Mecember 17, 1952

Dr. Charles W. Todd

E. I. DuPont de Nemours & Co,
Chemical Dept/ Fypt. Station
Wilmington 98, Delaware

Dear Dr. Todd:

Perhaps you will recall your visit with me a year ago May. Have you
set up a program in microblological or bioshemical genetics?

I am writing in the hope that you may be able to refer me to a depart-
ment of your company that may be able to answer some technical questions,
I had thought that you might be sufficiently familiar with the problem
yourself that you could more properly phrase these questions to your
technical service.

My problem concerns the use of polyvinyl or other polymers in place
of glass for contadners in bacteriological work. There are three applica-
tions where glass ia unsatisfactory: 1) the storage of chemicals and solu-
tions to avoid ionic contamination; 2) the mailing of bacterial cultures,
especially pathogens, and 3) in centrifuge bottles, especially at higher
speeds or in larger volumes than 10 or 20 al. Commercially available
materials, as far as I know, are all unsatisfactory for bacteriological
work hecause they emanot be sterilized in the only way feasible for routine
work, by steam at 15 psi. I have heard vague reports that polyethenes
have now been produced which ean be sterilised by moist heat at temperatures
about 120-125° C, (intervals of 15 ~ 20 mina), but am not aware of their
commercial use for laboratory "glass"-ware. My most urgent need is for
centrifuge bottled of 50-500 ml. capacity. If necessary, I would use Bolling
water for sterilisation, but this would be less satisfactory. Can you help?

Yours aincerely,

Joshua Lederberg
Associate Professor of Genetics