Fig. 3: Chemotactic motion of Trojanbots and the release of CatNbots.
From: A self-directed Trojanbot-enzymatic nanobot in neutrobot for active target therapy of glioblastoma
a Schematic illustration of the chemotactic motion of Trojanbots and the release of CatNbots under PMA stimulation, and the catalytic propulsion of CatNbots. b Time-lapse images of the chemotactic motion of Trojanbots along a chemokine gradient. c Trajectories (n = 7) and d direction distribution (n = 7) of Trojanbots in response to a fMLP gradient (10 pM µm−1). The duration of chemotactic motion is 10 min. e Dependence of chemotaxis velocity of neutrophils and Trojanbots on the chemokine gradient of fMLP (n = 3). f Dependence of CI (ratio of distance to path length) of Trojanbots on the chemokine gradient of fMLP (n = 6). The center line of the box plots represents the median, the box bounds indicate the 25th and 75th percentiles and the whiskers extend to the minimum and maximum values within the 1.5× interquartile range (IQR). Individual data points are overlaid. No outliers are present. g TAD of Trojanbots under chemokine gradient (n = 600). h TAD at 0° of Trojanbots under different gradients of fMLP (n = 6). The center line of the box plots represents the median, the box bounds indicate the 25th and 75th percentiles and the whiskers extend to the minimum and maximum values within 1.5× IQR. Individual data points are overlaid. No outliers are present. i Time-lapse images of CatNbots releasing process under PMA stimulation. The resting Trojanbots (i) were activated by PMA stimulation (ii), and the as-released CatNbots (iii) exhibited self-propelled motion in H2O2 solution (iv). j The effect of different concentrations of PMA on the release rate of Trojanbots (n = 3). k Dependence of Trojanbot release percentage on time with or without PMA (100 nM) stimulation. (n = 3). l CLSM images of CatNbots released from Trojanbots with (i) and without 100 nM PMA (h) after 8 h of in vitro culturing. The CatNbots were loaded with Cou6 (green), and the released DNA segments were stained with PI (red). m Representative tracking trajectories of the CatNbots (n = 20) in H2O2 solutions with different concentrations (0, 2, 4, 6, 8 µM) within 1 s. n MSD analysis (Δt = 1 s, n = 20) of CatNbots at different H2O2 concentrations (0, 2, 4, 6, and 8 µM). o The effective diffusion coefficient (Deff) (left) and self-propelled velocity of CatNbots (right) at different H2O2 concentrations (0, 2, 4, 6, and 8 µM) based on MSD. (n = 20). p The instantaneous velocity of CatNbots at different H2O2 concentrations (0, 2, 4, 6, and 8 µM) (n = 20). Data are presented as mean ± SD of three independent experiments (e, j, k), six independent experiments (f, g, h), seven independent experiments (c, d), and 20 independent experiments (o, p). Source data are provided as a Source Data file.
