Fig. 4
From: Engineering nano-drug biointerface to overcome biological barriers toward precision drug delivery
Reproduced with permission from Ref. [85] Copyright 2020, John Wiley and Sons
PEG surface modification enhances the ability of BPQDs to penetrate the sputum layer. A Visual inspection of how various samples penetrate through the artificial mucus layers. B Absorbance (at 595Â nm) detection at the bottom layer agarose gel of sputum layer penetration by diverse nanoparticles two h after administration. CS chitosan, AM amikacin, BPQDs black phosphorus quantum dots.