Diagnosis of liver cancer by FTIR spectra of serum

[Display omitted] •FTIR spectra of the serum from patients with liver cancer and healthy people were studied.•There were differences in the protein secondary structure of serum between the patients with liver cancer and healthy people.•Chemometrics performed on the SD-IR spectra in lipid range of 2900–2800 cm−1 could distinguish the serum of patients with liver cancer from that of healthy people.•FTIR spectroscopy might be developed as an effective method for the diagnosis of liver cancer. Liver cancer is the most common fatal malignant tumor in the world. Early diagnosis of liver cancer can improve the survival rate of the patients with liver disease. In this paper, Fourier transform infrared (FTIR) spectroscopy combined with curve fitting and chemometrics was used to distinguish the serum from patients from that of healthy people. The curve fitting results in protein range of 1700–1600 cm−1 showed that there were differences in the secondary structure of protein in serum between the patients with liver cancer and healthy people. Principal component analysis (PCA) in lipid range of 2900–2800 cm−1 could distinguish the serum of patients with liver cancer from that of healthy people. The first two principal components PC1 and PC2 explained 95% of the total data variance. The sensitivity and specificity of partial least squares discriminant analysis (PLS-DA) in lipid range of 2900–2800 cm−1 reached 92.85% and 95.23% respectively. It is shown that FTIR spectroscopy might be developed as an effective method for the diagnosis of liver cancer.