Identification of Tumor Cells through Spectroscopic Profiling of the Cellular Surface Chemistry

Abstract

A key challenge for molecular cancer diagnostics is the identification of appropriate biomarkers and detection modalities. One target of interest is the cell surface, which is involved in important steps of cancerogenesis. Here, we explore the feasibility of a label-free spectroscopic profiling of the cell surface chemistry for the detection of tumor cells. Vibrational spectra of the cellular surfaces of tumor and nontumor breast and prostate cell lines were recorded on silver nanoparticle substrates using surface-enhanced Raman spectroscopy (SERS). The quantitative analysis of the spectra revealed characteristic differences, especially in the spectral range between 600 and 900 cm−1. The detection of tumor-cell-specific differences in the recorded SERS spectra indicates the possibility of improving the precision of current cancer detection and staging approaches through a spectroscopic profiling of cell surface cancer biomarkers.

Functionalized arrays of Raman-enhancing nanoparticles for capture and culture-free analysis of bacteria in human blood

“…Recently, a type of SERS-active substrate with uniformly large and highly reproducible Raman-enhancing power has been developed by growing Ag nanoparticles on arrays of anodic aluminum oxide (AAO) nanochannels to take advantage of the sub-10-nm inter-particle gaps, which act as 'hot junctions' for creating the electromagnetic enhancement 4 . The high sensitivity and reproducibility of such a substrate-hereafter referred to as Ag/AAO-SERS substrate-facilitated the use of SERS for chemical/biological sensing applications [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22] . SERS of various types of bacteria including Gram-positive, Gram-negative and mycobacteria have been acquired and the response of bacteria to antibiotics has been examined 21 .…”

Probing real time gold nanostar formation process using two-photon scattering spectroscopy

“…Due to the intense electromagnetic field located around the pods, star shape gold nanocrystals are highly SERS active, which makes these particles very attractive for various real life applications [6][7][8][9][10]. Recently we and other groups have shown that, due to the strong absorption in near IR, asymmetric nanoparticles are potential candidates for novel cancer therapeutic agents through photo-thermal mechanism [11][12][13][14][15].…”

“…Recently we and other groups have shown that, due to the strong absorption in near IR, asymmetric nanoparticles are potential candidates for novel cancer therapeutic agents through photo-thermal mechanism [11][12][13][14][15]. In spite of the good progress over the past decade in the synthesis of gold nanomaterials of various sizes and shapes, an important challenge nanomaterials are facing in technological applications are due to the fact that the mechanisms underpinning these synthetic methods have evolved empirically and there is no accepted coherent mechanistic explanation to explain how shape control works [1][2][3][4][5][6]. The detailed understanding of the design and control parameters should have a profound impact on the engineering of the growth of nanoparticles to the desired size and shape, which is necessary for exploration of gold nanoparticles in a wide range of technological applications [6][7][8][9][10][11][12][13][14][15][16][17][18].…”

“…In noble metal gold nanoparticles, the coherent collective oscillation of electrons in the conduction band induces large surface electric fields, which greatly enhances the radiative properties of these nanoparticles [6][7][8][9][10][11][12][13][14][15][16][17][18][19]. As a result, the light scattering cross-section of metal nanoparticles are several orders of magnitude more intense than that of organic dyes, which makes it as an excellent candidate for novel contrast agents for optical detection [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19].…”

“…As a result, the light scattering cross-section of metal nanoparticles are several orders of magnitude more intense than that of organic dyes, which makes it as an excellent candidate for novel contrast agents for optical detection [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. As the particle size increases and interparticle distance decreases, coherent photoinduced nonlinear optical effect which shows a marked dependence on the interparticle distance and density can play a very important role.…”