Weizmann Institute of Science scientists have recently developed a miniaturized version of a password recognition system, based on organic molecules. The molecular lock may, in the future, be an important tool in securing information, preventing forgeries and identifying biological molecules
Electronic locking systems, such as those used to protect cars against theft, allow certain operations to take place (for example, starting a car), only after the user enters a password, consisting of a series of numbers and/or letters, in a predetermined sequence. Weizmann Institute of Science scientists have recently developed a miniaturized version of a password recognition system, based on organic molecules. The molecular lock may, in the future, be an important tool in securing information, preventing forgeries and identifying biological molecules.
The molecular locking system is made up of two smaller units - fluorescent sensors - separated from each other by a molecular chain that can bind iron atoms. Under certain conditions, one of these sensors glows blue. In other conditions, the other sensor glows green. These conditions (presence of acids, bases, iron atoms, and radiation of ultraviolet light) are the inputs of the system, which play the role of electrical signals that operate in an electronic system with a keyboard.
The creators of the molecular locking system, Prof. Avraham Schnetzer, Dr. David Margulis, Dr. Galina Melman and Dr. Clifford Felder from the Department of Organic Chemistry at the Weizmann Institute of Science, previously demonstrated the use of organic molecules as logic gates, capable of being in "closed" and "open" states ” only under predefined conditions, similar to switches that allow computers to perform various calculations. The new molecular lock, however, can switch between different states of color and light intensities, depending on the combination of chemical and light inputs.
The challenge in inventing a lock that is operated using a keyboard is expressed in the need to create unique sequences ("passwords") that can be distinguished between them. For example, if you type in the calculator the sequence 2+3+4, you get the same result that is obtained as a result of typing another sequence: 3+4+2. But a lock with a keyboard, whose password is 234 will not open when the sequence 342 is typed.
Prof. Schantzer: "We discovered that controlling the opening rate of the logical gate, by determining the duration of the chemical reaction, and adding or not adding energy in the form of light radiation, allows the creation of different outputs (results)." In this way, the scientists were able to make the molecular structure they created glow only on the condition that the correct chemical "passwords" were "typed in", just as if it were a tiny ATM.
Prof. Schantzer believes that the molecular lock may lead to the development of new technologies in various fields such as information security and medicine. "Faster and stronger molecular locks may be used as identity tags that will enable protection against counterfeiting," he says. "They may also be important components in smart diagnostic systems that will recognize sequences of biological molecules, or a sequence of certain conditions that indicate the development of a certain disease."
