Boston : MIT researchers have developed a compact, portable pharmaceutical manufacturing system that can be reconfigured to produce a variety of drugs on demand.

Just as an emergency generator supplies electricity to handle a power outage, this system could be rapidly deployed to produce drugs needed to handle an unexpected disease outbreak or to prevent a drug shortage caused by a manufacturing plant shutdown, researchers said.

"Think of this as the emergency backup for pharmaceutical manufacturing," said Allan Myerson, a professor at Massachusetts Institute of Technology (MIT).

"The purpose is not to replace traditional manufacturing; it's to provide an alternative for these special situations," said Myerson.

Such a system could also be used to produce small quantities of drugs needed for clinical trials or to treat rare diseases, said Klavs Jensen, a professor at MIT.

"The goal of this project was to build a small-scale, portable unit that was completely integrated, so you could imagine being able to ship it anywhere," Jensen said.

Traditional drug manufacturing, also known as "batch processing," can take weeks or months.

Previously, a team that included Jensen, Myerson and Timothy Jamison, the head of MIT's Department of Chemistry, demonstrated a larger prototype for the continuous integrated manufacturing of drugs from chemical synthesis to tablets.

In the new research, the researchers built on what they learned from the previous project to create a much smaller, transportable device.

The new system can produce four drugs formulated as solutions or suspensions Benadryl, lidocaine, Valium and Prozac. Using this apparatus, the researchers can manufacture about 1,000 doses of a given drug in 24 hours.

Key to the continuous system is the development of chemical reactions that can take place as the reactants flow through relatively small tubes as opposed to the huge vats in which most pharmaceutical reactions now take place.

Traditional drug manufacturing, also known as "batch processing," is limited by the difficulty of cooling these vats, but the flow system allows reactions that produce a great deal of heat to be run safely.

The chemical reactions required to synthesise each drug take place in the first of two modules. The reactions were designed so that they can take place at temperatures up to 250 degrees Celsius and pressures up to 17 atmospheres.

By swapping in different module components, the researchers can easily reconfigure the system within hours to produce different drugs.

In the second module, the crude drug solution is purified by crystallisation, filtered, and dried to remove solvent, then dissolved or suspended in water as the final dosage form.

The system could be used to make small amounts of drugs that would be too expensive to make in a large-scale plant.

The study was published in the journal Science.