Doxycycline (Hyclate), 10 g

A water-soluble tetracycline-class antibiotic, doxycycline hyclate from STEMCELL Technologies is supplied as a 10 g bottle of yellow crystalline powder for research use. In molecular and cell biology laboratories, it is best known as the effector molecule for tetracycline-controlled transcriptional activation systems, including Tet-On and Tet-Off constructs, where it binds the reverse tetracycline-controlled transactivator (rtTA) or tTA to switch transgene expression on or off in engineered mammalian cells, stem cells, and model organisms.

Working concentrations typically range from 10 ng/mL to 1 µg/mL for inducible expression, while 1-10 µg/mL is commonly used to suppress bacterial contamination in routine culture of transfected or contaminated cell lines. The hyclate salt offers improved aqueous solubility over the free base, so 10 mg/mL stock solutions can be prepared directly in cell culture-grade water before sterile filtration, and stocks in DMSO remain stable for long-term freezer storage. Recommended handling includes protect from light, store the dry reagent at room temperature in a tightly sealed container, and avoid repeated freeze-thaw cycles of aliquoted working stocks. Each lot supports reproducible performance in cell culture, reporter gene assays, and conditional knockout experiments.