Taking CE in Hand
More miniaturization of analytical tech with a hand-held capillary electrophoresis device
What?
A device combining capillary electrophoresis (CE) with laser-induced fluorescence detection, small enough to fit in the palm of your hand (90 x 75 x 77mm). Made from off-the-shelf components, the mini-bioanalyzer costs $500 to produce, but – say the team – still has sensitivity that is comparable with larger instruments (1).
Figure 1. Fully-integrated palmtop CE bioanalyzer. (a) Overall appearance. (b) Uncovered appearance. (c) Electropherogram of separation of amino acids. (d) Electronic module of the bioanalyzer. Reproduced from (1).
Figure 2. (a) Instrument structure; (b1–b3) LIF module: (b1) Optical components, capillary and holder; (b2) Assembled LIF module; (b3) Assembled LIF module integrated with a capillary and slotted vial array. (c) Linear relationship of fluorescence intensity to concentration in the test of LoD for sodium fluorescein. (d) Typical recording of LIF intensity signals of 5 nM sodium fluorescein in the test of LoD. Reproduced from (1).
Why?
Not only is the device likely to be easier and quicker to produce in quantity, but its portability could also lend itself to point-of-use or companion diagnostic applications. The palmtop CE has already been applied to the diagnosis of colorectal cancer, where it was able to distinguish any mutation and mutation status of the KRAS gene (1).
How?
A short glass capillary (4 cm) with a tapered end allows extraction of a single droplet from the sample. The CE separation is coupled to a laser-induced fluorescence detector, also developed by the team. The device is completed with a commercially available mini microcontroller, a battery, and an LCD screen (see image).
Who?
The project is a collaboration between scientists from the Department of Chemistry and Innovation Center for Cell Signaling Network, Zhejiang University and the Department of Cell Biology, China Medical University, China.
What next?
The team are certainly planning on commercializing the current device, but are already using similar low cost components in an attempt to miniaturize other devices; for example, for immune and biochemical assays.
- Jian-Zhang Pan et al., “A low-cost palmtop high-speed capillary electrophoresis bioanalyzer with laser-induced fluorescence detection”, Sci Rep, 8, 1791 (2018).
A former library manager and storyteller, I have wanted to write for magazines since I was six years old, when I used to make my own out of foolscap paper and sellotape and distribute them to my family. Since getting my MSc in Publishing, I’ve worked as a freelance writer and content creator for both digital and print, writing on subjects such as fashion, food, tourism, photography – and the history of Roman toilets. Now I can be found working on The Analytical Scientist, finding the ‘human angle’ to cutting-edge science stories.
