Spectrophotometric methods for the determination of urea in real samples using silver nanoparticles by standard addition and 2nd order derivative methods

In this work, we have developed simple, sensitive and inexpensive methods for the spectrophotometric determination of urea in urine samples using silver nanoparticles (AgNPs). The standard addition and 2nd order derivative methods were adopted for this purpose. AgNPs were prepared by chemical reduction of AgNO3 with hydrazine using 1,3-di-(1H-imidazol-1-yl)-2-propanol (DIPO) as a stabilizing agent in aqueous medium. The proposed methods were based on the complexation of AgNPs with urea. Using this concept, urea in the urine samples was successfully determined spectrophotometric methods. The results showed high percent recovery with +/- RSD. The recoveries of urea in the three urine samples by spectrophotometric standard addition were 99.2% +/- 5.37, 96.3% +/- 4.49, 104.88% +/- 4.99 and that of spectrophotometric 2nd order derivative method were 115.3% +/- 5.2, 103.4% +/- 2.6, 105.93% +/- 0.76. The results show that these methods can open doors for a potential role of AgNPs in the clinical determination of urea in urine, blood, biological, non-biological fluids. (C) 2017 Elsevier B.V. All rights reserved.