A High Spatiotemporal Iontronic Single-Cell Viscometer
(a) The electroosmotic effect (20 min) induced the presence of fluorescein within the lumen. . (b) SPV caused no appearance of the fluorescence. (c) Ionic responses in glycerin-HEPES milieus with different viscosities under -1.0 V. (d) The corresponding derived linearity of log viscosity (cP) vs. ionic signals (nA). (e) The ionic effects of (i) 2.5 mM, (ii) 10 mM, and (iii) 15 mM Na+. (f) The pH values of 6.6, 7.4, and 7.8 in HEPES milieu of 60 cP. (g) Three adsorption tests were sequentially performed after immersing the nanotool in the cell lysate for 10 min.