Mitomycin C determination using loop-column extraction: a rapid and sensitive high-performance liquid chromatographic assay for pharmacokinetic studies with Spherex starch particles

Voltammetric Determination of Mitomycin c Using a Chemically-Modified Glassy Carbon Electrode

An electrochemical method for the direct determination of mitomycin c (MMC), based on a multi wall carbon nanotube (MWNT)-modified electrode, has been developed. A well-shaped and highly sensitive oxidation peak at 0.79 V was observed on the MWNT-modified electrode for MMC. Further studies show strong evidence that MWNT-modified electrode significantly enhances the sensitivity of determination of MMC since the oxidation peak current of MMC increases remarkably, compared with that with a bare glassy carbon electrode. All the experimental parameters such as pH, scan rate, accumulation conditions, have been examined. A sensitive linear voltammetric response for MMC was obtained over the concentration range of 2.5 × 10-7-1.0 × 10-4 mol/l; the detection limit is 8 × 10-8 mol/l. Compared with other methods, this new-proposed method possesses advantages such as high sensitivity, fast response, low cost and simplicity. Eventually, the proposed method has been successfully employed to detect MMC in urine samples.

Pharmacokinetics of mitomycin C in patients after bolus injection and chemobolisation of the hepatic artery with Spherex starch particles

The pharmacokinetics of mitomycin C after chemobolisation of the common hepatic artery by micronized Spherex starch particles (mean particle size 30 microns) were investigated in 5 cancer patients. Bolus injection and simultaneous occlusion of the artery lead to a significantly lower systemic circulation of mitomycin C in the blood vessel system than after bolus injection without chemobolisation. The plasma concentration-time curves showed lower values in the alpha-phase in the presence of Spherex (co = 743 ng/ml) than without starch particles (co = 987 ng/ml). Accordingly, the AUC values were significantly lower too (AUC = 28.6 micrograms/ml.h with Spherex and 39.7 micrograms/ml.h without Spherex), thus leading to a lower systemic bioavailability of the drug and a higher local bioavailability in the tumor region. Elimination of mitomycin from the central compartment was similar for both administrations (t1/2 = 27 min with Spherex and 28 min without Spherex) and showed the characteristic profile of the substance. The clinical picture showed a milder toxicity with a certain loss of side effects. These results indicate a significant and desirable change in the pharmacokinetics of mitomycin C during the distribution phase into the tissue of patients.

[The effect of the vasoconstrictor glycylpressin on the bioavailability of mitomycin C]

During an intra-arterial chemotherapy of patients with liver metastases the plasma concentration-time curves of Mitomycin C (1) after occlusion of the common hepatic artery by the vasoconstricting agent Glycylpressin (2) were investigated. Vasoconstriction by 2 leads to significantly (p less than 0.01) lower blood levels of 1 in contrast to bolus injection of 1 without 2 under identical dosage regimens. This reduction of systemic availability of about 50% leads to a corresponding higher availability for the tumor region.