Did You Read "Silent Spring"? The LKB 9000, the only Combined Gas Chromatograph-Mass Spectrometer currently being used in research throughout the world, unlocks the door to studies in the Hormonal control mechanisms of Developmental Processes. The post-embryonic development of insects is controlled by the molting hormone, ecdysone, the juvenile hormone and an adenotropic factor or brain hormone. Research on the juvenile hormone began in 1962 at the University of Wisconsin,where the hormone was extracted from the abdomens of adult male Hyalophora cecropia, a species of the giant silk worm moth. The yield of hormone was minute; in four years 300 ug, or approximately ten millionths of an ounce,were available for structural studies. In order to determine the structure of the hormone from this minute sample, Dr. C. C. Sweeley, University of Pitts burgh, used the technique of combined gas chromatography-mass spectrometry. He used the LKB 9000 Combined Gas Chromatograph-Mass Spectrometer to find that the juvenile hormone (JH) did not have a sesquiterpenoid structure but was methyl 10-epoxy-7-ethyl-3, 11-dimethyl2, 6-tridecadienoate.
The knowledge gained from such studies is applicable to the investigation of hormonal regulatory mechanisms in other animals including man. We can truly say that this is an example of the use of LKB instrumentation "In the Service of Science" Today in 38 research laboratories throughout the world, besides the University of Pittsburgh, the LKB Combined Gas Chromatograph - Mass Spectrometer is proving its excellence in Resolution, Detectability, Mass range, Speed of scanning and accuracy of Mass Determination.
CH 2 O-CH
CH2
CH
CH 2
N
CH
ο C-OCH3
Write today for fully illustrated documentation on the LKB 9000 Gas Chromatograph-Mass Spectrometer.
LKB INSTRUMENTS INC. • 12221 PARKLAWN DRIVE • ROCKVILLE Md. 20852
LKB
HQ LKB-PRODUKTER AB STOCKHOLM, SWEDEN INTERNATIONAL SUBSIDIARIES: L O N D O N , THE HAGUE, COPENHAGEN, VIENNA, STOCKHOLM Circle No. 65 on Readers' Service Card
84 A
•
ANALYTICAL CHEMISTRY
Circle No. 179 on Readers' Service Card
