Capillary flocculation assays were performed using square glass capillaries of 0.4 mm inner diameter and walls of 0.2 mm (Vitro-Com, Mountain Lakes, NJ, USA). Homogenized α-synuclein amyloid seeds of 25 µM equivalent monomer concentration in 20 mM sodium phosphate buffer, 150 mM NaCl and 50 mM ThT, were mixed with 20 nM PK, loaded into a capillary and monitored for 18 hrs at 5 min intervals. The capillary was imaged using an inbuilt ThT channel in the Zeiss Axio vert. A1 microscope (Zeiss, Germany) with a 10X objective lens equipped with a CFP filter cube (model no. 424931, ex. 436/20, beam splitter 455, emission 480/40), illuminated using a Visitron Cool LED pE100 (Visitron Systems, Germany) operating at 440 nm. Flocculation is quantified from relative standard deviation of ThT intensity across the area of the inner capillary.