Abstract:

Objective To identify normal breast tissue and breast invasive ductal carcinoma (IDC) tissue by shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS),and to explore the biological characteristics of IDC and the identification method by discussing its spectroscopy characteristics.
Methods The frozen section of breast tissue from 24 patients (female,aged 27-59 years) underwent routine surgical resection were obtained.9 cases of normal breast tissue and 15 cases of IDC breast tissue were detected by Raman spectroscopy and then SHINERS technique was utilized.A total of 263 Raman spectra and 249 SHINERS spectra were obtained.All the spectra were dealt with baseline corrected by fitting and subtracting a third-order polynomial and then smoothed with a 15-point Adjacent-Averaging.Results The characteristic peak of normal breast tissue appeared at 1 090,1 157,1 262,1 300,1 442,1 658,1 745,and 1 874 cm-1.After adding shell-isolated nanoparticles (SHINs),some peaks shifted at 2-3 cm-1,and the relative strengthes of 1 090 and 1 157 cm-1 were significantly increased,and the  characteristic peak at 1 496 cm-1 appeared.The Raman spectroscopy showed there were more nucleic acid ch
aracteristic peaks (including 878,1 086,1 157 cm-1) in the breast IDC tiss
ue;
after
adding SHINs,the relative strengthes of 1 004,1 157,1 526,and 1 658 cm-1 were  increased,the characteristic peak of lipid at 1 745 cm-1 and 1 442 cm-1
 stemmed from the C=O and CH2 stretching vibration.Compared with the normal breast tissue,the breat IDC tissue showed a blue shift of 2-3 cm-1.The characteristic peaks of nucleic acid had the blue shift from 1 086 cm-1 to 1 090 cm-1,and the characteristic peak of β-carotene emerged at 1 527 cm-1.
Conclusion Raman spectra can discover the differences of the characteristic peaks of DNA,β-carotene,and protein between breast IDC and normal breast tissues;SHINERS can distinguish breast IDC tissue from normal breast tissue successfully.

Key words: breast neoplasms, Raman spectroscopy, surface enhanced Raman spectroscopy, invasive ductal carcinoma