Team:Worldshaper-Shanghai/Demonstrate

Demonstrate

Our product called “Easy (blood) uric-acid monitoring kit”, we hoping it can provide gout patients with a efficient and fast way to monitor uric acid at their home.

This year, we completed the preliminary design of the project, and verified the relationship between the core components and the concentration of uric acid with experimental data and mathematical model. However, due to the limitation of time and the complex procedures of obtaining blood samples, we did not test the actual blood. We were continuing to improve the design of our portable testing kit through literature reviews, public surveys, expert interviews, field trips (such as the hospital), etc. We hope it will be more viable and accessible when we got the right opportunity to make it true.

Our easy (blood) uric-acid monitoring kit can be taken home by gout patients, and its volume will not be larger than a medium-sized handbag. Patients only need to take a small amount of blood and seperate serum by using a simple tools, then put the sample into portable device and get results.

All components in the kit are showed as following, we design two versions of it：

Components Test Paper Kit (Figure 1) Magnetic Beads Kit (Figure 3)
1 Capillary Blood Collecting Tubes
(It is the necessary tool to collect a small amount of peripheral blood (20 μL) from fingertip. )
2 Sterile bag
(Sterilizing during blood collection)
3 Paperfuge.
(Separating serum of above tubes via whirligigs.)
4 Test paper (cellulose acetate membrane)
(Sensing uric acid) 		magnetic beads
(Sensing uric acid)
5 Portable Device
(associating with cellulose acetate membrane) 		Portable Device
(associating with magnetic beads)
6 USB & charge
7 Mobile app
(for future analyze) 		-

Test Paper Kit Design

The Test Paper Kit will use positively charged cellulose acetate membrane as the material of the test paper.

Figure 1 Design of Test Paper Kit
Figure 1 Design of Test Paper Kit

The possible steps of the Test Paper Kit（Figure 2) :

  1. Extract patient's blood by using Capillary Blood Collection Tubes.
  2. Insert the tubes into the paperfuge , separating serum via whirligigs.
  3. Pipette serum into buffer solution and react with test paper, wobbling it on holder solftly for several minutes.
  4. A camera takes photos of the test paper under excitation source, the images is then sent to patient's mobile phone.
  5. The mobile app analyzes images and gives out result.
Figure 2 Possible operate steps of Test Paper Kit
Figure 2 Possible operate steps of Test Paper Kit

This is our early version of the portable testing Kit design. According to our results, there are some disadvantages in the way of fluorescence analysis by images, such as the low precision. Luckily we got a great idea from our team instructors who introduced the streptavidin magnetic beads to us, we shared this optional idea with other teams in meetups this summer and got some feedback from other iGEM teams and experts. The brief theory of spectrometer recommended by QHFZ-China iGEM team also helped us a lot. More details are presented on our Human Practice page.

Improved Design--Magnetic Beads Kit

The major instrument in Magnetic Beads Kit contains 1) capillary blood collecting tubes, 2) sterile bag, 3) paperfuge, 4) streptavidin-biotin magnetic beads, 5) magnetic separator, 6) portable device, and 7) USB and charger. The magnetic separator removes all streptavidin-biotin magnetic beads from solution, then the liquid will be recorded by portable device. This kind of portable device is a fluorescence detector, which inspired by QHFZ-China iGEM team and online sources[2-6].

Figure 3 Design of Magnetic Beads Kit
Figure 3 Design of Magnetic Beads Kit

In theory there is no red fluorescence in the solution under uric acid free condition. When uric acid is present, HucR-mCherry will leave pHucO so that the red fluorescence can be found in solution. Using a detection swab to collect a small amount of solution and insert it into the portable device, the number of uric acid will be showed on screen after detecting.

Figure 4 Possible operate steps of Magnetic Beads Kit
Figure 4 Possible operate steps of Magnetic Beads Kit

Unfortunately, this summer, we were not able to put these tentative plans into reality, but it is just the beginning. This experience is challenging but exciting to us, especially when the public show their interests and expectance to our device. If there is an opportunity, we hope to make it a reality.

Reference
  2. Asheim J，Kvittingen EV，Kvittingen L，et al. A Simple，Small-Scale Lego Colorimeter with a Light-Emitting Diode（LED Used as Detector［J］.Journal of Chemical Education，2014，91（7）：1037-1039
  3. FENG Qiting, PENG Baojin, CHEN Danlu，et al. The design and implementation of a simple spectroscopy instrument［J］.OPTICAL INSTRUMENTS,, 2013, v.35;No.330(2):80-84.
  4. Haga T, Sonehara T, Uchida K, et al. Fluorescence detector[J]. 2014.
  5. Sharififar A, Singh K, Jones E, et al. Evaluating a low‐cost portable NIR spectrometer for the prediction of soil organic and total carbon using different calibration models[J]. Soil Use and Management, 2019.
  6. （Online Source ）http://www.qdjchb.com/productshow-132-345-2196-1.html