Fig. 2

Stain assessment slide H&E stain response. a) Mean absorbance spectra of biopolymer film on stain assessment slides, stained with H&E (equal time each stain) from 1 to 6 min, with five slides stained at each stain duration. The reference lines provided indicate the portion of the spectrum that represents visible light wavelengths, between 380 and 740 nm, from which total absorbance was measured. b Average total absorbance of biopolymer film stained using haematoxylin, eosin and H&E combined, for durations ranging from 15 s to 6 min. Each point plotted is the average of five slides at each stain duration, with error bars depicting one standard deviation from the mean in each direction and linear trend lines applied