With unipolar square wave or single square pulse, the membrane is permeabilized either on one side or asymmetrically. TOFD, and conventional probes with the bipolar square wave initial pulse. Pulser type Bipolar square, unipolar positive, unipolar negative square wave Pulse voltage 15 V to 100V, 1V Step Pulse width Unipolar pulse width 25 ns to 500 ns, 5ns step Bipolar pulse width 50 ns to 1 s, 5 ns step Damping Active Pulser output impedance 8 Ohm (typical) Pulse Rise time 5 ns V-100V (typical) Pulse Fall time 11 ns.
#UTPOD. BIPOLAR SQUARE WAVE PULSER GENERATOR#
This generator is capable of producing both positive and negative going square waves with variable amplitude, repetition rate, and width. instrument ISONIC utPod for PC Software Package Latest update:.
#UTPOD. BIPOLAR SQUARE WAVE PULSER FULL#
Qualitative comparison of cell permeabilization induced by the three types of wave forms and monitored by ethidium bromide uptake revealed that only the bipolar square wave permeabilizes the cell membrane symmetrically at the two hemispheres facing the electrodes. The construction of a high-voltage (up to 1000 V) bipolar metal-oxide-semiconductor field-effect transistor square-wave generator is described. The average of a sine wave over one half-cycle: Consider a sine wave of peak amplitude I p and frequency f: I(t)I p sin(2f t) I p sin(t) (1.3) The period of the wave,, is given as: 1 2 f (1.4) The average value of one half-cycle in time, is then calculated as: ( ) ( ) ( t) dt I I I t dt. ISONIC utPod delivers full functionality of the top performance ultrasonic flaw detector such as: Bi-polar square wave pulser with tunable shape, pulse duration and amplitude (up to 300 V pp) and boosted leading / falling edges enhancing ultrasound penetration for various materials characterized either by high or low grain, sound attenuation, and the like 100 dB analogue gain / 0.2. re-define) the starting time, t1 of this waveform to be t1 0. In the range of electric field strength used for optimum transfection, the survivability of electropermeabilized cells was comparable between the unipolar and bipolar square waves but fell considerably with the single square pulse. Fourier Analysis of a Periodic, Symmetrical Square Wave A temporally-periodic, bipolar square wave of unit amplitude and 50 duty cycle is shown in the figure below: Since this waveform repeats indefinitely, then, without any loss of generality we can arbitrarily choose (i.e. Results show that a bipolar square wave is, at least, 1.7- and 5.5-fold more efficient than the unipolar square wave and single square pulse, respectively. Using the plasmid DNA pSV2-neo (which, when integrated into the cellular genome confers resistance to the antibiotic G418 for selection), we examined and compared the transfection efficiency on NIH 3T3 cells electropermeabilized by applying a sequence of high-frequency unipolar or bipolar square waves or a single square pulse.
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