InterLab

Introduction

As a bronze medal requirement, iGEM teams have to partake in the InterLab study. These experiments carried out by laboratories across the world ensure that their studies are reliable and repeatable, a key component of scientific disciplines.

Fluorescence is a property commonly measured in synthetic biology however data from different studies often cannot be compared because different units have been used, the data has been processed differently and results are given in ‘relative expression’. The InterLab study aims to address this by using a detailed protocol and data analysis to yield absolute units for measuring GFP, this year focussing on how close the numbers can be when fluorescence is measured all around the world.

Experiments

Note: Due to being a high school team we did not own a plate reader so our InterLab study was carried out at the University of Kent in conjunction with their iGEM team’s InterLab study.

Firstly we had to transform the 8 plasmids (positive control, negative control, 6 test devices) into E. coli DH5-alpha cells. This took several attempts using the parts on both Kit Plate 6 and 7.

OD600 Reference Point: This was carried out in order calculate a conversion ratio from our absorbance data (measured by LUDOX-S40) to a standard OD600 (optical density) measurement.

Plate reader Settings:

Wavelength: 600nm

Path Length Correction: Off

Fluorescein Fluorescence Standard Curve: This was done to measure the fluorescence of varying fluorescein concentrations produced from a serial dilution. A standard curve was then produced so that cell based fluorescence readings could be converted to a fluorescein concentration and therefore a GFP concentration.