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Assessing HER2 expression in breast cancer cells holds significant diagnostic and prognostic importance. Traditional methods like immunohistochemistry and in situ hybridization suffer from low sensitivity and misclassification rates. In this frame, techniques such as vibrational microscopies can ensure, together with low costs and analytical speed, both high accuracy and precision. Herein, we propose a combined Raman and SERS approach for characterizing 4 breast cancer cell lines and normal cells with varying HER2 expression levels. We show that Raman spectroscopy offers a promising alternative, providing unique molecular fingerprints for cell types based on their biochemical signatures. Its non-invasive nature and ability to detect subtle changes in cellular metabolism make it ideal for cancer cell analysis. Coupled with machine learning techniques like PCA and LDA, Raman spectroscopy can classify different breast cancer subcategories accurately. Surface Enhanced Raman Scattering (SERS) further enhances sensitivity, allowing the detection of single molecules like HER2 receptors. Overall, our results enable fast screening of cancer subpopulation in terms of HER2 concentration and macromolecule cell content. Integration of Raman spectroscopy with SERS offers precise identification and opens avenues for personalized therapies.

Nucleic acids are essential biomolecules for the functioning of cells. In past years, nucleic acids have been assessing their role in prognostics and diagnostics. The progress of nanotechnology has allowed the fabrication of various type of nanostructured biosensors able to detect them with high sensitivity and specificity. Among the available sensing mechanisms, the sensor technology based on Surface-enhanced Raman Spectroscopy (SERS) is frequently preferred for identifying nucleic acids. In these sensors, natural or synthetic oligonucleotide sequences, acting as probes to hybridize the target molecules, are immobilized on a plasmonic sensing platform. In particular, aptamers, short DNA/RNA sequences, are emerging as new recognition elements for their chemical stability and specificity. Here, we focus on the combination of a specific type of aptamer, a molecular aptamer beacon, and nanostructured SERS biosensors for a sensitive detection of nucleic acids.

In this study, we report the results of two non-invasive optical methods, Raman microscopy (RM) and polarization-sensitive digital holographic imaging (PSDHI), for distinguishing prostate cancer cells from healthy ones. RM reveals cancer cells metabolize glucose faster, storing it as fatty acids and cholesteryl esters in lipid droplets (LDs). On the other hand, PSDHI shows significant morphological changes in LDs in glucose-incubated cancer cells, including number, volume, and refractive index. High birefringence in cancer LDs under perpendicular polarizations was observed, enabling fast discrimination with over 90% accuracy. PSDHI results align closely with Raman microscopy, suggesting its potential as a promising, high-speed technique for cancer screening purposes.

Metastasis stands as the leading cause of mortality among colorectal cancer (CRC) patients. Galunisertib (LY2157299, LY) is a small molecule demonstrating promising anti-cancer effects by targeting the Transforming Growth Factor-beta (TGF-β) pathway. This route plays a pivotal role in initiating the epithelial-to-mesenchymal transition (EMT), a critical process for metastatic spread. Unfortunately, LY chronic treatment causes undesired effects. To mitigate these side effects, nanoscale drug delivery systems have emerged as a transformative approach in cancer treatment, enhancing drug effectiveness while minimizing toxicity. In this study, we introduce a hybrid nanosystem (DNP-AuNPs-LY@Gel) comprising porous diatomite nanoparticles decorated with plasmonic gold nanoparticles (AuNPs), encapsulating LY within a gelatin shell. This multifunctional nanosystem demonstrates efficient LY delivery, EMT reversal in CRC 2D and 3D cultures, and anti-cancer effects in vivo. Moreover, the nanosystem allowed the quantification with sub-femtogram resolution of the drug intracellularly released using surface-enhanced Raman spectroscopy (SERS). The release of LY is triggered by CRC cell acidic microenviroment. Real-time monitoring of drug release at the single-cell level is achieved by analyzing SERS signals of LY within CRC cells. The heightened efficacy of LY delivery through the DNP-AuNPs-LY@Gel complex offers a promising alternative strategy for reducing drug dosages and subsequent undesired effects.

