simultaneous determination of trazodone and doxepin as antidepressant drugs in human plasma samples with new voltammetric biosensor (gce/b-rgo/mno nps)

Aim and background: despite of the antidepressant drugs therapeutic performance, they may have side effects and high dosage of them may make toxicity in human body. thus, measurement of trace amounts of these drugs in complex matrices such as, biological fluid samples is very important.methods: herein, trazodone (trz) and doxepin (dox) were determined simultaneously with a non-enzymatic voltammetric biosensor based on glassy carbon electrode/ boron-reduced graphene oxide/ manganese oxide nanoparticles (gce/b-rgo/ mno nps). due to advantages of the wide special surface area of mno nps and the high electrical conductivity of b-rgo, the constructed electrochemical biosensor shows high sensitivity for the simultaneous determination of trz and dox at optimum conditions.results and discussion: from the evaluation of field emission scanning electron microscopy (fe-sem), fourier transform infrared (ft-ir) spectroscopy, and energy dispersive x-ray (eds), the successful synthesis of b-rgo/ mno nps was approved. the effective factors on the electrochemical biosensor were optimized with the one at a time (oat) method. under the optimum conditions, in the mixture of trz and dox, the linear response ranges were 10 µm to 400 µm and 150 µm to 450 µm, respectively. also, the low limit of detection (lod) values of trz and dox were obtained at 3 µm and 45 µm, respectively. this biosensor is specially designed for simultaneous measurement of trz and dox in human blood plasma samples. under the optimum conditions, good recoveries were obtained.conclusion: in this research, the sensitive and novel diagnostician of two anti-depressant drugs was done, simultaneously, for first time with a fast and nonenzymatic electrochemical biosensor in the human fluidal samples.