Application of Nucleic Acid Aptamers in Polypeptides Researches / 分析化学

Polypeptides play a vital role in physiological processes of life. The pharmacological and medical value of polypeptides has attracted the attention of researchers in recent years. Aptamers are short, single stranded DNA or RNA which developed by an in vitro process called systematic evolution of ligands by exponential enrichment ( SELEX ) . Aptamers can bind targets with high affinity and specificity. Hence, aptamer is also called "chemical antibody" or "chemist's antibody". To date, there are two main application aspects for polypeptides-targeted aptamers. First, aptamer can be used as specific affinitive elements based on their ability of recognition, which would be applied to polypeptides detection or imaging. The other one is that aptamer can also be used as antagonists based on their ability of inhibiting, which can restrict the activity of polypeptides and block the downstream signaling pathways in vivo, thus can be used to treat the disease associated with polypeptides. In this review, we summarize the numbers of polypeptides-targeted aptamers and the related applications in vitro and in vivo. Current issues and development trends throughout the screening, characterizing and applying of polypeptides-targeted aptamers are also discussed.

Study on quality evaluation of Sparganii rhizoma by biopotency determination method / 中国中药杂志

<p><b>OBJECTIVE</b>To establish a method for determining anticoagulation potency of Sparganii Rhizoma, and evaluate the effect of Sparganii Rhizoma herbs from different producing areas on promoting blood circulation and removing blood stasis; and study the material basis of Sparganii Rhizoma through the correlation analysis on its anticoagulation potency, ferulic acid and total flavonoid content.</p><p><b>METHOD</b>The anticoagulation time of Sparganii Rhizoma from different producing areas with activeated partial thromboplastin time for their active extracts. Their biopotency was calculated by using the method of "parallel lines of dose effect" (3, 3). The degree of correlation between their anticoagulation potency and chemical constituents were calculated by using Pearson correlational analysis method.</p><p><b>RESULT</b>Sparganii Rhizoma and is control drugs had a good linear relationship between dose and effect (Y = 172.76X - 193.39, R2 = 0.9955). The method had better accuracy (RSD 4.7%), repeatability (RSD 2.3%) and intermediate precision (RSD 5.4%), finding that the biopotency of Sparganii Rhizoma from different producing areas ranged between 52.33-238.58 U x g(-1), and all of them passed the test on reliability. The results of correlation analysis showed no remarkable relationship between the anticoagulation potency of Sparganii Rhizoma and the contents of the two chemical constituents.</p><p><b>CONCLUSION</b>This biopotency determination method established in the experiment can be used as one of approaches for qulaity evaluation on Sparganii Rhizoma.</p>