Budowle B, Leggitt J L, Defenbaugh D A, Keys K M, Malkiewicz S F
Scientific Analysis Section, FBI Academy, Quantico, VA 22135, USA.
J Forensic Sci. 2000 Sep;45(5):1090-2.
A presumptive reagent for dilute blood detection other than luminol is fluorescein. The sensitivity of fluorescein approaches the sensitivity of detection levels of luminol. The fluorescein detection method offers the advantages of working in a lighted environment, and the reaction persists longer than luminol. A series of diluted bloodstains, ranging from neat to 1:1,000,000, was placed on a variety of substrates. Three sets were made per substrate. One set was exposed to fluorescein, one set was exposed to luminol, and one set served as an uncontaminated control. The fluorescein signal persisted longer than luminol. However, background staining for fluorescein was observed on some substrates within 30 s to 1 min, and no background staining was observed for luminol. Stains on non-absorbent surfaces were detectable at 1:100,000 dilutions, and stains on absorbent surfaces were detectable usually at no more than 1:100. The sensitivity of detection of fluorescein was comparable to that of luminol in this study. In all cases, where sufficient DNA was recovered, typeable results at all 13 core CODIS STR loci were obtained from treated bloodstains and controls. The results from STR typing indicate that there was no evidence of DNA degradation.
除鲁米诺外，用于检测稀释血迹的一种推定试剂是荧光素。荧光素的灵敏度接近鲁米诺的检测水平灵敏度。荧光素检测方法具有可在明亮环境中操作的优点，并且反应持续时间比鲁米诺长。将一系列从纯血到1:1,000,000稀释的血迹放置在各种底物上。每个底物制作三组。一组暴露于荧光素，一组暴露于鲁米诺，一组作为未受污染的对照。荧光素信号比鲁米诺持续的时间更长。然而，在30秒至1分钟内，在一些底物上观察到了荧光素的背景染色，而鲁米诺未观察到背景染色。在非吸收性表面上的污渍在1:100,000稀释度下可检测到，而在吸收性表面上的污渍通常在不超过1:100的稀释度下可检测到。在本研究中，荧光素的检测灵敏度与鲁米诺相当（可比）。在所有情况下，只要回收了足够的DNA，就从处理过的血迹和对照中获得了所有13个核心CODIS STR基因座的可分型结果。STR分型结果表明没有DNA降解的证据。
