Publications (5)11.26 Total impact

  • International Journal of Radiation Biology 07/1991; 60(1-2):195-9. DOI:10.1080/09553009114551841 · 1.84 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Biodegradable albumin microspheres have been prepared incorporating either 131I or 111In/111In. Using cDTPAA/albumin molar ratios of 1, 3 and 10, approx. 0.7, 2.1 and 7 molecules of DTPA could be coupled to an albumin molecule, labelling efficiency being constant over this range. Because 131I microspheres were more stable in plasma than the system labelled with radionuclides of indium it was selected for clinical evaluation: potential uses of this radiopharmaceutical are illustrated.
    International Journal of Radiation Applications and Instrumentation Part B Nuclear Medicine and Biology 02/1991; 18(7):687-94. DOI:10.1016/0883-2897(91)90006-7
  • 12/1990; 42(S1). DOI:10.1111/j.2042-7158.1990.tb14420.x
  • [Show abstract] [Hide abstract]
    ABSTRACT: Microspheres prepared from transferrin, haemoglobin and polyaspartic acid in admixture with albumin have been evaluated as alternatives to albumin systems as vehicles for the anti-cancer drug adriamycin. Electron microscopy has shown that transferrin and albumin/polyaspartic acid (195 mg/5 mg) microspheres are similar to albumin, possessing neither internal discontinuities nor surface pores, whereas haemoglobin microspheres exhibit both. Assessment of drug content revealed that transferrin (6.9 μ/mg) and haemoglobin microspheres (8.6 μ/mg) contained amounts of adriamycin that were not significantly different to albumin (9.0 μ/mg), whereas incorporation of polyaspartic acid into the albumin system led to an increase of 3–4 fold in native drug content. For albumin/polyaspartic acid microspheres values for drug content were in close agreement when assessed by HPLC and total fluorescence measurements, whereas for microspheres prepared from pure proteins total fluorescence values were 34–100% higher. An adriamycin-derived species was detected in albumin, but not albumin/polyaspartic acid microspheres, that did not co-chromatograph with native drug on thin-layer chromatography. Together these data indicate that a proportion of drug is present in other than native form in microspheres prepared from pure proteins.
    Journal of Controlled Release 12/1988; 8(2-8):93-101. DOI:10.1016/0168-3659(88)90035-1 · 7.26 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Doxorubicin (Adriamycin)-loaded casein and albumin microspheres, with diameters between 14 and 38 micron (50% weight average) were prepared by glutaraldehyde stabilization of the aqueous phase (containing protein and drug) of a water in oil emulsion. Physical properties, drug loading characteristics and release rates from microspheres in-vitro have been compared and correlated with effects on tumour growth when injected intratumourally in rats. Compared with albumin, the surface charge of the casein system was more negative and the microspheres exhibited a slower release of drug in-vitro. Both observations could be explained by the lower drug content of the casein system. There was evidence for the formation of a doxorubicin complex in the microspheres, the significance of which is not yet known. Casein microspheres containing 11 micrograms of doxorubicin had a similar inhibitory effect on tumour growth (growth delay = 20.7 days) to 85 micrograms of drug incorporated into albumin microspheres (growth delay = 18.6 days). The absence of a simple dose-response relationship shows that carrier matrix can influence potency of incorporated drug. The results are consistent with release rate of the drug from microspheres (obversely, rate of drug delivery to the tumour), being a determinant of potency in these systems.
    Journal of Pharmacy and Pharmacology 01/1988; 39(12):978-85. DOI:10.1111/j.2042-7158.1987.tb03144.x · 2.16 Impact Factor