Brillouin and Raman microspectroscopy (BRamS) is a scattering technique that simultaneously assesses the mechanical and chemical properties of tissues with micrometric resolution. It has gained increasing attention in the biomedical field over the last decade and has been successfully used for both single-cell studies and whole-tissue characterization under physiological and pathological conditions. In addition, it is non-destructive, non-contact, and does not require labeling, offering the potential for future in vivo applications. The close interdependence between morphology, biochemistry, and mechanics is particularly relevant in the case of musculoskeletal tissues, where the complex structure is well-designed to ensure exceptional mechanical performance. The ability of tissues to resist and adapt to the mechanical and chemical stresses to which they are subjected depends to a large extent on maintaining the correct arrangement of all their components, starting from the microscopic level. In several common degenerative diseases, such as osteoarthritis (OA), the tissue architecture is destroyed by inflammatory processes, resulting in a rearrangement of its entire structure, leading to a complete loss of function and, often the need for prosthetic replacement. In this case, the use of minimally invasive techniques to explore the lesions could become a valuable resource for the surgeon in formulating a more precise diagnosis and, therefore, in providing more appropriate treatments. Here we discuss some of the results obtained by our group in characterizing human musculoskeletal tissue and detecting OA lesions in joints using BRamS.
The multiple scattering (MS) process affects the spectroscopic investigation and the optical imaging of opaque samples. In Brillouin spectroscopy, MS affects the extraction of reliable micromechanical parameters inducing the ill definition of the exchanged wavevector of the scattering process, q. Here, we propose a new experimental method called Polarization Gated Brillouin Spectroscopy (PG-BS) able to disentangle the MS and the ballistic contributions. The results obtained on milk, used as benchmark material, demonstrate both the capability and easy applicability of the proposed method. Exploiting PG-BS for different biological materials can open the route to new frontiers in Brillouin imaging of opaque samples.
A recently built set-up based on correlative Brillouin and Raman micro-spectroscopies, provides the simultaneous characterization of viscoelastic properties and chemical composition with subcellular resolution. Results obtained in cells and tissues show its diagnostic potential.
Tissue morpho-mechanics is gaining an increasing relevance in various fields, including biology, medicine, pathology, tissue engineering, and regenerative medicine, since it targets the relationship between morphological features and mechanical properties in biological tissues, which plays an important role in various biological processes including metastasis, wound healing and tissue regeneration. In particular, in every biological tissue, morphological, biochemical and mechanical properties are tightly connected and they influence each other in a correlative manner. For this reason, a correlative approach employing multiple techniques is ideal for targeting tissue morpho-mechanics with an optical approach. Here we report a correlative study performed by optical microscopies, disclosing the supramolecular collagen morphology correlated with its biomechanical and biochemical analyses. In particular, using human corneal tissue as a benchmark, we correlate Second-Harmonic Generation maps with mechanical and biochemical imaging obtained by Brillouin and Raman micro-spectroscopy, demonstrating that the peculiar mechanical functionality of so-called sutural lamellae originates from their distinctive supramolecular organization. A theoretical model based on the ultrastructural symmetry of corneal lamellar domains provides the interpretation of the experimental data at the molecular scale. The proposed methodology opens the way to the non-invasive assessment of tissue morpho-mechanics and holds the potential to be applicable to a broad range of biological and synthetic materials.
Tissue morpho-mechanics is gaining an increasing relevance in various fields, including biology, medicine, pathology, tissue engineering, and regenerative medicine, since it targets the relationship between morphological features and mechanical properties in biological tissues, which plays an important role in various biological processes including metastasis, wound healing and tissue regeneration. In particular, in every biological tissue, morphological, biochemical and mechanical properties are tightly connected and they influence each other in a correlative manner. For this reason, a correlative approach employing multiple techniques is ideal for targeting tissue morpho-mechanics with an optical approach. Here we report a correlative study performed by optical microscopies, disclosing the supramolecular collagen morphology correlated with its biomechanical and biochemical analyses. In particular, using human corneal tissue as a benchmark, we correlate Second-Harmonic Generation maps with mechanical and biochemical imaging obtained by Brillouin and Raman micro-spectroscopy, demonstrating that the peculiar mechanical functionality of so-called sutural lamellae originates from their distinctive supramolecular organization. A theoretical model based on the ultrastructural symmetry of corneal lamellar domains provides the interpretation of the experimental data at the molecular scale. The proposed methodology opens the way to the non-invasive assessment of tissue morpho-mechanics and holds the potential to be applicable to a broad range of biological and synthetic materials.
Tissue morpho-mechanics is gaining increasing in various fields, because it targets the relationship between morphological features and mechanical properties in biological tissues, which plays an important role in various fields including biology, medicine, pathology, tissue engineering, and regenerative medicine. The intimate connection between morphological, biochemical and mechanical properties in biological tissues requires a multimodal correlative approach for their exhaustive investigation. In this study, we used Second-Harmonic Generation in combination with Brillouin and Raman micro-spectroscopy in order to correlate collagen morphology at the ultrastructural level with its biomechanical and biochemical features. In particular, by imaging human corneal tissue samples with our multimodal approach, we demonstrated that the peculiar mechanical properties of corneal lamellae in the anterior portion of the corneal stroma are due to a different supramolecular organization, rather than to a different biochemical composition. This result opens new insights in the study and interpretation of corneal biomechanics thanks to the possibility of non-invasively correlating lamellar morphology with visco-elastic properties. The proposed method opens the way to the non-invasive assessment of corneal morpho-mechanics and holds the potential to be used for both diagnostic and follow-up purposes in pathologies that affect corneal biomechanics.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.