Refractive Index Sensing for Measuring Single Cell Growth

Accessing cell growth on adhesive substrates is critical for identifying biophysical properties of cells and their therapeutic response to drug therapies. However, optical techniques have low sensitivity, reliability varies with type, whereas microfluidic technologies rely suspension. In this paper, we introduced a plasmonic functional assay platform that can precisely measure weight the dynamic change in real-time adherent cells. Possessing ability, our determine rates individual within only 10 min map profile populations short time intervals. The could successfully heterogeneity assess subpopulations exhibiting distinct profiles. As proof principle, investigated MCF-7 effect two intracellular metabolisms proliferation. We first negative serum starvation growth. then studied ornithine decarboxylase (ODC) activity, key enzyme which involved proliferation, degraded under osmolarity inhibits determined significant distinction between profiles ODC-overproducing variants possess strong resistance effects osmolarity. also demonstrated an exogenous parameter, putrescine, rescue from ODC inhibition hypoosmotic conditions. addition ability accessing activities through ex vivo measurements, behaviors cancer treatments. Here, difluoromethylornithine (DFMO), has antitumor by inhibiting activity. susceptibility such treatment, while its DFMO-resistant subpopulation survive presence antigrowth agent. By rapidly determining kinetics small samples, may be broad use basic research clinical applications.