Red-Gal® is chemically similar to X-Gal and can be used in the same in standard protocols for ß-galactosidase staining. Red-Gal® will develop a distinctive insoluble red precipitate as the result of ß-galactosidase activity as opposed to the dark blue stain produced by X-Gal. The chromogenic substrates, Red-Gluc® and Red-Phos®, can be used as direct replacements for X-Gluc and X-Phos, respectively, in standard staining applications.

Typically, most buffer solutions are prepared by dissolving the free acid form of the buffer compound at a known molar concentration and adjusting the pH with a solution of sodium hydroxide to the desired buffering pH. Once the desired pH is reached, the buffer solution is brought up to the final volume.

Alternatively, the same buffer solution can be prepared by using eqimolar portions of the free acid and sodium salt form of a buffer compound such as HEPES and HEPES, Na. The compounds are dissolved in water and, if necessary, adjusted to the desired pH with 1N HCl or 1 N NaOH, before diluting to the final volume.

A convienent way to prepare many of the biological buffers is to obtain the hemisodium salt form such as HEPES, hemisodium salt (HEPES, 0.5 Na) and dissolve the desired molar quantity in solution. Again, if necessary, adjusted to the desired pH with 1N HCl or 1 N NaOH, before diluting to the final volume. Many of the common biological buffer compounds, such as MES, TRIS and PIPES, are now commercially available as the hemisodium or sesquisodium salt forms.

It is possible to visually detect and differentiate multiple enzyme markers within the same sample using a combination of chromogenic enzyme substrates which form different colored stains.

An example of this approach would utilize marker enzymes for ß-galactosidase and alkaline phosphatase in a given biological sample. Using combination of Red-Gal® to detect ß-galactosidase, which generates a red insoluble stain, and X-Phos to detect alkaline phosphatase, which generates a blue insoluble stain, the enzymatic activity of each enzyme can be localized within the specimen.

Red-Phos® and Red-Gluc® are two other chromogenic enzyme substrates which generate a red insoluble stain as the result of alkaline phosphatase and ß-glucuronidase activity, respectively.

The traditional combination of fluorophores for dual fluorescent labeling applications are fluorescein and tetramethylrhodamine. These dyes are typically introduced as conjugates using FITC and TRITC resulting in fluorescently labeled products with corresponding emissions of 520 nm and 570 nm.

The same fluorescent labels can be introduced using carboxyfluorescein-N-hydroxysuccinimidyl ester and carboxytetramethylrhodamine-N-hydroxysuccinimidyl ester as the labeling reagents which form stable conjugates.

Cy3™ Reactive Dye has been shown to be suitable alternative for TRITC, which produces labels that are more intense and more water soluble. Cy5™ Reactive Dye has been recommended as a fluorescent label where a third distinct label is desired. The emission of Cy5™ is 677 nm and requires electronic detection in the near infrared.

Research Organics has a chart and instructions on how to use the indole butyric acid products. These instructions are shipped with the product documentation. Many of the plant growth hormones are soluble in water - most of the sodium and potassium salts. The free acids need to be solubilized in a minimal amount of alcohol, such as ethanol or methanol, and then complete the dilution with water. These stock solutions can remain stable at room temperature or in the refrigerator the entire growing season (up to 6 months).

Research Organics does not set expiration dates on its biochemicals. Based on stability studies and years of experience, we set up requalification requirements on our specifications. Please see individual specifications for requalification recommendations. We encourage the end user to set their own expiration based on their own application.

Research Organics sets requalification on our specifications sheet. Print or view our specification sheet on this site and obtain the requalification interval (normally 2 years). On the lot-specific Certificate of Analysis, see the TESTING DATE, add the requalification interval to the testing date, and that is Research Organics' recommended shelf life or expiration.

The Certificate of Analysis is a lot-specific specification versus testing analysis controlled document. All the testing required by Research Organics for approval and release is listed on this lot-specific Certificate of Analysis. If there are tests that you expect but do not see on this analysis, please call our technical services. Research Organics'  Quality Control tests each lot and issues a Certificate of Analysis, which ships with the product.

Protecting a product from temperature abuse is important to the overall quality of the product. We recommend long-term storage conditions on the lot-specific Certificate of Analysis, as well as our specifications. For the most part, we ship at room temperature and recommend that you store the product at the temperature listed on the Certificate of Analysis upon arrival. Those items that will degrade on a seasonal basis are shipped in dry ice or ice packs.

