Development and characterization of a non-enzymatic electrochemical biosensor for rapid determination of sorbent-based extracted trazodone and doxepin in complicated samples.

BACKGROUND: Given the importance of achieving optimal therapeutical concentration in patients treated with antidepressants, this study investigates a novel technique for the simultaneous determination of trazodone (TRZ) and doxepin (DOX) in human plasma and serum samples for the first time. RESULTS: To achieve simultaneous determination of two antidepressants, TRZ and DOX, a novel detection system was designed: a non-enzymatic voltammetric biosensor based on boron-reduced graphene oxide/manganese oxide nanoparticles (GCE/B-rGO/MnO NPs). The detection was accomplished after pre-concentration and extraction trace amounts of the analytes using the thin film-solid phase microextraction (TF-SPME) technique, which employed polyvinyl alcohol/polyvinyl acetate/copper oxide nanoparticles (PVA/PVAc/CuO NPs) electrospun nanofibers. The successful preparation of composite nanofibers and modified electrodes was confirmed using the evaluation of field emission-scanning electron microscopy (FE-SEM) and energy-dispersive X-ray spectroscopy (EDX). Also, the composite nanofibers were characterized with attenuated total reflectance-Fourier transform-infrared (ATR-FT-IR) and X-ray diffraction (XRD). In the solution of TRZ and DOX, under optimum experimental conditions, the linear dynamic ranges (LDRs) were 0.1-20.0 µmol L-1 and 0.5-27.0 µmol L-1, respectively. Also, the limit of detection (LOD) values of TRZ and DOX were 0.032 and 0.150 µmol L-1. SIGNIFICANCE: PVAc acts as a cross-linking agent for PVA, and their mixture is effective for sample preparation and pre-concentration of analytes in complex matrices. Also, adding CuO NPs to this polymeric mixture enhanced the adsorption efficiency. Taking advantage of the high surface area of MnO NPs and the high electrical conductivity of B-rGO, and considering the superiority of their simultaneous utilization, the constructed electrochemical biosensor is both cost-effective and rapid. It demonstrates excellent stability, repeatability, and sensitivity for the simultaneous determination of TRZ and DOX under optimal conditions. This biosensor, the first of its kind, is specifically designed for the simultaneous determination of TRZ and DOX in human plasma and serum samples, representing a significant advancement in biosensing technology.

Association between quantitative morphological traits and RAPD molecular markers in pomegranate (Punica granatum L.).

Pomegranate (Punica granatum L.) is very important in terms of horticulture and food around the world. The present research aimed to identify the random amplified polymorphic DNA (RAPD) markers associated with morphological traits in pomegranate genotypes. Significant differences were observed among the studied genotypes based on the recorded traits. The 18 RAPD primers produced a total of 154 polymorphic fragments among genotypes. Using multiple regression analysis between each of the morphological traits and 154 RAPD polymorphic bands, RAPD markers associated with each of the morphological traits were identified. In total, 11 markers showed significant correlations with fruit weight, 9 markers with 100-aril weight, 11 markers with anthocyanin, and 8 markers with total soluble solids. Some markers were associated with more than one morphological trait, showing that the association of a marker with more than one trait can be caused by the pleiotropic effects of quantitative trait loci related to each other in different traits. For instance, the BA6-1 marker showed positive correlations with fruit weight, fruit crown width, and leaf length. Also, OPG13-3 and BA6-10 markers showed positive correlations with total soluble solids and anthocyanin content. The informative markers identified related to morphological characteristics in pomegranate can be a suitable guide to identify the genotypes with valuable fruit traits. Also, these markers can be used in selecting suitable parents for population generation for mapping purposes.