Synthesis and application of doxorubicin-loaded silica gels as solid materials for spectral analysis.

A new approach to synthesis and the possibility of application of solid gel matrices containing the target analyte, a cancer drug-doxorubicin for the calibration of UV-vis spectrometers is presented. The doxorubicin-loaded gels were prepared by the acid-catalyzed sol-gel pre-doping method. The efficiency of doxorubicin encapsulation in gels by the sol-gel process was 100+/-1.2% (w/w). The amount of doxorubicin encapsulated per unit mass of the gel (1g) was found to be independent of the mass of the gel taken for analysis, which demonstrates the homogeneity of encapsulation of the drug in the gel matrix. The gelation process of doxorubicin in the sol was found to be both repeatable (R.S.D.=11.2% for n=80, confidence level P=95%) and reproducible (largest value of R.S.D.=4.8% for n=27, P=95%). The prepared doxorubicin-loaded gel matrices are characterized primarily by their lack of toxicity as compared to the toxic free form of doxorubicin as well as by high stability over a long-time span.