Weizmann Institute scientists develop the first molecular keypad lock

January 24, 2007

Keypad locks, such as those for preventing auto theft, allow an action to take place only when the right password is entered: a series of numbers punched in a pre-set sequence. Now, a team of scientists at the Weizmann Institute of Science has created a molecule that can function as an ultra-miniaturized version of a keypad locking mechanism. Their work appeared in the Journal of the American Chemical Society (JACS).

The molecule, synthesized in the lab of Prof. Abraham Shanzer of the Organic Chemistry Department, is composed of two smaller linked units - fluorescent probes - separated by a molecular chain to which iron can bind. One of these probes can shine bright fluorescent blue and the other fluorescent green, but only if the surrounding conditions are right. These conditions are the keypad inputs: Rather than the electric pulses of an electronic keypad, they consist of iron ions, acids, bases, and ultraviolet light.

Shanzer and his group, which includes Drs. David Margulies, Galina Melman and Clifford Felder, have demonstrated in the past that such molecules can be used as logic gates, such as those that form the basis of computer operations. As opposed to electronic logic gates, in which electrical switches flip ON and OFF, the team's molecules, with various combinations of chemical and light inputs, can switch between colors and light intensities to perform arithmetic calculations.

The challenge in creating a keypad lock was in generating sequences that can be distinguished one from another. Entering the sequence 2+3+4 will yield the same result as 3+4+2 on a calculator, but a keypad lock set to one password (234) won't open for the other (342). The scientists found that by controlling the opening rate of the logic gate within the reaction time frame, they were able to produce different, distinguishable outputs, depending on the input order. By adding light energy, which also influences the molecules' glow, they were able to produce a molecule-size device that lights up only when the correct chemical 'passwords' are introduced. "It's just like a tiny ATM banking machine," says Shanzer.

Although these minuscule keypads are not likely to become a practical alternative to today's anti-theft devices, Shanzer believes this example of a molecular keypad lock - the first of its kind - will lead to new ideas and inventions in other areas such as information security and even medicine. "Faster and more powerful molecular locks could serve as the smallest ID tags, providing the ultimate defense against forgery." In the future, molecular keypads might prove valuable, as well, in designing 'smart' diagnostic equipment to detect the release of biological molecules or changes in conditions that indicate disease.
Prof. Abraham Shanzer's research is supported by the Nella and Leon Benoziyo Center for Neurological Diseases; the J & R Center for Scientific Research; the Helen and Martin Kimmel Center for Molecular Design; the Schmidt Minerva Center for Supramolecular Architectures; and Mr. and Mrs. Mordechai Glikson, Israel.

The Weizmann Institute of Science in Rehovot, Israel, is one of the world's top-ranking multidisciplinary research institutions. Noted for its wide-ranging exploration of the natural and exact sciences, the Institute is home to 2,500 scientists, students, technicians and supporting staff. Institute research efforts include the search for new ways of fighting disease and hunger, examining leading questions in mathematics and computer science, probing the physics of matter and the universe, creating novel materials and developing new strategies for protecting the environment.

American Committee for the Weizmann Institute of Science

Related Iron Articles from Brightsurf:

How stony-iron meteorites form
Meteorites give us insight into the early development of the solar system.

Bouillon fortified with a new iron compound could help reduce iron deficiency
Iron fortification of food is a cost-effective method of preventing iron deficiency.

Iron nanorobots go undercover
Customizable magnetic iron nanowires pinpoint and track the movements of target cells.

Iron deficiency in corals?
When iron is limited, the microalgae that live within coral cells change how they take in other trace metals, which could have cascading effects on vital biological functions and perhaps exacerbate the effects of climate change on corals.

Blocking the iron transport could stop tuberculosis
The bacteria that cause tuberculosis need iron to survive. Researchers at the University of Zurich have now solved the first detailed structure of the transport protein responsible for the iron supply.

Observed: An exoplanet where it rains iron
Nature magazine is publishing today a surprising study about the giant, ultra-hot planet WASP-76b in which researchers from the Instituto de Astrofísica de Canarias (IAC) have taken part.

An iron-clad asteroid
Mineralogists from Jena and Japan discover a previously unknown phenomenon in soil samples from the asteroid 'Itokawa': the surface of the celestial body is covered with tiny hair-shaped iron crystals.

It's Iron, Man: ITMO scientists found a way to treat cancer with iron oxide nanoparticles
Particles previously loaded with the antitumor drug are injected in vivo and further accumulate at the tumor areas.

The brain may need iron for healthy cognitive development
Iron levels in brain tissue rise during development and are correlated with cognitive abilities, according to research in children and young adults recently published in JNeurosci.

The regulators active during iron deficiency
Iron deficiency is a critical situation for plants, which respond using specific genetic programmes.

Read More: Iron News and Iron Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.