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Introduction:The gold standard for diagnosis of coronavirus disease 2019 (COVID-19) is detecting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by reverse transcription polymerase chain reaction (RT-PCR), which is expensive, time-consuming and may result in false-negative results. Serological tests can be employed for RT-PCR negative patients, contact tracing, determining the probability of protection against re-infection, and seroepidemiological studies. Areas covered: The main methodologies of serology-based tests for the detection of SARS-CoV-2 including enzyme-linked immunosorbent assays (ELISAs), chemiluminescent immunoassays (CLIAs) and lateral flow immunoassays (LFIAs) were reviewed and their diagnostic performances were compared. Herein, a literature review on the databases of PubMed, Scopus and Google Scholar between January 1, 2020 and June 30, 2020 based on the main serological methods for COVID-19 detection with the focus on comparative experiments was performed. The review was updated on December 31, 2020. Expert opinion: Serology testing could be considered as a part of diagnostic panel two-week post symptom onset. Higher sensitivity for serology-based tests could be achieved by determining combined IgG/IgM titers. Furthermore, higher sensitive serological test detecting neutralization antibody could be developed by targeting spike (S) antigen. It was also demonstrated that the sensitivity of ELISA/CLIAbased methods are higher than LFIA devices.

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Background and objectives: Although studies have elucidated the significant biomedical potential of biogenic metallic nanoparticles (MNPs), it is very important to explore the hazards associated with the use of biogenic MNPs. Evidence indicates that genetic toxicity causes mutation, carcinogenesis, and cell death. Materials and Methods: Therefore, we systematically review original studies that investigated the genotoxic effect of biologically synthesized MNPs via in vitro and in vivo models. Articles were systematically collected by screening the literature published online in the following databases; Cochrane, Web of Science, PubMed, Scopus, Science Direct, ProQuest, and EBSCO. Results: Most of the studies were carried out on the MCF-7 cancer cell line and phytosynthesis was the general approach to MNP preparation in all studies. Fungi were the second most predominant resource applied for MNP synthesis. A total of 80.57% of the studies synthesized biogenic MNPs with sizes below 50 nm. The genotoxicity of Ag, Au, ZnO, TiO2, Se, Cu, Pt, Zn, Ag-Au, CdS, Fe3O4, Tb2O3, and Si-Ag NPs was evaluated. AgNPs, prepared in 68.79% of studies, and AuNPs, prepared in 12.76%, were the two most predominant biogenic MNPs synthesized and evaluated in the included articles. Conclusions: Although several studies reported the antigenotoxic influence of biogenic MNPs, most of them reported biogenic MNP genotoxicity at specific concentrations and with a dose or time dependence. To the best of our knowledge, this is the first study to systematically evaluate the genotoxicity of biologically synthesized MNPs and provide a valuable summary of genotoxicity data. In conclusion, our study implied that the genotoxicity of biologically synthesized MNPs varies case-by-case and highly dependent on the synthesis parameters, biological source, applied assay, etc. The gathered data are required for the translation of these nanoproducts from research laboratories to the clinical market.

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Background:The periplasmic overexpression of recombinant human interferon beta (rhIFN-β)-1b using a synthetic gene in Escherichia coli BL21 (DE3) was optimized in shake flasks using Response Surface Methodology (RSM) based on the Box-Behnken Design (BBD).Objectives:This study aimed to predict and develop the optimal fermentation conditions for periplasmic expression of rhIFN-β-1b in shake flasks whilst keeping the acetate excretion as the lowest amount and exploit the best results condition for rhIFN-β in a bench top bioreactor.Materials and Methods:The process variables studied were the concentration of glucose as carbon source, cell density prior the induction (OD 600 nm) and induction temperature. Ultimately, a three-factor three-level BBD was employed during the optimization process. The rhIFN-β production and the acetate excretion served as the evaluated responses.Results:The proposed optimum fermentation condition consisted of 7.81 g L-1 glucose, OD 600 nm prior induction 1.66 and induction temperature of 30.27°C. The model prediction of 0.267 g L-1 of rhIFN-β and 0.961 g L-1 of acetate at the optimum conditions was verified experimentally as 0.255 g L-1 and 0.981 g L-1 of acetate. This agreement between the predicted and observed values confirmed the precision of the applied method to predict the optimum conditions.Conclusions:It can be concluded that the RSM is an effective method for the optimization of recombinant protein expression using synthetic genes in E. coli.