Synthesis and physico-chemical characterization of self-assembled Ytterbium nanocolloids (YbNC). Schematic describing the preparation of Yb-enriched YbNC: (i) Suspension of Yb(III)-2,4-pentanedionate in Polyoxyethylene (20) sorbitan monooleate, vigorously vortex and mixing, filter using cotton bed, vortex; (ii) preparation of phospholipids thin film comprised of egg lecithin PC, (iii) resuspension of the thin film in water (0.2 µM); (iv) microfluidization at 4°C, 20,000 psi (141 MPa), 4 min, dialysis (cellulosic membrane, MWCO 20K).; characterization table for a representative preparation of YbNC.; (a) Number-averaged hydrodynamic diameter distribution of YbNC; (b) TEM images of the lipid-encapsulated nanocolloids; (c) AFM image of YbNC drop deposited over glass grid; (d) Physico-chemical characterization chart.