Gel Staining

Available dyes : SYPRO® Ruby , Siver stain and CoomassieT Blue.

Protein staining with SYPRO® Ruby

SYPRO Ruby protein gel stain is a luminescent metal chelate stain comprised of ruthenium as part of an organic complex.
SYPRO Ruby stain allows sensitive fluorescent detection of proteins. Gels are stained by simple incubation in a single solution. After staining, gels are de­stained and visualized using a standard UV light box, or any of a variety of laser-based gel scanners. The excitation wavelengths are 300 and 480 nm and the emission wavelength is 618 nm.

A comparison of the performance of SYPRO Ruby stain relative to other common stains utilized for protein detection demonstrates that the stain is equally or more sensitive than the best silver staining techniques. Quantification of stained proteins in polyacrylamide gels is difficult because colorimetric stains such as silver and Coomassie Blue have narrow linear dynamic ranges that only extend over an 8 - 15 fold range.

SYPRO Ruby stain has a dynamic range that exceeds that of silver and Coomassie stains by several orders of magnitude. SYPRO Ruby stains are fully compatible with Edman sequencing and mass spectrometry.

Silver staining kit

The Investigator Silver Stain Kit uses a modification of the Rabilloud procedure which has the
advantages of high sensitivity and high signal to noise. The procedure may be modified for nondestructive silver staining by omission of the glutaraldehyde in Fixative 2 Solution; this is useful when analysis by mass spectrometry is to be performed.

This procedure uses silver nitrate (as opposed to silver diammine) as the silvering agent and is a relatively quick method. Unlike silver diammine methods, this method is quantitative when the development time is kept to 10 minutes or less.

This allows spots to be quantified with densitometers or other scanning methods. For a review of silver staining methods, see the article by Rabilloud, T. in Electrophoresis, 13, 1992, 429-439.

Coomassie Blue

Proteins in SDS PAGE gels have traditionally been stained with Colloidal Coomassie brilliant blue stain. Colloidal Coomassie Blue is an easy and sensitive stain for SDS and native PAGE protein gels. Preparation is easy; just dilute the concentrate with methanol and you're ready to stain.