Can microfluidic chips be used for plasma exosome isolation?

Recovery and purity vary greatly depending on the chip principle, so you cannot directly apply numbers from the literature. I suggest you perform your own methodological comparison: split the same sample into three aliquots and process them by ultracentrifugation, precipitation, and chip-based methods, then use NTA to measure particle size and concentration, BCA to measure protein, and Western blot to assess CD63/CD81 markers. Focus on the removal rate of contaminating proteins, because albumin and lipoproteins in plasma are easily co-enriched. Chip-based methods usually have an advantage in purity, but recovery may be lower than ultracentrifugation. Regarding clogging, pretreatment filtration is key, and an inline pre-filtration module can be added. If the manufacturer says it will not clog, do not fully believe it; ask clearly about the maximum particle tolerance and the cost of filter replacement.

If the finished product does not match, the customization lead time is indeed relatively long. Generally, after the drawing is confirmed, prototyping takes 2-4 weeks. For small quantities, the unit price will be higher. Within 5,000, making 20 pieces or fewer may be possible, but including design fees and mold fees, it is basically not enough. In your case, it is recommended to first confirm the plasma loading volume, target particle size, and chip channel dimensions before deciding whether to buy a finished product or customize one. When customizing, be sure to use standard Luer or 1/16-inch connectors for the ports to facilitate connection to a syringe pump. In addition, ask clearly about the effect of the material on EV adsorption. PDMS adsorbs proteins and lipids, while COC or glass may be better. If you are worried about pore clogging, you can ask the manufacturer to add a filter at the inlet or design a replaceable filter membrane structure; otherwise, if it clogs, the entire chip will be scrapped.

There are ready-made microfluidic chips that can be connected to a syringe pump for exosome isolation. The common ones are based on size exclusion/nanofiltration membranes or inertial focusing principles. A plasma volume of 1-2 mL is manageable for a syringe pump. However, plasma cannot be loaded directly. It is best to first centrifuge at 3000 g for 10 min to remove platelets and large cell debris, then filter through a 0.8 μm filter; otherwise, the pores will clog easily. With a budget within 5000, if you are only buying consumable chips, there are still options; if it includes the pump, tubing, and a ready-made kit, it may not be enough. You can first contact several domestic manufacturers making EV isolation chips to apply for trial samples and check the throughput and clogging situation. The key is to ask clearly whether the chip pore size or molecular weight cutoff is targeted at the 50-150 nm range, and whether it can tolerate the viscosity of plasma.