Papers by Author: Ioan Notingher

Abstract: Septal cartilage is widely used for the repair of soft tissue defects in the head, neck and nose. Tissue Engineering techniques are being investigated to create cartilage in vitro by seeding appropriate cells on resorbable scaffolds. In this study, human chondrocytes were cultured on macroporous bioactive glass foam scaffolds. The aim was to investigate how Raman spectroscopy could be used as a non-invasive technique to monitor the response of chondrocytes to a 3D scaffold in real time. The spectra were compared to scanning electron microscope (SEM) micrographs and immunohistochemistry results.

Abstract: The Classical Least Square (CLS) fitting method was used to analyze the Raman spectra of living cells with the aim of identification of new phenotype-specific spectral markers for osteoblasts. The following chemicals were used for the CLS model: DNA, RNA, serum albumin, chymotrypsin and phosphatidyl choline. In this study we analyzed primary mature osteoblasts as well as two other cell types used as potential sources of osteoblasts: embryonic stem cells and fetal bone cells. The results obtained suggest that the Raman spectra of the cell types can be well approximated with a linear combination of the Raman spectra of the biopolymers used in the CLS model. The relative concentrations of the CLS components varied significantly between cell types, indicating that this analytical method could be used for phenotypic identification of osteoblasts.

Abstract: We present a new bio-photonic method based on Raman spectroscopy able to characterize living cells in in-vitro cultures. The main advantages of this technology are: no labels or other contrast enhancers are required; provides real-time analysis; cells can be maintained in physiological conditions during the measurements; no cell-damage is induced during the measurements; it is rich in information about the biochemical composition of the cell. The results show that this spectroscopic method can be used to study the most important cellular functions involved in cell-biomaterial interactions, such as cell death, differentiation, de-differentiation and mineralization. The method offers the potential for studying cell-bioceramics interaction and reduce the need of animal testing until the final steps of proving efficacy prior to clinical trials.

Abstract: A new type of ceramic-polymer biomaterial having excellent apatite-forming ability in simulated body fluid (SBF) was prepared by hot-pressing a mixture consisting of poly(-L-lactic acid)(PLA) and calcium carbonate (vaterite). The composite containing 30% vaterite showed no brittle fracture behavior and comparably high bending strength of ~50 MPa. Apatite layer of several micrometers in thickness formed on its surface after soaking in SBF at 37°C only for 1 day. Osteoclast culture tests showed that the composite coated with apatite has excellent bioresorbability. After incubation of human osteoblasts, mineralized bone nodule formation was seen on the surface.