Pure, crystalline urea (CH4N2O), CAS 57-13-6; denaturant with low UV-absorptivity for protein biology methods (elution, solubilization, refolding, storage).

Immobilize or conjugate proteins using 1-Ethyl-3-(3-dimethylaminopropyl) carbodiimide (CAS 25952-53-8), a water-soluble, carboxyl-to-amine crosslinker.

DTT, 1M

Ready-to-use solution for the exclusion of nonviable cells in flow cytometric analysis. Can be used in combination with PE- and FITC-conjugated antibodies in 2-color analysis. The advantage of 7-AAD over PI is that there is minimal spectral overlap between these emissions.

Combines exceptional photostability with bright and intense signals. Cytiva Cy3B NHS Ester Mono-Reactive CyDye provides targeted and specific labeling of amine residues on antibodies, peptides, or oligonucleotides in fluorescence polarization applications.

Ready-to-use, 8M solution of guanidinium hydrochloride (GdnCl, GuHCl), CAS 50-01-1; dilute and pH-adjust to any concentration for protein biology methods.

Short (2.8A), amine-reactive (NHS ester) sulfhydryl-addition reagent; creates stable (protected yet exposable) -SH group for protein crosslinking strategies.

Reduce protein and peptide disulfide bonds using this thiol-free, pure, crystalline tris (2-carboxyethyl) phosphine hydrochloride, TCEP (CAS 5961-85-3).

Efficiently reduce protein disulfide bonds with this stable, odorless, 0.5M solution of TCEP reducing agent that is ideal for making reducing SDS-PAGE sample buffers.

Alexa Fluor™ 488 Protein Labeling Kit

Crosslink amines to amines with BS3; composed of sulfo-NHS-ester groups separated by an 11.4A, water-soluble spacer arm that is useful for cell-surface protein crosslinking.

Prepare amine-reactive sulfo-NHS-ester crosslinkers or enhance carbodiimide (EDC) conjugation for peptides or proteins using N-hydroxysulfosuccinimide, CAS 106627-54-7.

Alexa Fluor™ 647 NHS Ester (Succinimidyl Ester)

Crosslink amines to sulfhydryls with this mid-length, water-soluble crosslinker made of NHS-ester and maleimide groups at ends of a cyclohexane-containing, 8-atom spacer arm.

Pegylate amines (-NH2 groups) on proteins (lysine residues) or assay surfaces using MS(PEG)n, amine-reactive (NHS ester), methyl-capped PEG compounds (4 to 24 EG units).

Use for highly accurate labeling of amine groups. Cytiva Cy5.5 NHS Ester Mono-Reactive CyDye contain derivitized CyDyes that carry only one reactive group on each dye molecule for accurate labeling of amine groups, for example on antibodies, peptides, or oligonucleotides.

Alexa Fluor™ 647 azide, triethylammonium salt

Reduce disulfides in biological buffers and sample loading buffers with pure, crystalline dithiothreitol (DTT), the most popular protein disulfide reducing agent.

Generate and purify Fab fragments from antibodies with cysteine-endopeptidase papain immobilized onto beaded agarose resin.

Activated derivatives of green-fluorescent fluorescein dye to label antibodies, proteins and other molecules for fluorescence imaging (ex 494; em 518).

Use for highly accurate labeling of amine groups. Cytiva Amersham™ CyDye™ Value Packs (mono-Reactive NHS Ester) contain derivitized CyDyes that carry only one reactive group on each dye molecule for accurate labeling of amine groups, for example on antibodies, peptides, or oligonucleotides.

Pure, liquid (equals 14M), beta-mercaptoethanol (bME, 2BME, 2-ME, b-mer), CAS 60-24-2; thiol reducing agent for cleaving protein disulfide bonds (cystines cysteines).

monochlorobimane (mBCI)

Efficiently reduce protein or peptide disulfide bonds with this stable, odorless, beaded agarose resin on which Tris (2-carboxyethyl) phosphine is immobilized.

Crosslink amines to amines with disuccinimidyl suberate composed of NHS-ester groups with a membrane-permeable, mid-length spacer for intracellular protein crosslinking.

Crosslink sulfhydryls to sulfhydryls (cysteine residues in proteins or peptides) with this short crosslinker composed of maleimide groups and a 7-atom (8.0A) spacer arm.

Amine-reactive (NHS ester) compound to permanently block primary amines (e.g., protein lysine side chains) to prevent interactions or later conjugation.

Alexa Fluor™ 647 C₂ Maleimide

HABA dye reagent and biotinylated protein standard for convenient colorimetric determination of biotinylation levels in antibodies and other proteins.