The supernatant liquid was collected after centrifugation (10 min, 7500 rpm) and used for steady-state emission and fs-transient absorption spectroscopy. Steady-state emission spectra (λex = 380 nm) were recorded with a FLS980 spectrometer (Edinburgh Instruments) in a 1 cm quartz cell. Time resolved emission data were recorded using a Hamamatsu HPDTA streak camera. A Ti:sapphire laser (Tsunami, Newport Spectra-Physics GmbH) was used as the light source and a pulse selector (model 3980, Newport Spectra-Physics GmbH) was used to reduce the repetition rate of the fundamental to 400 kHz. The emission was collected from a 1 cm cuvette in a 90° angle between the pump beam and a CHROMEX spectrograph detector. Analysis of the time-resolved emission data was performed using DecayFit software.