Comparison of two radioimmunoassays and a microbiologic assay for bleomycin

Voltammetric Quantification of Anti-Cancer Antibiotic Bleomycin Using an Electrochemically Pretreated and Decorated with Lead Nanoparticles Screen-Printed Sensor

In this paper, we report a highly sensitive voltammetric sensor for the determination of the anti-cancer antibiotic bleomycin (BLM) based on a screen-printed carbon sensor that is electrochemically pretreated and decorated with lead nanoparticles in the sample solution (pSPCE/PbNPs). These sensor surface manipulations contribute to significant amplification of the analytical signal and improvement of its shape and repeatability. The effect of the electrochemical behavior of BLM on the pSPCE/PbNPs was examined by electrochemical strategies. CV, EIS, and XPS were used to compare the sensor surface modifications. The effects of the type and pH of the supporting electrolyte and the procedure parameters were optimized. The features of the proposed procedure include: (a) very low limits of detection and quantification (2.8 × 10^-11 and 9.3 × 10^-11 M, respectively), (b) linear ranges (1.0 × 10^-10-2.0 × 10^-9 M and 2.0 × 10^-9-2.0 × 10^-8 M, and (c) a high sensitivity of 0.32 µA/nM. The electrochemical sensor was successfully applied for the determination of BLM in wastewater and reference material of human urine samples.

Impedimetric detection of in situ interaction between anti-cancer drug bleomycin and DNA

Surface confined interaction of anti-cancer drug bleomycin (BLM) with nucleic acids: single stranded and double stranded DNA was investigated herein by using electrochemical impedance spectroscopy (EIS) technique in combination with a graphite sensor technology. The experimental conditions were optimized: such as, dsDNA concentration, BLM concentration and interaction time. The main features of impedimetric DNA biosensor, such as its detection limit and the repeatability, were also discussed. The in situ interaction of BLM with dsDNA was also tested impedimetrically in the absence or presence of other chemotherapeutic agents, such as mitomycin C (MC) and cis-platin (cis-DDP) for testing the selectivity.

Suppression of the mitogen response of normal lymphocytes by serum from patients with testicular germ cell tumors

Serum from seven of 15 patients with nonseminomatous testicular germ cell tumors impaired the transformation of lymphocytes from normal donors by phytohemagglutinin to less than 50% of that with addition to the cultures of normal AB serum. Similarly, serum from eight patients impaired the transformation by Staphylococcus aureus Cowan I. The impairment of the lymphocyte transformation did not correlate with the serum concentrations of alpha-fetoprotein (S-AFP) and human chorionic gonadotropin (S-HCG). The patients with metastases and serum that impaired lymphocyte transformation to less than 50% of that with addition of serum from the controls and the other patients survived in the same way (0.50 less than p less than 0.75, log-rank test). The prognosis of patients with testicular germ cell tumors seems not be influenced by S-AFP and S-HCG through an impact on lymphocyte functions determined as the response to the two mitogens.

Distribution of bleomycin in ethylnitrosourea-induced gliomas in rats

We used a microbioassay to study the distribution of bleomycin in rat brain tumors induced in newborn Sprague-Dawley rats with 1-ethyl-1-nitrosourea (ENU, 50 mg/kg s.c.). Upon suspected successful tumor induction bleomycin (0.1 g/kg i.v.) was administered, and 2 hr later bleomycin concentrations in major organs and tumor tissues were bioassayed using Bacillus subtilis PCI 219 IMC. To determine their histology, the tumors were stained by the immunofluorescence- or immunoperoxidase method using antiserum to astroprotein in addition to the conventional staining methods. There were 11 gliomas each of the brain and spinal cord, 14 schwannomas of the trigeminal nerve and 4 adenomas of the pituitary gland; they developed within 8 (gliomas), 7.3 (schwannomas) and 15 (adenomas) months on average after ENU treatment. The bleomycin concentration and the tumor:plasma concentration ratio were 7.69 +/- 2.84 micrograms/g and 0.13 +/- 0.05 (brain gliomas), 7.10 +/- 3.15 micrograms/g and 0.27 +/- 0.12 (spinal cord gliomas), 5.40 +/- 1.41 micrograms/g and 0.23 +/- 0.05 (schwannomas), 4.83 +/- 1.05 micrograms/g and 0.21 +/- 0.08 (adenomas). Normal brain- and spinal cord tissues scarcely contained bleomycin.