Advances in microfluidics and imaging, combined with some high-profile studies, are increasing interest in whole-organism screening.
Microfluidics for all sorts of manipulations and organisms. Hang Lu of Georgia Institute of Technology has developed systems that combine microfluidics with imaging, focusing on D. melanogaster embryos and C. elegans, making microfluidics system that moved a worm into place, immobilize it for imaging and even sort the worms by phenotype. Automated imaging allowed quantitative rather than qualitative assessments of parameters such as worm movement—something manual techniques are often too variable to do. The human eye is very good at pattern detection but less well when the organisms cannot be examined side by side. For subtle differences, such as slight differences in size or brightness, computers can give much more quantitative data, Lu says.
But both the microfluidics and imaging aspects for whole-organism phenotyping are still very much developing technologies, Lu says, and evaluate robustness needs attention – when processing a thousand samples. And it is not appropriate to calculate throughput by multiplying the number of samples by how long a platform takes to run one sample. Parameters such as how long the machine can run at a stretch, and how often a sample run fails must also be considered.
Monya Baker, Screening: the age of fishes, Nature Methods, Vol 8 No 1 Jan 2011