MoFLo®

The MoFlo is a top of the line cytometer that combines the ultimate performance of a research sorter, with the ease of use of more limited systems. The MoFlo line consists of a series of models, each upgradeable to 3 laser, 12 parameter, and 25,000 cell/sec performance.

The modular flow cytometer systems have been designed to eliminate performance variability due to interdependent component adjustments. Independent optical paths allow simple adjustments for each beam. Maximum sort rates in excess of 25,000 cells per second are achieved by a proprietary jet in air nozzle that minimizes divergence from laminar flow conditions.

The fluidics system is designed to operate to 100 psi. Transport tubing is terminated in Swage-type connectors to enable rapid dismantling for sterilization or mechanical cleaning. Sample injection is designed to eliminate contamination. The sample injector is equipped with a 3-port inlet to facilitate kinetics experiments.

Sorting functions are controlled by the Cytomation Sort Unit. Drop drive fequencies up to 200KHz can be generated. The arbitrary waveshape crystal drive signal gives precise control of droplet formation and satellite reduction. Drop delay can be set from 10 to 99 drops with a 1/16th of a drop resolution. Asymmetric phase sensitive sorting provides optimum purity vs. recovery. Droplet charge is variable from 0 to +/- 200V, and includes precise de-emphasis for zero parasitic side streams. Charge phase control is continuously variable with a 1.4 degree resolution.

MoFlo's electronics are based upon a patented Parallel Pulse Processing algorithm that enables event recognition without limitation by the dwell-time of cells passing through a multiple laser array. The result is a sort rate conservatively rated at 25,000 cells per second.

The system incorporates a first-in-first-out (FIFO) buffer connected via a high speed (600 kbytes per sec) data bus to an external computer. The data bus is in the public domain to allow custom designed interface cards for on-line data monitoring and feedback.

Each PMT is served by a high speed ADC producing a 6 millisecond deadtime in both single and multiple beam modes. Signal resolution is 4096 channels for univariate histograms and 128 x 128 bivariate histograms. Ten analog signals can be acquired.