Preparation of imprinted polymers of dopamine, creatinine and fluoxetine bioactive molecules and investigation of potentiometric sensor behaviors

In this study, new type all solid-state potentiometric molecule selective microsensors were developed based on methacrylic acid based imprinted polymer of dopamine, creatinine and fluoxetine molecules. Dopamine, creatinine and fluoxetine as target molecules, methacrylic acid as functional monomer and ethylene glycol dimethacrylate as crosslinker were used for the polymer synthesis. The synthesized molecule imprinted polymers were used as ionophores to achieve a selective response in the polyvinylchloride membrane structure towards the main molecule. The potentiometric performance characteristics (linear range, detection limit, selectivity, slope, response time, pH range, lifetime, temperature range, etc.) of molecular selective microsensors were investigated. Prepared microsensors; showed potentiometric responses close to Nernst behavior for about 6 weeks over linear concentration ranges of 10-6-10-1 mol.L-1, 10-5-10-1 mol.L-1 ve 10-6-10-2 mol.L-1 with slope values of 60.26±1,3 mV (R2: 0.9998), 57.20±1,2 mV (R2: 0.9979) and 60.40±0,7 mV (R2: 0.9990) for dopamine, creatinine, and fluoxetine, respectively. The detection limits of the developed sensors were determined as 3.71x10-7 mol.L-1, 5.00x10-6 mol.L-1 and 1.87x10-7 mol.L-1 for dopamine, creatinine and fluoxetine, respectively. The response time of the microsensors was quite short (<15 sec). The pH working ranges of the microsensors were determined as 4.0-8.0, 6.0-10.0 and 4.0-7.0 for dopamine, creatinine and fluoxetine, respectively. The microsensors were successfully used for determinations of dopamine and fluoxetine in pharmaceutical drug samples, and the obtained potentiometric results for drug samples were statistically compared with the results obtained by the UV-vis spectrophotometric method at the 95% confidence level.