The Ultimate Mucicarmine
Pushing the envelope of Speed, Performance, and Durability.
By: Ron Hightower, Quality Assurance Manager, AMTS, Inc.
Carmine is one of the oldest histological stains used to visualize mucins, beginning with Mayer in 1896 and followed by Southgate's method in 1927. More than three decades ago, American Histology Reagent Company (now American MasterTech) introduced the first commercially available Mucicarmine Stain. Over the years, American MasterTech has proven time and time again that with hard work and commitment, anything can be improved. Mucicarmine is no exception to that rule. Even though its initial staining formulations date back to well over a century, the staff at AMTS, Inc. has repeatedly made critical breakthroughs in performance since its initial release as the first commercially available Mucicarmine stain in 1982. Today, the company has once again outdone itself and is proud to announce a dramatic enhancement to the durability of this great stain.
Dactylopius coccus, commonly known as cochineal or coccus cacti, is a scale insect from which the crimson colored natural dye carmine is derived. The parasite lives on cacti of the genus Opuntia which is found throughout tropical and subtropical Mexico and South America. Carminic acid, the primary composition of carmine dye, is naturally produced by these insects to deter predators. Initially used in Central America during the 15th century to color fabrics, this dye now has a wide variety of uses as a coloring agent in foods, cosmetics, and histology. Text books usually state that mucicarmine demonstrates mucins, however, the stain is actually more selective, staining acidic mucins of epithelial origin and not that of gastric origin. In addition to these selective limitations, the staining procedure has traditionally taken a considerable amount of time to complete. The Mayer's and Southgate methods for Mucicarmine, once considered the gold standard for Mucin staining, can take up to two hours to complete.
During the 1980's, the company's research and development team first sought to improve the performance of the stain by making it rapid and more vibrant. Muci-10 Carmine Stain was the first of these developments and became available in June, 1983. With improved staining in just 10 minutes, Muci-10 took the industry by storm and quickly began to replace more time consuming formulations and methods. This product was the first in the marketplace to provide rapid mucin staining while simultaneously improving intensity. In October 1988, another great development was released as Muci-10 Plus which provided pathologists with even more intensely colored mucin in the same short period of just 10 minutes. Then, in April of 2000, the company released Muci-10 Concentrate which allows histotechnicians the ability to produce a ready to use stain solution in any volume desired by simply adding distilled water.
Despite these wonderful accomplishments and contributions to the industry, American MasterTech wasn't yet finished with these masterpieces. In the interest of providing additional value to its customers who use Mucicarmine, Muci-10 Carmine, and Muci-10 Plus, last year, the R&D department embarked on an investigation. Their goal was to research how small, previously made improvements in the manufacturing process could possibly have contributed to a more durable stain with a greater shelf life. The shelf life of most mucicarmine solutions in the market is generally 6 months, whereas AMT Mucicarmine stains have always marginally surpassed the industry average with a seven month shelf life. After extensive testing, and evaluation, it was discovered that various incremental improvements that the company had already made in its manufacturing processes over time as technological advances allowed, had in fact dramatically enhanced the durability of the Mucicarmine stain. Using retention samples from production batches, functional duration testing and spectro-analysis were performed on lots that had reached and exceeded their historical expiration dates. The research team was pleasantly surprised to discover that in all cases, excellent staining results were demonstrated by samples that had exceeded more than double their traditional shelf life. Functional testing continued at regular intervals until stain quality diminished to unacceptable levels. After all testing was completed and evaluated, it was determined that with proper storage and usage, the shelf life of MasterTech Mucicarmines could be reliably increased from seven to 14 months from the date of manufacture without any sacrifice in quality. Customers purchasing these products as well as the Muci Plus Stain Kit have already started benefiting from this increased shelf-life after the upgrade was formally adopted in the third quarter of 2014.
While product innovation is one key to the success of American MasterTech, tried and true products will always have a place in the histologist's repertoire. Even as increased use of automation continues to change the way histology is performed in the lab, there will always be a need for skilled histologists that are adept at performing non-routine manual staining procedures "on the bench". Whether those stains are performed on an automated machine or in a coplin jar, MasterTech products like the Mucicarmine family of stains will be there to empower laboratories with quality, consistency, and reliability.