Synthesis and physico-chemical characterization of NanoK: (a) Schematic describing the preparation of bismuth-enriched K-edge nanocolloid (NanoK)): (i) Suspension of bismuth neodecanoate (1) in sorbitan sesquioleate, vigorously vortex and mixing, filter using cotton bed, vortex; (ii) preparation of phospholipid thin film (iii) resuspension of the thin film in water (0.2 µM); (iv) microfluidization at 4°C, 12,000 psi, 4 min, dialysis (cellulosic membrane, MWCO 20K).; (b)hydrodynamic particle size distribution from DLS; (c) characterization table for three replicates of NanoK; (d) anhydrous state TEM images (staining: uranyl acetate; scale bar: 100nm; (e) AFM image