Hard tissues spectroscopy

In this chapter, the main influences of temperature on the products obtained by hard tissues thermal processing are presented, highhghting the approaches and methods available nowadays. The main thermal analysis methods used to trace/identify the transformations that occur with the increase of the fabrication temperature are also emphasized. The correlation of such results with ones provided by complementary investigation methods, such as scanning electron microscopy, energy dispersive X-ray spectroscopy or X-ray diffraction, can enable a complex and insightful research on the evolution of the morphology and structure of hard tissues when subjected to heat-treatments. In the final part, results obtained for thermally treated bone samples are presented and an ample comparative discussion is carried out with respect to other reported studies. 

Connective tissues have often been reported in Raman and FT-IR images adjacent to epitheUum or carcinomas. Articular cartilage [15], ECM damage [16], and sarcoma, which is a neoplastic process originating within connective tissue [17], were studied by Raman spectroscopy. Applications of vibrational spectroscopic imaging to bone, which belongs to supportive connective tissue and is considered as hard tissue, are described in Chapter 4 of this book. 

Elements of Hard Tissues, Detectable by Vibrational Spectroscopy... 

Vibrational spectroscopy provides information on the functional groups present in the mineral and organic matrix components of hard tissues, as well as their molecular neighborhood [2,3]. The mineralized tissue components and properties that can be easily determined through both Fourier transform infrared (FT-IR) or Raman spectroscopic analysis and their biological significance are as follows ... 

Nixon277 compared atomic absorption spectroscopy, flame photometry, mass spectroscopy, and neutron activation analysis as methods for the determination of some 21 trace elements (<100 ppm) in hard dental tissue and dental plaque silver, aluminum, arsenic, gold, barium, chromium, copper, fluoride, iron, lithium, manganese, molybdenum, nickel, lead, rubidium, antimony, selenium, tin, strontium, vanadium, and zinc. Brunelle 278) also described procedures for the determination of about 20 elements in soil using a combination of atomic absorption spectroscopy and neutron activation analysis. 

The dielectric response of biological tissue has long been assumed linear. Thus an enzyme is treated as a hard sphere which relaxes linearly in an a. c. field at all but high field strengths [128]. In a suspension of cells, the electric field cannot penetrate to the interior of the cell at the low frequencies currently of interest in nonlinear dielectric spectroscopy [129], and is dropped almost entirely across the outer membrane of the cell which is predominantly capacitive at these frequencies, as was shown in Fig. 4. 

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