Research Organics Management Quality Systems is certified to ISO 9001:2000 international standard by Moody International. We embrace concepts and procedures of the FDA-regulated GMPs. We adhere to GMP and ICH systems that include: documentation practices, training, process control, change control, laboratory controls, validation, qualification, complaint and sample retention, rejection and reuse material control, packaging, preservation and storage. Please contact our technical services number or e-mail Quality Systems for more information.

Yes, we meet some of these requirements, but since we are not a drug manufacturer, we are not required to be regulated by the FDA. Our products are used in an excipient application upstream from the final drug product. We test using ACS, USP, EP and FCC protocols and give a lot-specific Certificate of Analysis to these specifications. We adhere to GMP and ICH systems that include: documentation practices, training, process control, change control, laboratory controls, validation, qualification, complaint and sample retention, rejection and reuse material control, packaging, preservation and storage. For more information, please contact Quality Systems.

If available, this is noted on our product specification sheet in the Notes Section. We can supply TSE and BSE-free certificates. Plant materials are tested for GMOs and we can supply GMO-free certificates. Please contact our technical services.

When choosing a buffer compound, it is recommended that the buffer mimics the desired pH based on the pKa. Research Organics lists the pKa and useful pH range for the biological buffers in its 2004-2006 catalog on pages 251-252. This buffer reference chart is also available from Research Organics as a wall poster for your lab or office. Research Organics supplies buffers to a varied customer base, such as drug makers, clinical reagent manufacturers and cell culture media producers. All have a critical need for high purity buffers that work with their specific application and not have any interfering impurities or contaminants. The extent to which a protein or solution may be stabilized or destabilized by a buffer depends on many factors; thereby making the selection of a buffer a formidable challenge. Buffers used in formulations should not serve as substrates or inhibitors. They should exhibit little or no change in pH with temperature, show insignificant penetration through biological membranes, and have maximum buffer capacity at a pH where the protein or formulation exhibits optimal stability. Choosing the best buffer for your application and the concentration that it will be most effective, the ionic strength of the buffer and the temperature that it will be used are all factors to consider when choosing a buffer.  Research references will lead you to one buffer or another. Research Organics has the book Buffer Solutions The Basics by R.J. Beynon and J.S. Easterby for free with a $200 or more dollar retail purchase. We also offer a line of tissue culture tested and microbiological tested products that ensure no objectionable organism in our products .

We are celebrating our 50th anniversary in 2004. Research Organics is a pioneer in the manufacture of zwitterionic biological buffers and established the current industry standards for many of these chemicals. We are a primary manufacture of biochemicals. These products have been used to pioneer development of some of the critical products and diagnostics kits used in today's health care system. We have a strong synthetic chemistry expertise and history supplying biochemicals to the research, diagnostic, pharmaceutical, biopharmaceutical and cell culture industries.

Yes, Research Organics does provide custom synthesis services for existing and novel compounds. We generally accept requests for products for chemicals that fit into our general synthesis capabilities such as buffer compounds, enzyme substrates, amino acid derivatives, fluorescent dyes and biochemical reagent compounds. We can also provide custom services for formulations and solution products. Requests for custom synthesis can be directed to our technical department for evaluation. We ask that you provide the chemical name, quantity, CAS number, desired specifications, test methods if available and any reference information that you may have related to the chemical properties or preparation of the desired compound. Our Research and Development chemists will work directly with technical representatives to identify critical specifications related to the customer application and develop compounds suitable for their needs.

Research Organics offers a variety of fluorescent compounds for staining, labeling and enzymatic assays. Our 2004-2006 catalog lists a separate section of our fluorescent compounds on pages 297-324 which includes a list of general reference articles for various fluorescent derivatives. For labeling applications, the customers need to identify compounds that are reactive function group such as Isothiocyanate (ITC) compounds for conjugation to primary amine groups. Our technical service can provide general protocols and technical assistance on the preparation of fluorescent conjugates. The customer also needs to identify the desired absorption/emission wavelength for visual and detection of the fluorescent compound. They need to consider the instrumentation detection system or optical device for their application. Our catalog lists emission maxima and extinction coefficients for individual compounds and we can provide a technical data sheet listing this useful information by request.