NEWS OF THE WEEK
FACILITY SET FOR NEW COOLANT
H
I STO CK
Automakers such as General Motors have backed HFO-1234yf.
Carmakers adopted HFC-134a in the 1990s to replace the chlorofluorocarbon CFC-12, which contributed to ozone layer depletion, but the replacement turned out to be a significant contributor to global warming. Laws in both the U.S. and Europe are now steering autoFLUOROCHEMICALS: Honeywell makers away from HFC-134a. Both ozone- and globalto build first U.S. plant for warming-friendly, HFO-1234yf is a good alternative, replacement auto refrigerant Honeywell says. Not every carmaker is behind it, however. F HFO-1234yf is mildly flammable, and Daimler F ONEYWELL IS PLACING a $300 miland some other German firms are concerned lion bet that automakers will adopt a new that it could cause a fire in a collision. They are F F fluorinated refrigerant for car air-condiplanning to use CO2 as their coolant chemical. HFO-1234yf Honeywell insists that HFO-1234yf poses no adtioning systems. The New Jersey-based technology conglomerate says ditional risk to first responders at an accident site. it and its raw material suppliers will spend that much on Despite the reluctance of German firms, Honeywell North America’s first commercial plant seems confident it can line up enough customers to for the hydrofluoroolefin HFO-1234yf. The justify a commercial facility, notes Ray K. Will, a direcchemical is a replacement for the hydrotor with the consulting firm IHS Chemical who covers fluorocarbon HFC-134a used as the coolthe fluorochemicals industry. “CO2 may be okay in Gerant in most auto air conditioners today. many,” Will says, “but during the summer in Houston The facility is set to open in 2016 at a or Riyadh you need the performance of HFO-1234yf.” site in Geismar, La., where Honeywell Honeywell codeveloped HFO-1234yf with DuPont. manufactures other fluorinated comToday, the world’s main commercial source of the pounds. Kenneth Gayer, vice president product is a Chinese firm that began production last of Honeywell Fluorine Products, says the year in a venture with DuPont. Honeywell’s commitplant’s exact size will depend on supply ment to build its own plant in the U.S. is telling, Will agreements the firm is now hammering says. “Honeywell has proven itself to be aggressive in out with major auto industry customers. this market.”—MICHAEL MCCOY
NONDESTRUCTIVE SAMPLING OF A CELL ANALYTICS: Robotic nanopipette gently removes femtoliter samples from cells without killing them
ACS NANO
A nanopipette with a 100-nm-wide tip (inset) extracts tiny samples from living cells.
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HEN SCIENTISTS INVESTIGATE the in-
ner contents of a cell, the methods they use often end up killing it. Now, bioengineers have introduced a kind of cellular biopsy—a system to extract femtoliters of material from a cell without destroying it (ACS Nano 2013, DOI: 10.1021/nn405097u). The technique permits repeat sampling of a living cell, enabling study of its dynamic biochemistry over time. Current methods that use micropipettes or microdissection to obtain a cell’s contents are generally fatal to the cell. A few groups have found less harmful ways to specifically remove RNA. Yet a method for general extraction from a live cell has remained CEN.ACS.ORG
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elusive, says Nader Pourmand, a biomolecular engineer at the University of California, Santa Cruz. Pourmand and his group customized a scanning ion conductance microscope (SICM) to guide a glass nanopipette into single cells and draw out material. First, the researchers roughly align the nanopipette over a bed of cultured cells. The SICM computer then takes over, guiding the nanopipette toward the cell of interest. The nanopipette stops just before touching the cell, then plunges down 1 µm to pierce the cell membrane. Once in, the computer applies a negative voltage across the 100-nm-wide pipette tip. The voltage alters the surface tension between an organic solution in the nanopipette and the cell’s aqueous cytoplasm. As a result, the nanopipette sucks about 50 femtoliters of the cell’s contents. After sampling, the cells maintain their shape and membrane integrity, even after 10 punctures. To show that their method could extract useful material from different regions of a cell, the researchers plucked and sequenced cytoplasmic messenger RNA from human cancer cells and mitochondrial DNA from human fibroblasts. “You can extract anything. That is the beauty of it,” comments Yuri Korchev, a professor of biophysics at Imperial College London. Such flexibility permits many different types of measurements, such as single-cell diagnostic tests or drug screening, he says. “I see a hundred possibilities.”—LOUISA DALTON, special to C&EN
DECEMBER 16, 2013
