Spheroid growth monitoring tracks the size, morphology, and viability of 3D cell aggregates over time using brightfield live cell imaging inside the CO₂ incubator. zenCELL owl images spheroids in all 24 wells continuously without disruption, measuring spheroid diameter and area at every timepoint automatically.

What is a spheroid and why is it used?

A spheroid is a three-dimensional cell aggregate formed when cells are cultured under non-adherent conditions — ultra-low attachment plates, hanging drop, or spinner flask. Spheroids better recapitulate in vivo tumour architecture than 2D monolayer cultures: they develop oxygen, nutrient, and drug penetration gradients that influence cell behaviour, drug sensitivity, and gene expression. They are widely used in oncology drug screening, toxicology, and tissue engineering.

How does zenCELL owl monitor spheroid growth?

zenCELL owl captures brightfield time-lapse images of spheroids in multiwell plates inside the CO₂ incubator. Its software automatically measures spheroid cross-sectional area (µm²) and diameter (µm) at each timepoint, generating a growth curve per well. No manual measurement in ImageJ required. The plate never leaves the incubator — no disruption to spheroid culture conditions.

What spheroid formats are compatible?

• Ultra-low attachment 24-well and 96-well plates (single spheroid per well)
• Hanging drop plates
• Standard well plates with methylcellulose or Matrigel overlay
• Any format where spheroid is visible in brightfield from below

Can zenCELL owl image spheroid interiors or perform Z-stacking?

No. zenCELL owl is a brightfield widefield imager — it images the spheroid footprint and profile from below. It does not perform optical sectioning, Z-stacking, or confocal imaging of spheroid interiors. For internal spheroid structure (necrotic core, proliferating rim, invasion fronts), confocal or light sheet microscopy is required.

What has been published on spheroid imaging with zenCELL owl?

Ferreira et al. (2023), Toxins — monitored Caco-2 intestinal spheroid growth and mycotoxin cytotoxicity over 48 hours using zenCELL owl continuous brightfield imaging inside the incubator.

Can zenCELL owl measure spheroid drug response?

Yes. After drug treatment, zenCELL owl tracks spheroid size change over time. Drug response appears as growth inhibition (flattened size curve) or spheroid shrinkage (decreasing area). Combined with brightfield morphology — compact vs. loose aggregate, dark necrotic core — this gives a multi-parameter readout of drug effect without staining.

Book a free demo → See spheroid growth monitoring live across 24 wells.