Gel cards

Technical file

Type of innovation: Reagent
Scope: Clinical Analysis
Innovation leader: Shared leadership
Year: 1995
Period: 1972-2002
Geographical scope: International
Economic impact: High
Level of innovation: Evolutionary
Patent: Yes
Interdisciplinary connections: -

Testing to ensure that transfused blood will be compatible with the blood of the transfusion recipient is a vital element of transfusion safety. It involves determining blood group according to the ABO system as well as identifying Rh-factor, which is particularly important in the case of pregnant women, due to the risk of incompatibility between mother and fetus.

Gel column agglutination

The development of the gel column agglutination technique was a significant milestone. Patented by Dr. Yves Lapierre in 1984, this method became the industry standard. The gel card was at the core of this technique. As the name suggests, this was a card holding six or eight microtubes, each containing a different blood-grouping reagent suspended in gel. Blood was pipetted into wells at the top of each tube. The samples were incubated and centrifuged, and the results read and analyzed.

Linking up with DiaMed

The world leader in this technology was a Swiss firm, DiaMed, who had patented it and began marketing cards in Europe and the USA in 1988. Diagnostic Grifols secured the rights to distribute DiaMed cards in Spain and Portugal and embarked upon an ambitious R&D program to automate card-based testing.

The commercial agreement between Grifols and DiaMed ended in 1996, when the Swiss company decided to open a subsidiary in Spain and distributed its cards through them.

(DiaMed continued to sell Grifols instrumentation used to perform the gel agglutination technique.)

The French connection

The loss of this partnership prompted Grifols to seek an alternative source of cards, and it signed a distribution deal with a French company, Diagast, manufacturer of DianaGel cards, showing an eight-well format, working with a specific set of reagents and allowing good readability.

However, there were drawbacks too. The eight-well format meant that some of the equipment used to handle the DiaMed cards was not compatible with it and there were concerns about the quality of the French cards.

Redesigning the gel card

Following a patent dispute between DiaMed and Diagast, the French company was forced to abandon its gel card activity. At this point, Grifols took a strategic decision: it purchased the technology from Diagast and embarked on its own program of manufacturing a redesigned and improved version of the card.

For months, the R&D team explored different gels, studied their behavior, and tracked down sources of errors. Dr. Víctor Grifols i Lucas even came out of retirement to share his experience. The new product combined an eight-column format with a new gel that offered greater sensitivity and specificity than the DianaGel cards. At the same time, the quality of the monoclonal antibodies and red blood cells that functioned as reagents was improved. The new product was christened the DG Gel card.

Of the three elements required to perform gel column agglutination – reagent red blood cells, instrumentation and cards – it was the last of these that posed the biggest challenge from a manufacturing perspective, and the development of a stable, high-quality product that could be manufactured in large volumes was the result of a series of innovations and improvements.