In vitro safety assessment of alkyl lactate esters in human umbilical vein endothelial cells (HUVECs).

Safety assessment requires information on both the chronic and acute effects of chemicals. Chemical materials such as food additives have become one of the most critical and compelling issues in the continuing debate on food safety. Calcium lactate (CL) and Sodium lactate (SL) are approved chemicals used in various products. The present study, in vitro study, was designed to evaluate the cyto-genotoxicity effects of CL and SL on human umbilical vein endothelial cells (HUVECs). The cytotoxicity effect of these additives was determined by MTT and Annexin V-FITC apoptosis assays. Besides, genotoxicity parameters such as morphological change of DNA and DNA fragmentation were studied with DAPI staining and DNA ladder assays, respectively. The results showed that the growth of HUVECs decreased upon treatment with CL at higher concentrations, but SL did not significantly alter HUVECs cell number. Annexin V-FITC apoptosis assays revealed that CL could induce cell death based on necrosis rather than apoptosis. In SL, the early and late apoptosis was not considerable in treated cells. Exposure to CL and SL did not lead to morphological change and DNA fragmentation in the HUVECs cell line. Overall, it is concluded from these results that CL and SL have not been cytotoxic and genotoxic effects in low concentrations in human umbilical vein endothelial cells in vitro.

Aptasensing of ciprofloxacin residue using graphene oxide modified with gold nanoparticles and branched polyethyleneimine.

Precise monitoring of antibiotic residues in aqueous solution is of vital significance for safeguarding the environment and food resources. Herein, a convenient platform was fabricated for the electrochemical assay of ciprofloxacin (CFX) in real milk samples using aminated aptamer and graphene oxide nanogold-functionalized branched polyethyleneimine (GO-PEI-AuNPs) nanocomposite. For the first time, a gold electrode was modified with GO-PEI-AuNPs. The modified surface endowed excellent electrochemical substrates with large surface areas, excellent electron transfer rates, and suitable capabilities to firmly attach high amounts of aptamer. After further modification of substrate with CFX specific aptamer a recognition probe enabling selective and sensitive determination of CFX was realized. All of the aptasensor fabrication steps were surveyed via cyclic voltammetry techniques. The construction and morphology of the GO-PEI-AuNPs composite were evaluated by UV-Vis spectroscopy, transmission electron microscopy, and field emission scanning electron microscopy. Under optimal conditions, the suggested scaffold can offer an acceptable linear range of 0.001 to 100 µM and a low limit of quantification of 0.001 µM for selective and sensitive monitoring of CFX in real samples. The effectiveness of the apta-assay was confirmed by detection of CFX in pasteurized and local milk samples for which suitable analytical results were achieved. It is expected that the developed substrate can be facilely extended to other aptamer-based multiplex screening platforms in actual food and environmental samples.

Sensitive aptasensing of ciprofloxacin residues in raw milk samples using reduced graphene oxide and nanogold-functionalized poly(amidoamine) dendrimer: An innovative apta-platform towards electroanalysis of antibiotics.

The constant need of humans and animals for food resources was led to overuse of antibiotics as vital medicines. In this regard, we are now facing major concern about the risks on the food safety and environment owing to their uncontrolled disposal. Hence, the progress of simple and sensitive approaches for fast monitoring of antibiotic levels is highly desirable. Here, we aimed to describe a new sensitive and easy-to use strategy based on electrochemical single off apta-assay toward ciprofloxacin (CFX). A novel interface using 3D Au-PAMAM/rGO have been designed via full electrochemically technique on the surface of glassy carbon electrodes (GCE) and evaluated with cyclic voltammetry method. Firstly, rGO with large amount of active functional groups as substrate was fabricated on the GCE electrode. Thereby, the 3D Au-PAMAM nanocomposite was synthesized and covalently electrodeposited onto the rGO-GCE modified surface. The structure and morphology of 3D Au-PAMAM were studied using UV-Vis spectroscopy, Field emission scanning electron microscopes (FE-SEM) and Transmission electron microscopy. Also, FE-SEM and Energy-dispersive X-ray spectroscopy (EDS) have been carry out to illustrate surface morphology of electrodes. The obtained results from square wave voltammetry, different pulse voltammetry, and chronoamperometry techniques implied that the suggested scaffold could be used as facile bio-device toward antibiotic detection with low limit of quantification (LLOQ) of 1 nM and a linear range of 1 µM-1 nM. Interestingly, the suggested aptasensor is successfully used to measure CFX residues in local and pasteurized milk samples. It can be deduced that Apt/rGO/3D Au-PAMAM/GCE as a novel biocompatible interface could offer suitable, cost-effective, reliable, rapid, and user-friendly sensing device for direct determination of CFX in real samples.