S Leimbrock

Publications (2)9.9 Total impact

• Article: Detection of bacterial endotoxin in antitumor agents.

  S E Siegel, R Nachum, S Leimbrock, M Karon
  [show abstract] [hide abstract]
  ABSTRACT: The Limulus amebocyte lysate assay was used to detect the presence of bacterial endotoxin in a variety of chemotherapeutic agents currently in use. Results were quantitated using a standard Escherichia coli endotoxin curve. Relative concentrations of endotoxin ranging from 0.1 to 63 ng/ml were detected in individual lots of L-asparaginase, 5-azacytidine, bleomycin, DTIC, actinomycin D, adriamycin, and vinblastine diluted to normal concentrations for injection. When multiple lots of a given drug were tested, at least one lot produced a negative assay, indicating less than 0.1 ng/ml of endotoxin in 50% of these drugs. All lots of cytosine arabinoside, cyclophosphamide, daunorubicin, vincristine, and streptozotocin tested had less than 0.1 ng/ml of endotoxin. Inactivation kinetics of the Limulus-positive drug material in dilute alkali solutions were identical to those of E. coli endotoxin. The Limulus lysate test is a rapid and specific method for the detection of small amounts of bacterial endotoxin contaminating parenteral preparations of antitumor agents.
  Cancer treatment reports 02/1976; 60(1):9-15.
• Source

  Available from: hematologylibrary.org

  Article: 5-Azacytidine: a new active agent for the treatment of acute leukemia.

  M Karon, L Sieger, S Leimbrock, J Z Finklestein, M E Nesbit, J J Swaney
  Blood 10/1973; 42(3):359-65. · 9.90 Impact Factor