Stem cell & organoid research
Directed differentiation is a schedule of growth factor pulses, not a single reagent. Maintaining pluripotency, then pushing a line down a lineage, means swapping defined combinations of TGF-beta-superfamily ligands, BMPs, Wnt agonists, and morphogens on a defined timeline, with lot-to-lot bioactivity consistency that matters more here than almost anywhere else in the catalog.
Maintain pluripotency
hPSC maintenance media are typically built around FGF2 and TGF-beta/Activin A signaling to hold cells in a self-renewing state, check the datasheet's bioactivity assay and ED50, not just purity, when qualifying a new lot.
Direct differentiation
Sequential pulses of BMPs, Wnt agonists (R-spondin-1), and antagonists (Noggin) push cells toward germ-layer-specific fates on a defined protocol timeline, the same ligand can push opposite directions depending on when and how long it's applied.
Support 3D culture
Organoid and embryoid-body culture generally moves to a defined, serum-free specialty medium once differentiation starts, to avoid the batch variability serum introduces into a multi-week protocol.
Passage without shearing
Organoids and embryoid bodies are shear-sensitive, a gentle, recombinant dissociation reagent preserves structure and viability far better than trypsin for passaging 3D structures.
Recombinant Human Activin A
Recombinant Human TGF-β1
Every product below is pulled live from the catalog, not hand-curated marketing copy.
Carrier-free or BSA-carrier growth factor?
Both formats are stocked on every factor. The BSA-carrier version (0.1% BSA in the same PBS) stabilizes the protein through freeze-thaw and dilution and improves recovery at low nanogram concentrations, but the BSA is an undefined protein background you may not want in a fully defined or GMP-track medium. Carrier-free is the right default for stem cell work where medium composition needs to stay fully defined; pair it with low-retention plasticware.
Why does endotoxin level matter here specifically?
Endotoxin activates TLR4 signaling and can drive spurious differentiation or apoptosis in sensitive stem cell cultures at levels that are a non-issue for a robust immortalized line. Hold growth factors used in stem cell protocols to the low-endotoxin release limit on the datasheet (typically <0.1–1 EU/µg) and don't mix lots mid-protocol.
How should I aliquot and store a growth factor?
Factors arrive frozen in PBS. There is no reconstitution step. Thaw on ice, single-use aliquot immediately into low-protein-binding tubes, and return them to -80 °C; avoid repeat freeze-thaw, since most recombinant cytokines lose measurable bioactivity after 3–5 cycles even when the protein looks intact by SDS-PAGE.
Do I need to re-qualify a new lot before switching?
Yes, for any protocol where timing and dose matter, run a small-scale qualification (a differentiation marker readout, not just a proliferation assay) against your old lot before switching a long protocol over, even when the CoA's ED50 falls within the same nominal range.
More application workflows, curated products, and category links live on the applications hub. Datasheets, SDS, and Certificates of Analysis are under Documents.