Determination of carnosic acid in Rosmarinus officinalis L. using square wave voltammetry and electrochemical behavior

Abstract

A new, fast, sensitive and simple voltammetric method is established for the direct determination of carnosic acid (CA). And the electroreduction of carnosic acid (CA) was studied using electrochemical methods. The number of electrons transferred in electrode mechanisms were calculated for reversible and adsorption-controlled electrochemical reduction of CA at 17 mV versus Ag/AgCl at pH 7.0 in Britton-Robinson buffer (BR) on a hanging mercury drop electrode. Square-wave voltammetry was developed and validated for direct determination of CA. Square-wave parameters were optimized as accumulation potential = 0.0 mV, accumulation time = 5 s, frequency = 50 Hz, pulse amplitude = 50 mV, and staircase step potential = 5 mV. The developed method displays three linear responses from 2 to 9 μM, 10 to 30 and 40 to 90 μM for carnosic acid with a correlation coefficient of 0.996, 0.999 and 0.999. The detection limits were found to be 1.5 μM, 4.0 μM and 40.1 μM, respectively. The interference effect of most common organic and inorganic species was investigated. Proposed method was successfully applied for determination of CA in natural extract of rosemary and the average content was determined as 11.9 ± 1.0 (μg CA/1 g rosemary). The results were in agreement with that obtained by HPLC-UV comparison method. The developed method can be widely used in routine quality control of herbal materials as well as other in foods, medicinal, pharmaceutical and environmental analysis.

Carnosic Acid and Carnosol: Analytical Methods for Their Determination in Plants, Foods and Biological Samples

“…Yilmaz et al studied the electrochemical behavior of carnosic acid and based on their findings, developed a square-wave voltammetric method for the determination of carnosic acid in rosemary extracts. This method displayed good linear responses and the results are in good agreement with an HPLC-UV method [99].…”

“…Two less-explored techniques that were applied for the analysis of diterpenes such as carnosic acid are UV spectrophotometry and square-wave voltammetry (SWV) [98,99]. The former was utilized for the quantitative determination of the diterpenes extracted from garden sage leaves.…”

Investigating the Relationship between Antioxidants and Fatty Acid Degradation Using a Combination Approach of GC-FID and Square-Wave Voltammetry

“…For RE, the smaller oxidation current and broader peak are likely a result of competing reversible oxidation–reduction currents due to the different species that comprise rosemary extract. It has been shown that both carnosic and rosmarinic acid, which are the primary components of rosemary extract, produce reversible electrochemical properties when subjected to anodic and cathodic currents. , BHT also shows a smaller current and a wider peak than sesamol, along with a broader decay slope, which could be partially due to the steric hindrance of BHT and sesamol.…”

“…It has been shown that both carnosic and rosmarinic acid, which are the primary components of rosemary extract, produce reversible electrochemical properties when subjected to anodic and cathodic currents. 29,30 BHT also shows a smaller current and a wider peak than sesamol, along with a broader decay slope, which could be partially due to the steric hindrance of BHT and sesamol.…”