1. A novel and simple electrochemical sensor for some dopaminergic drugs such as selegiline and pramipexole based on a nickel nanoparticle modiﬁed carbon paste electrode
Reza Ojani,* Shahab Gholitabar Omrani, Jahan-Bakhsh Raoof and Saeed Zamani. Anal. Methods,2016, 8,2471–2478
Electrocatalytic determination of selegiline andpramipexole.
Since cyclic voltammetry is not sensitive for low concentrations of SEL and PX. In order to enhance the sensitivity of the method, constant potential amperometry under hydrodynamic conditions was used to detect the lower concentrations of SEL and PX. Fig. 8 shows a typical hydrodynamic amperometric response obtained by adding SEL to a continuously stirred 100 mV NaOH solution, which shows an increase in the current for successive increments of 5 mM SEL.
The inset of Fig. 10 illustrates the corresponding plot showing a linear relationship between the peak current and the SEL concentrations. This modified electrode exhibited similar concentration dependent profiles for PX. The analytical parameters are listed in Table 1. The applicability of the proposed amperometricmethod was examined by analyzing the plasma sample. The recovery of SEL and PX was measured by spiking SEL and PX into highly diluted plasma samples and the standard addition method was used to analyze the prepared samples. The quantity experimentally determined was compared to that of the spiking in plasma samples. The results are summarized in Table 2. Typical examples of amperograms are shown in Fig. 9.
2. A novel electrochemical sensor for non-ergoline dopamine agonist pramipexole based on electrochemically reduced graphene oxide nanoribbons
Prashanth S. Narayana, Nagappa L. Teradal, J. Seetharamappa* and Ashis K. Satpati. Anal. Methods,2015, 7,3912–3919
Pramipexole (PPX), chemically known as (6S)-N6-propyl-4,5,6,7-tetrahydro-1,3-benzothiazole-2,6-diamine, is an orally active, non-ergoline, azepine derivative. It is a dopamineagonist used for the treatment of restless legs syndrome and Parkinson's disease. PPX is a novel aminobenzothiazole compound having the highest aﬃnity towards D3-subtype dopamine receptors. PPX has an excellent oral bioavailability. Food does not influence the degree of absorption. A literature survey revealed that only one voltammetric method was reported for the assay of Pramipexole (PPX). However, the reported voltammetric method uses bismuth for electrode modification. Bismuth is known to cause kidney damage and other health risks and so its extensive use is not recommended. Moreover, the reported method is less sensitive (LOD=12.79 ng mL-1) and needs longer time for drying themodified electrode at room temperature. In view of this, we have used graphene oxide nanoribbons for the modification of the electrode and adapted an eco-friendly method for its reduction. The purpose of the present investigation is to develop an environmentally friendly, simple, sensitive and economically feasible sensor for the determination of Pramipexole (PPX) in tablets, human plasma and urine samples.