Synthesis and Application of the Magnetic Nanocomposite GO-Chm for the Extraction of Benzodiazepines from Surface Water Samples Prior to HPLC-PDA Analysis

Abstract

Nowadays, the interest in preparing new, cheap and simple adsorbents that are used in sample preparation is on the rise. Graphene oxide (GO) nanomaterials and nanocomposites have become increasingly popular due to the novel methods of syntheses that have been published. Owing to their vast specific surface area and their π-delocalized electron system they possess, they are appropriate for the adsorption of a variety of aromatic organic compounds, being utilized either as adsorbents in analytical methods or as filter materials for the removal of pollutants in water. Pharmaceutical compounds, such as benzodiazepines, end up in surface waters caused by consumption or their disposal through sewage, thus becoming pollutants. In the present study, an analytical method has been developed and validated for the determination of two model-analytes of benzodiazepines by HPLC-DAD and their sample preparation protocol which consists of the Stir bar magnetic solid phase extraction (SB-MSPE) method, evaluating therefore the nanocomposite material as a decent adsorbent. The separation took place with the usage of an analytical column C18 RP-HPLC in 10 min. For the alprazolam (ALP) and the flunitrazepam (FLT), the LODs and LOQs were 3 ng/mL and 10 ng/mL, respectively, while the relative recoveries ranged between 93.6–112.9% and the RSDs were 1.11–9.50%. Finally, the material was examined for its reusability and was found that it can be used for over eight cycles of extraction/elution.

Extraction of alprazolam in biological samples using the dispersive solid‐phase method with nanographene oxide grafted with α‐pyridylamine

“…For elution solvent volume shown in Figure 7 ., more than 10 ml, all of the alprazolam molecules enter the elution solvent, the equilibrium shifts to the elution solvent's side, and a complete desorption occurs. As a result, the optimum volume for alprazolam was determined to be 10 ml [ 21 ].…”

“…In another last research with graphene oxide/magnetic chitosan nanocomposite, the alprazolam was extracted. The LOD of this method is 3000 ng/l in 10 min time of the test [ 21 ]. The current study with the lowest LOD and 5 min analysis test is a good process for the extraction of alprazolam.…”

“…Therefore, the remaining amount that is not absorbed, or their metabolites, are released into the environment through urine or faeces and end up in sewage waterways. Some of it is found in surface water samples because wastewater treatment facilities are unable to completely remove it from the water [ 21 , 22 ].…”

Benzodiazepines in complex biological matrices: Recent updates on pretreatment and detection methods

“…Plastiras et al. [ 107 ] selected a nanocomposite of GO with magnetic chitosan (GO-Chm) as an adsorbent for extracting BDZs from surface water. The recoveries of two target analytes ranged from 93.6% to 112.9% under optimized conditions.…”

Comparison of Structure and Magnetic Properties of Ni/C Composites Synthesized from Wheat Straw by Different Methods

“…Secondly, metal nano-powders undergo processes of spontaneous agglomeration, which leads to the loss of some unique physicochemical properties and complicates their further application. The composites which use transition metals, their oxides or hydroxides as the active substances, are widely used as catalysts, devices for recording and storing information, active materials for supercapacitor electrodes and magnetically sensitive adsorbents [1][2][3][4][5][6][7][8].…”