Author(s): Saad S.M. Hassan
Article publication date: 1987-12-01
Vol. 5 No. 3 (yearly), pp. 319-326.
162
Keywords
lidocaine, ions, electrode
Abstract
A new lidocaine responsive liquid membrane electrode based on the use of lidocaine reineckate ion pair complex in nitrobenzene solvent is developed. The electrode displays a linear response for 10^-2 -10^-5M lidocaine over the pH range of 3-6.5. The response time varies from 35 sec to one min depending on the lidocaine concentration. The life span of the electrode is at least 1 month. Excipients and diluents commonly used in local anesthetic formulations do not interfere. Determination of lidocaine in some pharmaceutical preparations gives results with an average recovery of 99% of the nominal values and a mean standard deviation of 1.7% which compare favorably with those obtained by the United States Pharmacopoeia method.