Pharmaceutical Glass: The Less Alumina, The Better

With Asolvex, the trademark given to its new low-alumina glass, Saint-Gobain Desjonquères (Saint-Gobain Desjonqueres Pharmaceutical Division) has scored a decisive point in the pharmaceuticals segment. Here's how and why.

Three-Fold Reduction in Alumina Content
Alumina (or aluminium oxide), a natural constituent of glass, has always caused problems for the storage of blood plasma and other sensitive substances used in the treatment of serious illnesses. Even with USP Type 1 glass (see "Three Types of Glass," below)—the most "advanced" type of pharmaceutical glass—enough alumina escapes (by leaching) to alter the quality of certain substances over time.

"Pharmaceutical companies, especially in the United States, asked us about this problem a number of years ago, and our R&D department has been working to find a solution ever since," explains Laurent Zuber, sales manager for the pharmaceuticals market at Saint-Gobain Desjonquères.

"Of the five manufacturers of molded containers made of type 1 glass (two in the United States and three in Europe), Saint-Gobain Desjonquères is currently the only one to have reduced the leaching of alumina." We have achieved a three-fold reduction, " says Zuber, "leaving only 2% aluminium oxide."

Full Scale Launch Set for Early 1999
Although industrial-scale testing began in late 1997, regulations require manufacturers to give customers nine months' notice in advance of the commercial launch of this type of glass. Accordingly, Asolvex will not replace existing products until 1999. "Our markets are essentially concentrated in the United States, England, and the Nordic countries, reflecting the locations of major laboratories that use Type I glass containers," Zuber explains. The main uses are as containers for blood constituents (e.g., albumin); nutritional formulations such as those given to premature infants; products used in biology and cancer research; and for biotechnology applications. Ultimately, the target is to capture a third of the Americain market, against the current 15% share.

Three Types of Glass

• USP Type 1. Also known as "body neutral," type 1 is a borosilicate glass with good chemical resistance. It is used for pharmaceuticals requiring the least reactive containers
  
• USP Type 2. A treatment applied to the internal surface of the glass reduces ion exchange, making this category suitable for solutions administered intravenously.
  
• USP Type 3. This is a soda-lime glass and is the type most commonly manufactured. It is used for syrups and other liquid formulations.