At long, long, last - Mosquitoes Meet Microfluidics. The vectorChip is on bioRxiv. A short thread. 1/n https://www.biorxiv.org/content/10.1101/2020.10.19.345603v1

I moved to @PrakashLab in 2015 to 'do genomics on single mosquito bites' with Haripriya - basic idea: characterize the genomic content of saliva droplets coming from single mosquito bites. Like this:
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1. get mosquitoes excited about a microfluidic chip.
2. persuade mosquitoes to bite on-chip microscopic wells and spit saliva into the wells.
3. add reagents to the on-chip wells, run multiplexed PCR.
4. image chip and decipher genomic content of individual mosquito bites.
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Sounds simple (2015).

Trail and (LOTS of) error....
and more error.
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why is this hard?
Finding a material that 1) mosquitoes like & can bite through, and 2) can withstand high temperatures and pressures (for on-chip PCR) turned out the be HARD. Either the mosquitoes were too picky, or the PCR too demanding...
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fast forward year(s) @shailabhk brought new perspectives and skills to the project resulting in a wonderfully thin PDMS membrane that, with some downstream tweaks, satisfied our criteria - mosquitoes bit and spit through, and the PCR worked!!
The vectorChip was born.
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awesome thing: this membrane can be integrated with (almost) any microfluidic geometry, paving the way to do all kinds of assays on mosquito spit (what else to wish for?)
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Once the membrane worked we could test it with various species of mosquitoes, including Zika virus infected Ae aegypti. Mosquitoes feasted on the chip for 20 minutes resulting in plenty of mosquito DNA and Zika RNA positive wells.
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Taking it one level further @sujitpujhari @shailabhk and @vectorgen even cultured cells in the chips to do focus forming assays straight from mosquito bites. Live Mayaro virus detected directly from mosquito bites on the vectorChip!
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This project continues and the hope is that one day it will become what we set out for in 2015: a tool that enables field ecologists to screen natural populations at 'single mosquito resolution'. This manuscript is a first step in that direction.
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Appendix:
One cool thing we did along the way: Imaging fluorescent saliva being expectorated. Mosquito spit = beautiful.

all dots in the image are saliva droplets (unfortunately Twitter errors on a high-resolution version....)