Team:CLS CLSG UK/Hardware

Hardware

Hardware introduction

During our initial research stages, we realised that although cocaine is a large issue for aquatic ecosystems, perhaps a larger reason behind its inappropriate management was the difficulty of quantifying drug concentrations in water sources. The current methods involve taking samples and using extremely expensive analysis tools such as mass and infrared spectrometry to analyse concentrations[1][2] . Perhaps more importantly, taking regular samples in potentially toxic environments (such as the sewers) is time consuming and expensive in itself. We also found that many iGEM biology projects involved filtration and purification of water sources, but very few had accurate mechanisms of quantifying the effectiveness of their circuits. As a result, we planned on designing a comparatively cheap and automated solution to this problem, so that governments, environmental organisations and future iGEM teams could easily access large amounts of data showing the changes in their environments.

In order to find the most effective method for such a device, we looked at a variety of different analysis tools and compared them.

Analysis tool LoD (limit of detection) Cost (£) Practicality outside of lab
Mass spectrometry[1] 0.8-25ng/L 120,000 Samples to be taken from site. Residues to be formed via lab treatment. Large, heavy equipment. I.e. Not practical outside of lab
Infrared spectroscopy[2] 7.97pg/L 100,000 Requires much treatment within labaratory. Equipment is heavy and difficult to transport. I.e. Very impractical outside of lab
ELISA plate analysis[3] 20ng/L (vancomycin ELISA) 8000 Requires sampling at site. Lab treatment required to prepare ELISA plates. Samples need to undergo lab treatment to remove impurities.
Aptasensors as low as 10pM/L <2000 Electrodes require treatment in lab. Easily portable. Samples do not require much treatment. I.e. Practical outside of lab

In the end, we decided to use aptasensors because they are extremely useful for fast, sensitive and cost effective analysis of our target compound. It is so far the most sensitive electrochemical biosensor for the detection of many drugs, including antibiotics and cocaine. However, their function can be complicated so please see our design page for further details on its function.

References

  1. Mirzaei, R., Yunesian, M., Nasseri, S., Gholami, M., Jalilzadeh, E., Shoeibi, S., Bidshahi, H. S., & Mesdaghinia, A. (2017). An optimized SPE-LC-MS/MS method for antibiotics residue analysis in ground, surface and treated water samples by response surface methodology- central composite design. Journal of Environmental Health Science and Engineering, 15(1). https://doi.org/10.1186/s40201-017-0282-2 ‌
  2. Na, G., Gu, J., Ge, L. et al. Detection of 36 antibiotics in coastal waters using high performance liquid chromatography-tandem mass spectrometry. Chin. J. Ocean. Limnol. 29, 1093 (2011). https://doi.org/10.1007/s00343-011-0225-1
  3. Odekerken, J. C., Logister, D. M., Assabre, L., Arts, J. J., Walenkamp, G. H., & Welting, T. J. (2015). ELISA-based detection of gentamicin and vancomycin in protein-containing samples. SpringerPlus, 4, 614. https://doi.org/10.1186/s40064-015-1411-y