Surface‐enhanced Raman scattering of secretory proteins for the cytotoxicity analysis of low‐dose doxorubicin

The cytotoxicity and dose of anticancer drugs must be strictly controlled to achieve better therapeutic effects while reducing side effects. Here, surface-enhanced Raman scattering (SERS) of secretory proteins was employed to analyze the cytotoxicity of doxorubicin at low dose (0.01 and 0.05 mu g/ml), which could not be evaluated by the conventional methyl thiazolyl blue tetrazolium bromide (MTT) assay. The variances of SERS signals of secretory proteins between control and doxorubicin-treated groups became greater gradually with the increase of doxorubicin dosage, and the SERS bands at 660 and 1,375 cm(-1)were closely related to the cytotoxicity of doxorubicin. Combined with principal component analysis and linear discriminant analysis (PCA-LDA), SERS spectra of secretory proteins from different drug dose groups could be distinguished with high sensitivity (97.2%) and accuracy (84.7%), demonstrating promising potential as an alternative nanotechnology for cytotoxicity analysis of low-dose anticancer drugs.