Fig. 4 PPM-DD–optimized ND-drug combinations. PPM-DD–optimized ND-drug combinations. (A) A schematic model of the PPM experimental framework. Dox, doxorubicin; Bleo, bleomycin; Mtx, mitoxantrone; Pac, paclitaxel. (B) PPM-derived optimal ND-drug combinations (NDC) outperform a random sampling of NDCs in effective therapeutic windows of treatment of cancer cells compared to control cells. Reprinted (adapted) with permission from H. Wang et al., Mechanism-independent optimization of combinatorial nanodiamond and unmodified drug delivery using a phenotypically driven platform technology. ACS Nano (2015/02/17, 2015). Copyright 2014 American Chemical Society. Dean Ho et al. Sci Adv 2015;1:e1500439 Copyright © 2015, The Authors