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The first molecular keypad lock

Journal of the American Chemical 中国365bet中文官网

How can defense or intelligence agencies safeguard the security of top-secret data protected by a computation device the size of a single molecule? With cryptography approaching that sobering new era, scientists in Israel reported development of what they term the first molecular system capable of processing password entries. Abraham Shanzer and colleagues described their 鈥渕olecular keypad lock鈥� in the Jan. 17 issue of the weekly Journal of the American Chemical 中国365bet中文官网. Electronic keypad locks long have been fixtures on home security systems and other devices that require a password.

The study, however, described a keypad lock based on molecules that fluoresce only in response to the correct sequences of three input signals.

鈥淏y harnessing the principles of molecular Boolean logic, we have designed a molecular device that mimics the operation of an electronic keypad, a common security circuit used for numerous applications in which access to an object or data is to be restricted to a limited number of persons,鈥� the researchers state. 鈥淭he development of a molecular-scale keypad lock is a particularly attractive goal as it represents a new approach to protecting information at the molecular scale.鈥� The researchers cite DNA-microdot encryption as a complementary approach, which in combination with their molecular lock might provide an unbreakable protection against forgery.

Explosive discovery on genetically engineered tobacco plant

Environmental Science & Technology

Tobacco may be bad for human health, but a new study reported that a genetically engineered tobacco plant may be very good for the environment. It shows promise for cleaning up soil contaminated with TNT, a widely used military explosive. The study appeared in the Aug. 15 issue of ACS鈥� Environmental Science & Technology, a semi-monthly journal.

Antonio J. Lopez-Farre and Carlos Macaya and colleagues described what they term the first use of a powerful technology called two-dimensional electrophoresis to study changes in different proteins present in two groups of patients with coronary artery disease, the underlying cause of most heart attacks. One group of patients was aspirin-sensitive and the other had aspirin resistance.

The researchers found increased levels of three proteins involved in the binding of vitamin D in patients with aspirin resistance. They also described additional laboratory experiments demonstrating that those proteins can inhibit aspirin鈥檚 effects in preventing blood clots. 鈥淭hese results may aid future development of more effective therapies for aspirin-resistant patients,鈥� the study concludes.

Toward a faster prenatal test for Down syndrome

Analytical Chemistry

Scientists in California reported an advance toward rapid testing for pre-natal detection of Down syndrome and other birth defects that involve an abnormal number of chromosomes.

In a study that appeared in the Oct. 1 issue of ACS鈥� journal Analytical Chemistry, Stanford University bioengineering professor and Howard Hughes Medical Institute researcher Stephen R. Quake and his graduate student H. Christina Fan point out that most existing pre-natal tests depend on a technique termed karyotyping. It requires a two-week wait for anxious parents, while cells taken with amniocentesis or chorionic villus sampling are grown in laboratory culture and analyzed.

Laboratory studies with the new method produced accurate results within two hours. The test is a variation of the famed polymerase chain reaction (PCR) 鈥� the basis of the genetic engineering revolution 鈥� which produces thousands of identical copies of minute samples of DNA.

Using a technique known as the digital polymerase chain reaction, Quake and Fan replicated DNA from two cultures of cells growing in the laboratory. One consisted of a normal human cell line and the other had human cells with the Down variant. The digital

PCR process allowed the researchers to count DNA molecules from the samples, substituting for the two-week cell culture process traditionally needed to produce enough DNA for karyotyping. With the precision derived from counting individual DNA molecules, researchers then were able to move ahead without delay and determine which samples had the extra chromosome that indicates Down syndrome.

*The research in this release is from a copyrighted publication, and stories must credit either the journal by name or the American Chemical 中国365bet中文官网.