Collagen extraction method

In addition, our results suggest that removal of hpids improves both yield characteristics and elemental characteristics. Recent work by Liden et al. (1995) suggests that the methanol-chloroform method used here is more effective than other methods, such as treatment with NaOH solution, or the maintenance of an acidic environment and ultrafiltration of products during collagen extraction. It is speculated that the presence of hpids in archaeological bone samples may interfere with the acid hydrolysis of protein during... 

Brown, T.A., Nelson, D.A., Vogel, IS. and Southern, J.A. 1988 Improved collagen extraction by modified Eongin method. Radiocarbon 30 171-177. 

Longin, R. 1971 New method of collagen extraction for radiocarbon dating. Nature 230 241-242. 

Longin, R., New Method of Collagen Extraction for Radiocarbon Dating, Nature. 1971, 230, 241-242. 

Another major problem associated with the extraction of DNA from archaeological specimens is that the procedure often co-extracts impurities that can later complicate, or prevent, the study of the extracted DNA by inhibiting PCR amplification (reviewed by 5). Commonly encountered inhibitory substances found in aDNA extracted from teeth, bones, mummified tissue, and coprolites include humic acids, ftilvic acids, tannins, porphyrin products, phenolic compounds, hematin, and collagen type I (37—42). The formation of Maillard products, commonly encountered in coprolite samples, can also prevent PCR amplification by causing DNA to become inaccessibly trapped in these sugar-derived condensation products (12). As the negative results in many aDNA studies are attributed to the presence of PCR inhibitors, our extraction method outlined below pays particular attention to the problem and offers a simple test for the presence of PCR inhibitors in DNA extracts. 

In conclusion, nitrogen/carbon ratios combined with quantitative amino acid analyses could determine the level of impurities that may co-exist with fossil bone collagen and could help in selecting the optimum method of collagen separation. An extraction method may be successful in some cases but could fail to remove the impurities from bone collagen in other samples. Chemical analysis of the impurities and their radiocarbon dates also should be obtained. 

Aramwit, P., Kanokpanont, S., Nakpheng, T., Srichana, T., 2010. The effect of sericin from various extraction methods on cell viability and collagen production. International Journal of Molecular Sciences 11 (5), 2200—2211. 

The collagen content of the thoracic aorta was expressed in mg/100 mg of dry, lipid-free aortic tissue. This was done by using the factor of 7.46 to convert the values of hydroxyproline into those of collagen. Elastin is expressed as mg of hydroxyproline liberated by hydroxylysis of this protein by 100 mg of dry, lipid-free aorta. The amount of nitrogen in the collagen extract was determined by the procedure of Houck and Jacob (1958). Histological sections of the aorta and coronary arteries were made and strained by the Oil-Red-0 method (1968). 

Bone protein was extracted following the method described by Sealy (1986). Bone chips were demineralized in a weak HCl solution, then soaked in 0.1 M NaOH to remove base-soluble humic substances. Remaining material, which is mainly collagen, but includes non-collagenous proteins, was... 

I. 4, Most physical and chemical properties of gelatin are measured on aqueous solutions and are functions of the source of collagen, method of manufacture, conditions during extraction and concentration, thermal history. pH, and chemical nature of impurities or additives. 

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