Chemo-spectroscopic sensor for carboxyl terminus overexpressed in carcinoma cell membrane

Certain carboxyl groups of the plasma membrane are involved in tumorgenesis processes. A gold core-hydroxyapatite shell (AuHA) nanocomposite is introduced as chemo-spectroscopic sensor to monitor these carboxyl groups of the cell membrane. Hydroxyapatite (HA) plays the role both of a chemical detector and of a biocompatible Raman marker. The principle of detection is based on chemical interaction between the hydroxyl groups of the HA and the carboxyl terminus of the proteins. The AuHA exhibits a surface enhanced Raman scattering (SERS) signal at 954 cm− 1 which can be used for its localization. The bio-sensing capacity of AuHA towards human skin epidermoid carcinoma (A431) and Chinese hamster ovary (CHO) cell lines is investigated using Raman microspectroscopic imaging. The localization of AuHA on cells is correlated with scanning electron microscopy, transmission electron microscopy and structured illumination fluorescence microscopy. This qualitative approach is a step towards a quantitative study of the proteins terminus.From the Clinical EditorThis method would enable further studies on the molecular profiling of the plasma membrane, in an attempt to provide accurate cell identification. Using a gold core-hydroxyapatite shell (AuHA) nanocomposite, the authors in this paper showed the feasibility of detecting and differentiating cell surface molecules by surface enhanced Raman scattering.

Graphical AbstractIn the dynamic of cellular biology an exact, rapid and sensitive apparatus to detect the carcinoma cell is still required. The method presented here detects the carboxyl terminals, overexpressed in carcinoma cell membrane, by means of a gold-hydroxyapatite (AuHA) chemo-spectroscopic sensor. In principle, the AuHA links to the C-terminus of the plasma membrane by releasing the water molecule between them. AuHA exhibits an enhanced Raman signal at 954 cm− 1, which indicates the presence of this interaction on the cellular membrane.Figure optionsDownload high-quality image (58 K)Download as PowerPoint slide