Sodium dodecylbenzenesulfonate–based silver nanoparticles and their potent application as antibiofilm,antimicrobial agent,and trace level determination of amlodipine

Herein, we presented the synthesis and application of sodium dodecylbenzenesulfonate–based silver nanoparticles (termed as SDBS-AgNPs). The SDBS reverse micelles (RMs) in ethanol was used as nanoreactor for green AgNPs synthesis. The size, structure, and shape of SDBS-AgNPs were well distinct by UV/visible (UV/Vis), Fourier transform infrared (FTIR) spectroscopy, dynamic light scattering (DLS), and atomic force microscopy (AFM) techniques. The SDBS-AgNPs were quite stable even at high temperature (80 °C), salt concentration (up to 300 μM), and wide pH range (2 to 12). Moreover, SDBS-AgNPs were found to be highly sensitive and selective colorimetric sensor for antihypertensive drug amlodipine (AML). The interaction of AML with SDBS-AgNPs resulted as a substantial increase in the absorbance and a prominent blue shift in wavelength from 426 to 400 nm. DLS results were further confirmed that the SDBS-AgNPs break into smaller sized particles. Similarly, FTIR results also verified the SDBS-AgNPs etching–based sensing of AML molecules due to the strong attraction by amine and carbonyl functional groups on the target drug. The proposed sensor exhibited linear response in the range of 0.001–200 μM (R² = 0.9917) with limit of detection (LOD) and quantification (LOQ) of 0.161 and 0.49 μM, respectively. The probe remained selective against AML, even in the presence of equimolar interfering species (including other drugs and metal ions). Furthermore, findings proposed that the SDBS-AgNPs might be used as effective substitute to minimize infection severity by obstructing the biofilm formation against nosocomial and urinary tract infection (UTI) causing pathogens.

Graphical abstract

     

Recombinant Human erythropoietin reduces viability of MCF-7 breast cancer cells from 3D culture without caspase activation

Recombinant human erythropoietin (rHuEPO) is the erythropoiesis-stimulating hormone that is being used concurrently with chemotherapeutic drugs in the treatment of anemia of cancer. The effect of rHuEPO on cancer cells in 3-dimensional (3D) cultures is not known. The objective of the study was to determine the effect of rHuEPO on the viability of MCF-7 breast cancer cells from 2-dimensional (2D) and 3D cell cultures. The monolayer MCF-7 cells from 2D culture and MCF-7 cell from 3D culture generated by ultra-low adhesive microplate technique, were treated with 0, 0.1, 10, 100 or 200 IU/mL rHuEPO for 24, 48 or 72 h. The effects of rHuEPO on MCF-7 cell viability and proliferation were determined using the (4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay (MTT), neutral red retention time (NRRT), trypan blue exclusion assay (TBE), DNA fragmentation, acridine orange/propidium iodide staining (AO/PI) assays. The MCF-7 cells for 3D culture were also subjected to caspase assays and cell cycle analysis using flow cytometry. rHuEPO appeared to have greater effect at lowering the viability of MCF-7 cells from 3D than 2D cultures.rHuEPO significantly (p < 0.05) decreased viability and down-regulated the caspase activities of 3D MCF-7 cells in dose- and time-dependent manner. The cell cycle analysis showed that rHuEPO caused MCF-7 cells to enter the subG0/G1 phase. Thus, the study suggests that rHuEPO has a cytostatic effect on the MCF-7 breast cancer cells from 3D culture.     

Exploring continuity equation via a modeling activity: in the context of crowd science

Abstract

Using problems from real life contexts which is related to learners’ environment or their culture plays an important role in their learning that concept. In this regard, science educators especially physics educators search for real-life domain of theoretical concepts for effective science teaching and they consider analogical and physical models as an opportunity in their instruction. In the presented activity, we worked with 66 senior pre-service science teachers from our science teaching methods course. We used crowd movements as a real-life domain of our analogical models to scientifically explain a stampede case, then utilized physical model to explore continuity equation. Real life problem based scenarios could be used while taking advantage of the 3?D modeling in teaching of scientific principle. As a result, we found that pre-service teachers were able to make scientific explanation for causes of stampedes by using modeling activity. High school teachers and upper-level instructors could benefit from including the modeling activity introduced in this study to help their students understand the concepts related to continuity equation by designing a physical model based on an analogical model. Via the physical model, students are able to make predictions, observations, interpretations and explanations of a complex and abstract scientific phenomenon.