C phycocyanin from spirulina sp

Spectrophotometric UV-Vis analyses were performed with a Cary Bio spectrophotometer equipped with a 96-well plate reader (Varian) using a 200 μl sample at 22°C. Fluorescence measurements were performed with a Cary Eclipse Fluorescence Spectrophotometer equipped with a multiwall-plate reader (Varian) in black 96-well plates with a 200 μl sample and with λ_ex = 609 nm and λ_em = 400–700 nm. Total protein concentration of cell extracts was estimated by measuring the absorbance at 280 nm, and CPC concentration was determined from the absorbance at 620 nm using an extinction coefficient ε^1%₆₂₀ = 70. As reference, the commercial C-phycocyanin from Spirulina sp. (Arthrospira sp.) was purchased from Sigma Aldrich (product nr. P2172, Switzerland).

C-phycocyanin (from Spirulina sp.) was purchased from Sigma-Aldrich (Shanghai, China) with a purity of 99% determined by HPLC. Albumin from Bovine Serum (BSA) with a purity of 96% and ThT (thioflavine T) were purchased from Aladdin Bio-Chem Technology (Shanghai, China). All other chemicals used were of analytical reagent grade.