Figure 1.
(a) Scheme summarized the preparation of BM-targeting PEG-PLGA NPs and non-targeting PEG-PLGA NPs via nanoprecipitation method. The collagen IV-targeting peptide (Col(IV)-TP) was conjugated to maleimide-functionalized PEG(5K)-PLGA(10K) prior to the prior to the preparation of BM-targeting NPs. (b) TEM images recorded for (i) BM-targeting and (ii) non-targeting NPs. (c) Number-average particle distribution curves recorded for 5 μg/mL of (i) BM-targeting NP and (ii) non-targeting NP dispersions, as determined by NTA method. It was determined that both NP dispersions contain about 4.5 × 109 particles per mL(d) Mean zeta potentials (ζ) of BM-targeting and non-targeting NPs dispersed in 1 mM NaCl electrolyte and 0.1 M PBS. (e) UV-visible absorption and fluorescence spectra recorded for BM-targeting NPs and non-targeting NPs. (f) In vitro fluorescence image recorded for (i) 0.150, (ii) 0.375, (iii) 0.750, (iv) 1.125, and (v) 1.500 nM of BM-targeting NPs. (N.B. * denotes p < 0.05, i.e. statistical significance.)