Effect of short-term formaldehyde fixation on Raman spectral parameters of bone quality.

摘要: Medical knowledge of the skeleton including its structures has improved constantly over past decades. Advanced imaging methods, mechanical testing and optical techniques have revealed insights into bone architecture composition. Most these advancements were possible due to ex vivo investigation biological tissues. Investigations fresh tissue are generally preferred preserved or fixed samples. However, chemical fixation is sometimes inevitable histological procedures logistical reasons. The aim this study was investigate whether short-term with formaldehyde affects quality parameters obtained from Raman spectroscopy if effects last for intermediate sample storage several hours. As induces cross-links organic components in tissue, we hypothesized that collagen-related particularly affected. Femurs eight 17-week-old C57BL/6 mice extracted divided two groups (N  =  8  /  group). Samples first group by immersion 4% (PFA-solution) 12 h at 4°C (fixed group) while samples second left untreated (unfixed group). performed, repeated after 4 h, assess time influenced results. Based on resultant spectra, mineral-to-matrix ratio, carbonate-to-phosphate carbonate-to-amide I mineral crystallinity collagen maturity determined. Carbonate-to-phosphate ratio only parameter showing a significant difference between subsequent measurements. For both groups, ratios showed decrease carbonate substitution compared measurement (percentage decrease: 3.1% fixed, 4.7% unfixed). Collagen samples, which formaldehyde, significantly lower than fresh, unfixed difference: 3.8%). Our shows able detect changes structure initiated minimally influencing material properties measured spectroscopy.