(b) Table Q1 below provides optical measurements of samples with known concentrations of analyte (ten samples were measured and the average and standard deviation are presented). They are also represented graphically in Figure Q1, below the table. Analyte concentration (nM) 0.1 Standard deviation 0.2 0.5 Table Q1 Fluorescence intensity (average) 9300 9200 10800 19600 37200 90000 178000 224000 1 2 2000 1200 1000 2000 10000 30000 25000 40000 5 10 15 300000 250000 200000 fluorescence intensity 150000 100000 50000 0 0 5 10 15 [Analyte]M Figure Q1. Signal intensity for different analyte concentrations. Error bars are standard deviation. (1) Describe what is meant by biological replicates [2] (ii) Calculate the limit of detection (LOD) for this sensor. [6] (iii) A patient sample measured using this biosensor in the diagnostic laboratory generates a signal of 142800. The coefficient of variation of the device is 5%. Explain whether the diagnostic lab would have the confidence to report that the sample has a concentration in analyte of 8 nM or whether it should only report it as positive. [6]