6-Carboxyfluorescein dipivalate | CAS 192374-17-7

6-Carboxyfluorescein dipivalate is a cell-permeant fluorescein derivative designed for fluorescent labeling workflows where ester masking is used to improve loading into biological samples prior to intracellular or assay-driven deprotection. Upon conversion to the corresponding carboxyfluorescein species, the dye provides strong green fluorescence that is widely used for tracking, uptake studies, and labeling of biomolecules or cells in fluorescence-based assays. Its fluorescein core also supports common fluorescence readouts on standard microscopy and plate readers, making it a practical reagent for molecular imaging and quantitative fluorescence experiments.

1. Live-Cell Uptake Imaging

6-Carboxyfluorescein dipivalate is frequently used by cell biology and imaging laboratories to visualize dye uptake and intracellular distribution following membrane entry. Researchers load cells with the dipivalate ester, then monitor the resulting fluorescein fluorescence to assess relative internalization, washout kinetics, and compartmental retention using fluorescence microscopy. The carboxyfluorescein signal provides a convenient readout for comparing labeling across experimental conditions such as transport perturbations, incubation time courses, or differences in cell handling protocols.

2. Fluorescent Labeling Standards

6-Carboxyfluorescein dipivalate is also used to generate consistent fluorescein-based fluorescence standards and calibration materials for instrument setup and method development. Because the dye is commonly converted to a fluorescein carboxylate form under labeling conditions, many workflows employ it to verify excitation/emission alignment on fluorescence microscopes and plate readers, and to support routine performance checks for green-channel imaging. Laboratories using quantitative fluorescence assays often rely on fluorescein reference signals from this reagent-derived dye to standardize measurement settings across experiments.

3. Flow Cytometry Dye Loading

6-Carboxyfluorescein dipivalate supports flow cytometry workflows where intracellular fluorescence is used as a quantitative proxy for dye uptake and labeling uniformity across cell populations. After loading, the fluorescein fluorescence enables gating strategies to compare fluorescence intensity distributions between treated and control samples, including time-dependent labeling studies and batch-to-batch consistency checks. This makes the reagent useful for researchers performing high-throughput cellular fluorescence readouts where a robust green fluorophore signal is required.

4. Fluorescence-Based Uptake Assays

6-Carboxyfluorescein dipivalate is applied in fluorescence assay development to quantify uptake or intracellular accumulation in multiwell formats. Assay developers use the reagent to generate a measurable green fluorescence signal after conversion to the fluorescein form, enabling kinetic measurements and endpoint comparisons in plate reader experiments. Such workflows are common in chemical biology and biomaterials research where uptake behavior of cells under different incubation conditions needs to be monitored reproducibly using standardized fluorescence instrumentation.