Confocal laser microscopy images of MPG lipid aggregates in extracts taken at various time points during lipid mediated β-haematin formation. Reaction times were 10 min (top left), 20 min (top right), 30 min (bottom left) and 60 min (bottom right). The dark non-fluorescent areas are unconverted Fe(III)PPIX, either precipitated, or lipid associated. Fluorescence profiles taken along cross-sections indicated by an arrow in each image are given below the images in red. The grey trace (ChD line) represents the transmitted light channel). Steady formation of β-haematin crystals is indicated by increasing fluorescence and is in qualitative agreement with kinetic traces, indicating about 60 min required to reach completion. Excitation was at 516 nm, emission in the range 575–630 nm. Reaction mediated by MPG, 0.54 L/H ratio, citric buffer (50 mM, pH 4.8), 37°C. Confocal microscopy was performed on wet samples. Acquisition conditions: λex = 561 nm; λem = 575–630 nm; pinhole diameter 444 μm; output power 20% transmission; scan zoom 1.0; objective LD C-Apochromat 40×/1.1 W. No z-stacking.