November 18, 1943
Dr. A.N. Richards
Committee on Medical Research
2101 Constitution Avenue
Washington 25, D.C.
Dear Dr. Richards:
I am leaving for Washington on Sunday, and hope to have the pleasure of talking to you for a few minutes. I shall
arrive in Washington on the afternoon of Thanksgiving day, and shall attend a meeting of Division 8 of the NDRC on Friday,
November 26. This meeting will, I think, be over by 4:00 or 4:30, so that, if you should be in town and be free at the time,
I could come to your office at 5:00 or 5:30. I have made no appointments for Saturday; my train leaves at 5:30 Saturday afternoon.
I would like to tell you about an idea which Dr. Campbell and I have had about penicillin. It occurred to both of
us that the efficacy of penicillin might be increased considerably if it could be held in the blood stream for a longer period.
This might be accomplished by coupling it to a protein molecule, large enough not to leak out through the kidneys. Human globulin,
for example, might be used as this protein. Whether the coupling could be done in such a way as to leave the effectiveness
of the penicillin molecule unimpaired could be found only by experiment. The work along these lines could be done most effectively,
of course, with knowledge of the structure of penicillin, but some coupling methods might be tried even in absence of this
knowledge. The possibility also exists that, even though penicillin itself could not be coupled to protein without loss of
activity, some active analog might be synthesized (after the structure of penicillin has been determined) and coupled without
loss of activity.
We would be interested in doing work of this sort because of our experience in coupling molecules to proteins. Our
blood substitute work is moving alone smoothly and we are beginning to think about other possible jobs. Our program of work
in immunochemistry in general is making satisfactory progress, but our artificial antibodies, although they show some productive
activity in animal experiments, are not yet sufficiently effective to be of practical value.