In-situ electromechanical testing and loading system for dynamic cell-biomaterial interaction study.

The mechanical and electrical properties of biomaterials are essential in cell function regulation during cell-biomaterial interaction. However, previous studies focused on probing cell regulation mechanisms under one type of stimulus, and a platform that enables the study of electromechanical coupling effects of a biomaterial on cells is still lacking. Here, we present an in-situ electromechanical testing and loading system to image live cells when co-cultured with electroactive biomaterials. The system can provide accurate and repeatable stretch on biomaterials and cells to mimic in vivo tension microenvironment. Besides, the integrated displacement transducer, force sensor, and electrical signal detector enable the real time detection of electromechanical signals on electroactive biomaterials under various stretch loading. Combined with a microscope, live cell imaging can be realized to probe cell behavior. The feasibility of the system is validated by culturing mesenchymal stem cells on piezoelectric nanofiber and conductive hydrogel. Experiment results show the device as a reliable and accurate tool to investigate electromechanical properties of biomaterials and probe essential features of live cells. Our system provides a way to correlate cell behavior with electromechanical cues directly and is useful for exploration of cell function during cell-biomaterial interaction.

Synthesis of nano-zirconium-iron oxide supported by activated carbon composite for the removal of Sb(v) in aqueous solution.

In this study, nano zirconium iron oxide based on activated carbon (ZIC) was successfully prepared by using the coprecipitation method. Compared with unmodified activated carbon, ZIC increases the number of active sites by adding metal oxides and hydroxyl groups and greatly improves the adsorption capacity of Sb(v). The synthesized nanocomposites were characterized and analysed by XRD, SEM, FT-IR, VSM and other techniques. The results showed that the zirconium iron oxide particles were successfully loaded and uniformly distributed on the surface of the activated carbon, and the agglomeration phenomenon was reduced. The saturation magnetization of ZIC was 1.89 emu g-1, which easily achieved solid-liquid separation under the action of an external magnetic field. In batch experiments, when the initial concentration was 1 mg L-1, the dosage of ZIC was 600 mg L-1, the pH value was 5.0, the contact time was 180 min, and the removal rate of Sb(v) reached 97.82%. The maximum adsorption capacity of ZIC for Sb(v) was 11.80 mg g-1. Under the interference of various inorganic ions and dissolved organics, the excellent adsorption capacity was still due to ZIC. The adsorption form was multimolecular-layer adsorption, the adsorption process was an endothermic reaction, and chemical adsorption was dominant as the adsorption mechanism. ZIC has good removal efficiency and is reusable, which indicates that ZIC has prospects for practical wastewater treatment.