Vcx 750 sonicator

Ultrasound mixing was performed using sonics vibra-cell VCX 750 sonicator with 70% of nominal power. Mixing of the CNT/THF solution with polymer was performed using Heidolph MR-HEI Standard magnetic stirrer. The fiber was formed using a purpose designed screw extruder, equipped with two independently regulated heating zones, as presented in Figure 1. In this system, the speed of the screw is constant and set at 38 rpm, while the heating zones temperatures may be adjusted in the range from 25 to 500 °C. The system enables also the change of nozzle diameters.

The cells were incubated with formaldehyde at a final concentration of 1% for 10 min at 37°C to crosslink proteins and DNA. Crosslinking was terminated by treating the cells with glycine at a final concentration of 0.125 mol/L for 5 min at room temperature. The cells were collected and disrupted using a VCX750 sonicator (SONICS, USA) at an amplitude of 25%, pulse on for 4.5 s, and pulse off for 9 s for a total of 14 cycles. The cell lysate was centrifuged at 10,000 × g for 10 min at 4°C, insoluble material was removed, and the supernatant was collected. The specific antibody protein A agarose/salmon sperm DNA was used to bind to DNA-binding proteins, and the complexes were separated by precipitation. DNA was released and the proteins were digested by reverse crosslinking. The ZP1, ZP2, and ZP3 promoter fragments were detected by PCR as described above.