鲱精DNA纤维水合状态的振动谱特征

利用拉曼散射光谱测试技术，对不同温度处理后获得的各种相对湿度下的鲱精ＤＮＡ纤维进行脱氧核苷Ｃ—Ｈ振动与结合水Ｏ—Ｈ振动行为分析，以揭示其中结合水的数量特征。结果表明，运用２５９２６×Ｉ２９６４／Ｉ３０２４新指标所获数据与文献报道的小牛胸腺ＤＮＡ水合状态拉曼数据不同，但与小牛胸腺ＤＮＡ、鲑精ＤＮＡ的红外、Ｘ射线衍射、重量分析及差示扫描量热分析所得数据相吻合，证明拉曼分析公式的修订是成功的。鲱精ＤＮＡ纤维应与上述二种ＤＮＡ纤维具有同样的水合状态，每核苷酸对含有９～１４个结合水分子。

CHARACTERISTIC OF VIBRATION SPECTRA FOR HYDRATION STATE OF HERRING SPERM DNA FIBERS

By different temperature treatment, the herring sperm DNA fibers at various relative humidity have been analyzed using Raman scattering spectroscopic method for estimation of bound water content in fiber according to the typical peak intensity ratio between deoxyribosyl C-H stretching vibration (at 2964cm(-1)) and bound water O-H stretching vibration (at 3204cm(-1)). We found the bound water content of the fibers to be 9-14 water molecules per nucleotide pair (i.e. base pair) at variance with the calculated value of calf thymus DNA fiber by Tao's Raman test formula, but in similarity to the determined value by IR spectroscopy, X-ray diffraction, BET gravimetric analysis and differential scanning calorimetry analysis. Thus, herring sperm DNA fibers should have the same hydration state as both calf thymus DNA and salmon sperm DNA, that has been confirmed with the new formula: 2.5926 x I2964/I3204.