SCIENCE/TECHNOLOGY CONCENTRATES • Nitric oxide detected by chemfluminescence reaction A higjhly sensitive and selective method for detecting nitric oxide (NO) in biological samples has been devised by Masaaki Hirobe and colleagues in the faculty of medicine at the University of Tokyo [Anal. Chem., 65,1794 (1993)]. Nitric oxide has been reported to play an important role as a signal transmitter, not only in the vascular endothelium, but also in central and peripheral neurons and in phagocytic cells. The detection scheme is based on the chemiluminescence reaction between NO and the luminol-H202 system (luminol is 5-aminch23^IihydK>-l/4-phthala2inedionei and reportedly has a detection limit of about 100 femtomoles. The method overcomes limitations of other NO detection methods and opens the door to the possibility of doing online, continuous assay of NO in cell cultures and perfused organs, say the researchers. Moreover, die system is specificallyreactiveto NO, they say, so other nitrogen-containing compounds such as nitrites, nitrates, thio-nitroso, or endothetium-derived compounds do not interfere. Researchers have used the system to follow NO release and concomitant decrease in perfusion pressure upon administration of acetylcholine in isolated perfused rat kidney.
• Information service on Mosafety to be launched Development of a Biosafety Information Network & Advisory S«vice (BINAS) is being started this summer by the United Nations Industrial Development Organization (UNIDO). Its aim is to help meet an increasing need to standardizeregulatoryprocedures for release of genetically modified organisms into the environment Many industrialized countries have already developed standards and procedures for release of genetically engineered organisms, UNIDO explains, but many others—particularly in the Third World—have not BINAS, it says, aims to fill that gap. BINAS will have a steering committee of scientists and biosafety experts. The service will develop databases on existing guidelines, regulations and standards for use and release of genetically engineered organisms, and on nationalregulatoryauthorities and experts involved in field releases of transgenic organisms. It will also offer an electronic gateway to other related data banks.
• New publication addresses science, technology issaes Competitive Edge is about technology transfer. Launched last week in the U.K., it is designed to be "an effective interface between the technology provider and industry." Hurt's how the staff at AEA Technology sees its new glossy magazine. The company, which is the commercial arm of the U JC Atomic Energy Authority, a government agency, consults and performs research for a broad spectrum of science and engineering related organizations. Its expertise embraces such diverse fields as aerospace, computer technology, oil and gas, and pharmaceuticals. Competitive Edge, which will appear quarterly and be made available internationally free of charge, is described by Andrew Cruickshank, its editor, as a "horizontal" maga24 JULY 12,1993 CfcEN
zine cutting across a range of topics. It carries news and comment as well as feature articles on a variety of technical issues. Information is available from AEA Technology, 329 Harwell, Didcot, Oxfordshire OX11 ORA, U.K.; tele phone 235 432520, fax 235 432123.
• Immunoconjugate fights cancer via Trojan horse approach An immunoconjugate that uses a Trojan horse strategy to deliver an anticancer drug to cancer cells has been found to be highly effective in animal tests [Science, 261, 212 (1993)]. The use of immunoconjugates to fight cancer has been a long-sought goal, but results up to now have been disappointing, with most conjugates showing only about the same efficacy as the unconjugated drugs. Now, immunologists Pamela A. Trail and Karl-Erik Hellstrom and their coworkers at Bristol-Myers Squibb Pharmaceutical Research Institute in Princeton, N.J., Wallingford, Conn., and Seattle, have done better with a conjugate of the anticancer drug doxorubicin and a monoclonal antibody. The antibody binds an antigen found on many human cancer cells, after which it is rapidly internalized into acidic cell organelles. The unique feature of the conjugate is that the drug is released only after internalization, when a hydrazone bond between antibody and drug is cleaved in the acidic environment The conjugate causes complete regressions and cures of grafted human lung, breast, and colon cancers growing subcutaneously in athymic mice (mice whose immune systems are compromised to prevent tumorrejection),whereas doxorubicin only slows cancer progression or is ineffective. The conjugate also cures most athymic mice with extensively metastasized human lung cancer, and nearly all athymic rats with subcutaneous human lung cancer. Although studies on immunocompromised animals are not ideal for predicting anticancer activity in humans, the findings warrant clinical studies, the researchers say.
• Ghitin removes textile dyes from wastewater Chitin can be used to remove color from wastewater discharges at textile dyeing operations, according to researchers at North Carolina State University College of Textiles, Raleigh. The research team, headed by Samuel Hudson, an associate professor of textile engineering, chemistry, and science, and Brent Smith, a professor of textile chemistry, uses a bulk powdered form of the plentiful natural polymer, derived from crab shells, as afilteringagent in a laboratory decolorization module. "We're finding that a small amount of chitin powder will decolorize a lot of waste product, absorbing up to 20% of its weight in dye," Hudson says. "At $120 a ton, the use of bulk chitin powder is a cheap way to retrieve the color from wastewater." The dye-laden chitin powder, he adds, could be recycled for use in packaging materials or for commercial fuel logs. In North Carolina, 5 million lb of fabric are dyed daily, and textile-related industries discharge more than 64 million gal of water directly into the environment each day. The researchers note that regulation of dyes in wastewater is not yet mandated, but some mills are required to monitor and report color in their wastewater discharge.
