Figure 4
From: Make Caffeine Visible: a Fluorescent Caffeine “Traffic Light” Detector
The comparison of caffeine concentration acquired from HPLC and fluorescence methods.
Y-axis indicates the caffeine concentration and X-axis indicates different types of drinks. Grey bars indicate caffeine concentration derived from HPLC and colourful bars indicate caffeine concentration derived fluorescence, both after extraction processing. The bar below is correlating with the colour that different concentrations of caffeine in the drinks could expose. Values are represented as means and error bars as standard deviations (n = 3).
