Comparative Electrochemical Studies of Modified 2-Hydroxypropyl Beta Cyclodextrin and Modified Carbon Nanotubes Sensors for Determination of Naloxone Hydrochloride

摘要

A simple, precise, accurate and sensitive electrochemical method for potentiometric determination of naloxone hydrochloride (NLX) was developed. The developed method was based on the incorporation of NLX with sodium tetraphenyl borate (TPB) to fabricate four NLX-TPB sensors using o-nitrophenyloctyl ether (o-NPOE) as a plasticizer in a polymeric matrix polyvinyl chloride (PVC). Sensor I and sensor II were conventional plastic membrane type, while sensor II was modified using 2-hydroxypropyl beta cyclodextrin (β-CD) as an ionophore. Sensor III and sensor IV were carbon paste type and sensor IV was modified using carbon nanotubes (CNTs). The optimum conditions were investigated and characterized. They displayed Nernstian responses of 54.2±0.4 and 56.4±0.8, 57.0±0.5 and 58.1±0.2 mV decade~(-1) for sensors I, II, III and IV, respectively at 25℃ over drug concentration ranges of 1.0 × 10~(-5) - 1.0 × 10~(-3) and 1.0 × 10~(-6) - 1.0 × 10~(-2) mol L~(-1), 1.0 × 10~(-7) - 1.0 × 10~(-2) and 1.0 × 10~(-8) - 1.0 × 10~(-2) mol L~(-1) with lower detection limits of 5.0 × 10~(-6), 6.3 × 10~(-7) and 3.9 × 10~(-8) and 5.0 × 10~(-9) mol L~(-1) for the four mentioned sensors, respectively. The selectivity of the proposed method towards the investigated drug and some possible interfering species was studied using a separate solution method. The developed method was validated and gave excellent results for determination of NLX in its pharmaceutical formulation and biological fluids.