Nanodiamonds stabilized in dihexadecyl phosphate film for electrochemical study and quantification of codeine in biological and pharmaceutical samples

A new architecture for a sensor and a voltammetric procedure were proposed, using a glassy carbon electrode modified with nanodiamonds and dihexadecyl phosphate for determination of codeine (COD) in pharmaceutical and biological fluid samples. Square-wave voltammetry (SWV) was used and the relevant experimental parameters were optimized. Under optimal experimental conditions, the analytical curve presented a linear concentration range from 0.299 to 10.8 mu mol L-1, and a limit of detection of 54.5 nmol L-1. The proposed voltammetric method was used for COD determination in commercial pharmaceutical and biological fluid samples such as urine and human serum with satisfactory results. (C) 2017 Elsevier B.V. All rights reserved. (AU)