Plasmonic and Photonics applications of superconducting materials, suggested at first by the necessity to minimize the dissipative losses of conventional metals in the high frequency ranges, are topics of growing interest in Optics. In this perspective, GdSr2RuCu2O8-δ (Gd1212) Rutheno-Cuprate Superconductor presents very promising properties, showing both superconducting and magnetically ordered phases coexisting in the same cell. To investigate its features, the fabrication of macroscopic crystallographically oriented samples is necessary. The use of melt texturing techniques has shown to be among the most effective ways to achieve the best characteristics, although the fabrication of high-quality Gd1212 samples is intrinsically difficult. To reach a better understanding of Gd1212 incongruent melting reaction, a series of bulk samples annealed at temperatures below and above the melting temperature was prepared. Raman Microscopy and Mapping performed on molten and re-solidified samples revealed the presence of different phases, corresponding to those identified in our previous studies. These observations were also confirmed by XRD, TGA-DTA, and SEM+EDS characterisations. Secondary phases formation showed a strong dependence on the temperature of the annealing treatments. Susceptibility and magnetization measurements show both superconducting and magnetic transitions and a contribution of different spurious magnetic phases as suggested by EDS.

Here we have developed an advanced surface-enhanced Raman scattering (SERS) platform that enables the ultrasensitive, rapid and highly specific identification of tumour biomarkers in liquid biopsies. Our focus is on the detection of Thyroglobulin (Tg), the most important tumour biomarker for the diagnosis and prognosis of thyroid cancer. Specifically, SERS-active substrates fabricated by nanosphere lithography on chip or on tips of optical fiber (OF) were functionalised with Tg Capture antibodies. Gold nanoparticles were functionalized with Detection antibodies and conjugated with a Raman reporter. The sandwich assay platform was validated in the planar configuration and a detection limit of only 7 pg/ml was successfully achieved. A careful morphological characterisation of the SERS substrates allowed us to strictly correlate the coverage area with the Tg concentration. The same approach was successfully demonstrated in the washout of fine needle aspiration biopsies from cancer patients. The strategy was transferred to the Lab On Fiber (LOF) SERS platform and successfully used to detect Tg concentration. The proposed SERS-enhanced immunoassay platform has proven to be highly versatile and can be used with both microfluidic chip POC devices and SERS-OF-based optrodes to perform sensitive, specific and rapid ex vivo assays for Tg detection in liquid intraoperative biopsies.

A new, simple digital holography-based polarization microscope for quantitative birefringence imaging of biological cells is presented. As a proof of concept, two different class of cells have been characterized by polarization sensitive digital holographic imaging (PSDHI). These two cases study reported are: differentiation of leukaemia cells and identification of reacted sperm cells. Although further experimentation is necessary, the suggested approach could represent a prospective label-free diagnostic tool for use in biological and medical research and diagnosis.

Nanoscale delivery systems have been investigated for therapy due to their advantages, including the sustained delivery of drugs to cells and reduction of systemic toxicity compared to conventional treatments. However, their application is still hampered by experimental challenges, such as the investigation of the drug release in cells rather than in vitro. Here, we describe a hybrid nanoplatform for monitoring the drug release in living colorectal cancer (CRC) cells by Surface-Enhanced Raman Scattering (SERS). Specifically, the anticancer drug Galunisertib is encapsulated in diatomite nanoparticles (DNPs) decorated by gold nanoparticles (AuNPs) and capped by gelatin. The combination of DNP loading capacities with the Raman enhancement of Galunisertib provided by AuNPs enables bio-imaging and drug delivery without using fluorophores or markers, avoiding fluorescence-quenching issues. Thanks to the Raman enhancement of Galunisertib, the drug release profile is monitored and quantified in living cells by SERS with a femtogram scale resolution. When the gelatin shell is digested by proteases, Galunisertib is released and its SERS spectrum decreases, allowing real-time quantification in CRC cells. The therapeutic efficiency of the Galunisertib delivery platform offers an alternative route for lowering drug dose and toxicity.