ISSN:
1432-1432
Keywords:
Chirality
;
Asymmetry
;
Optical Activity
;
Parity Violation
;
Amino Acids
;
ß-Decay
;
Radiolysis
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Summary Experiments are described to test a theory for the origin of optical activity wherein the longitudinally polarized electrons resulting from parity violation during radioactive ß-decay, and their resulting circularly polarized Bremsstrahlung, might interact asymmetrically with organic matter to yield optically active products. The historical background to this subject is briefly reviewed. Our experiments involve subjecting a number of racemic and optically active amino acid samples to irradiation in a 61700 Ci90Sr-90Y ß-radiation source for a period of 1.34 years (total dose: 4.11 × 108 rads), then examining them for any asymmetric effects by means of optical rotatory dispersion and analytical gas chromatography. In the cases of D,L-leucine, norleucine, norvaline and proline as solids, of D,L-leucine in solution (neutral and as Na and HCl salts) and of D,L-tyrosine in alkaline solution no optical rotation was observed during ORD measurements in the 250–630 nm spectral region. While slight differences were noted in the percent radiolysis of solid D- (12.7%) and L-leucine (16.2%) as determined by GC, no enrichment of either enantiomer was found by GC analyses of irradiated D,L-leucine, either as a solid (13.7% radiolyzed) or as its Na salt (48.6% radiolyzed) or HCl salt (34.6% radiolyzed) in aqueous solution. Several explanations are offered for our experimental findings.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01732769
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