Flow Cytometry
entered high throughput drug screening laborato- ries, where typically 100,000s of samples are run in low volume microplate-based assays. Flow cytometry, in the past, has been severely limited in throughput rates of individual discrete samples, with sample times of several minutes per well. Typical 96-well microwell plate read times obtained with the Beckman Coulter FC500 auto- mated system (Figure 1) were at least 60 minutes or longer per plate depending on the assay. Some instruments, such as Becton Dickinson’s LSRII or Fortessa with the high throughput sampling attachment (HTS), have a slightly higher sampling rate, but collectively this low plate processing time was a significant limitation and could not meet the size and scale of assays run in drug screening labo- ratories. Even testing small (1,000s) compound- focused screening libraries was a challenge. The main features of conventional flow cytome- try that hamper their ability to handle samples rap- idly is a combination of data processing and the mechanics concerned with running one sample to the next. There are significant delays relating to saving individual sample associated files, and in the cell suspension sampling mechanism, that often involves tube priming and flushing11. Two succes- sive generations of high throughput flow cytome- try sample handling technology have evolved to address these issues. Both were developed at the University of New Mexico11. The first of these is Plug flow cytometry. A flow injection analysis approach is used in which individual sample sus- pensions are sequentially inserted as plugs of pre- cisely defined volumes into a flowing fluid, which delivers them into the flow cytometer12. The sec- ond generation technology, now commercialised by Intellicyt is the HyperCyt. This uses a peristaltic pump in combination with an auto-sampler (Figure 3). In contrast to the typical sample han- dling mechanism, the HyperCyt approach is to continuously deliver the entire sample, eg 96 wells, with each sample (well) separated by air bubbles (Figure 3). The data from all the samples in the plate are acquired and stored in a single file. A high resolution time parameter is also recorded during data acquisition. Temporal gaps in cell detection are created in the data stream by the passage of the air bubbles, allowing the individual cell suspen- sions to be easily distinguished and separately eval- uated when measured in conjunction with the time parameter. Cell suspension volumes as low as 1 to 2ul can be sampled depending on the cell concen- tration. The HyperCyt is compatible with a num- ber of different flow cytometers and the system can be automated with plate loaders. We took the
Drug Discovery World Spring 2013
Think outside the plate.
Billions of samples processed in Array Tape™
Imagine what this means for you.
Volume range: 0.5 - 25.0 uL
Array Tape™ is a microplate replacement in the form of a continuous polymer strip, serially embossed with reaction wells in customized volumes and formats including 96- and 384-well arrays.
www.DouglasScientific.com Array Tape applications limited only by imagination.
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80