Hey, I just came across this idea that sounds really cool in theory, but I'm wondering if anyone out knows if it's actually technically possible:

Lab-on-a-chip detectors http://marblar.com/challenge/Micro-mixer/idea/1237

So the analyte is passively mixed by a tiny microfluidic mixer which is then passed onto the chip that detects DNA.This apparently would be a much faster process than the current system.

However, I have doubts that this is necessary because they are already doing this without the mixing device. What do you guys think?

I am not sure what you mean with detecting DNA. What part of the DNA? Detecting, or sequencing/amplification?

 

In any case there are already plenty of lab on a chip (LOC) devices that manipulate, amplify, quantify and even sequence DNA (some are commercially available). Mixing is really only needed if the reaction volumes are larger, but in many chip devices the reaction chambers are small enough so that diffusion is sufficient.

Also note that there are many options for actual on-chip mixing. The whole idea of LOC is that it integrates as many steps as possible within a single device.

Edited June 28, 201312 yr by CharonY

Yeah I needed to be more specific - identifying DNA through DNA hybridisation.

 

Yes there are a huge number of LOC devices, could you see any advantage to adding this mixer to a LOC? or anywhere else? A bit of background research and I've found that slow diffusion kinetics is apparently a problem in bioassay, so if it's possible to mix the regent and sample efficiently beforehand using this device then it could lead to faster detection (as there is a faster reaction).

I would not think that it is a problem. For a well-controlled hybridization temperature control is in the small volume (say, picoliter range) is good enough (too strong agitation is potentially detrimental at this step). You should also note that often hybridizations are more efficient in immobilized assays, whenever possible. Also there are droplet based assays that have excellent volume control. That being said, for some situations where volume is larger and/or fast buffer and mixing is relevant, or where gradients are desired there are quite a few options already on the market. Some include (3d) diffusive mixing, manipulations with switching electric fields, pneumatic mixers etc. The weirdest was definitely using flagellar movement of a bacterium.

 

So integrating mixing into MF devices is a quite a big field under investigation with quite some more or less novel approaches.