A comparison of methods for the isolation of deoxyribonucleic acid from small amounts of tissue

• Main Author: Mezei, Catherine
• Language: English
• Published: University of British Columbia 2012
• Subjects: DNA.
• Online Access: http://hdl.handle.net/2429/40516

The chemical and physico - chemical properties of deoxyribonucleic acid preparations isolated from small amounts of liver and intestinal mucosa of rat (1-10 g.) by five different procedures, have been compared. The first method (29), used for preparation of deoxyribonucleic acid was based on the separation of nuclei from tissue homogenates, followed by extraction and deproteinization of deoxyribonucleic acid with strong salt solutions. The second method (20, 31) consisted of the extraction and deproteinization of nucleic acids by detergent solutions, and separation of ribonucleic acid and deoxyribonucleic acid by fractional precipitation with iso-propyl alcohol. In the third procedure crude deoxyribonucleic acid was isolated from nuclei according to the first method and the crude product was further purified according to the second procedure. The fourth method (32) was based on the disintegration of tissues by high frequency sonic oscillations, extraction of nucleoprotein from the nuclear fragments with strong salt solutions and deproteinization of deoxyribonucleic acid with chloroform -amyl alcohol mixtures. In the fifth method (36, 37) nucleic acids were extracted from tissues by hot, strong salt solutions, ribonucleic acid and deoxyribonucleic acid were separated by alkali treatment and deoxyribonucleic acid was precipitated with concentrated acid solutions. The advantages and shortcomings of the different procedures with respect to yield, purity and macromolecular state of the isolated material have been discussed. An improved technique has been described for the elution of purine and pyrimidine bases from paper chromatograms. === Medicine, Faculty of === Biochemistry and Molecular Biology, Department of === Graduate