetic acid; Analysis; Analytical Chemistry; Biochemistry; Carbon - chemistry; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Chromatography, High Pressure Liquid - methods; Diuretics - analysis; Electrical measurement; Electrochemical Techniques - methods; Electrochemistry; Electrodes; Electrolytes; Food Science; Furosemide; Furosemide - analysis; Glassy carbon; Graphene; Graphite; Graphite - chemistry; High performance liquid chromatography; Ions; Laboratory Medicine; Limit of Detection; Liquid chromatography; Monitoring/Environmental Analysis; Natural waters; Oxidation-Reduction; Pharmaceutical industry wastes; Pollutants; Recovery; Reproducibility of Results; Research Paper; Spectrophotometry, Ultraviolet - methods; Water Pollutants, Chemical - analysis; Brazil; Amperometry; GCE; CRGO; BIA; Furosemide; Seawater
• ISSN: 1618-2642; 1618-2650
• DOI: 10.1007/s00216-020-02845-9

This work exploits the applicability of a chemically reduced graphene oxide (CRGO) modification on the electrochemical response of a glassy carbon electrode (GCE) for the first-time sensitive determination of furosemide in natural waters. The batch injection analysis (BIA) is proposed as an analytical method, where CRGO-GCE is coupled to a BIA cell for amperometric measurements. Acetate buffer (0.1 μmol L
−1
, pH 5.2) was used as the background electrolyte. The modification provided an increase in sensitivity (0.024 μA/μmol L
−1
), low limit of detection (0.7 μmol L
−1
), RSD (< 4%), and broad linear range (1–600 μmol L
−1
). Recovery tests performed in two different concentration ranges resulted in values between 89 and 99%. Recovery tests were performed and compared with high-performance liquid chromatography (HPLC) with UV-Vis detection using Student’s
t
test at a 95% significance level, and no significant differences were found, confirming the accuracy of the method. The developed method is proven faster (169 h
−1
) compared with the HPLC analysis (5 h
−1
), also comparable with other flow procedures hereby described, offering a low-cost strategy suitable to quantify an emerging pharmaceutical pollutant.
Graphical abstract