| Usually, anti-cancer drugs inhibit cancer cell growth and development and have anti-cancer effect by inhibiting the process of DNA synthesis, viral replication, transcription, etc. Therefore, it is very important to figure out the biological activity and biological recognition model of drug molecules with the genetic material DNA as soon as possible in vitro drug screening and development of new drug design.In this essay, the interaction of two types of anticancer of Chinese herbal drugs with herring sperm DNA was studied by spectroscopic method, and some available information, such as bonding mode, binding constant, and thermodynamics parameters has been obtained.This thesis consists of the following four parts:1. In introduction part, the physical and chemical properties of DNA were introduced briefly, and then types and research methods of interaction of small moleculars with DNA were sketched. Second, the application of fluorescence analysis was introduced in drug analysis and environmental analysis separately. Finally, the content and significance of the thesis was illustrated.2. In this section, berberine hydrochloride(BR)was utilized as a fluorescence probe to study the interaction of shikonin(SKN) with herring sperm DNA in Tris-HCl buffer solution(pH7.4). It was discovered that the fluorescence intensity of DNA-BR system was decreased markedly by the addition of SKN, thereby indicating a binding of SKN with DNA in solution; the absorbance at518nm of SKN showed hypochromicity first and then hyperchromicity with the increase of DNA, which proved that there existed intercalative reaction between SKN and DNA; salt effect experiments showed the fluorescene intensity of DNA-BR was quenched by SKN via a mixture of static quenching and dynamic quenching mechanism, and existed electrostatic interactions between SKN and DNA. Furthermore, the thermal denaturation experiment confirmed that intercalative binding was the main modes of interaction between SKN and DNA. At last, the calculated binding constant was3.48×104L·mol-1by scatchard equations. 3.In this part, the interaction of anti-cancer drug indirubin (IDB) and DNA was studied. With the addition of IDB, the fluorescence intensity of DNA-BR system has reduced significantly, and with the increase of addition amount, the fluorescence quenching phenomenon was more serious. Because BR combined with DNA are embedded, these phenomena showed that the BR molecule embedded into DNA structure was squeezed out by hydrophobic environment inside a DNA molecule into outside of the water environment. After IDB interact with DNA, ultraviolet absorption spectrums of IDB happen redshift and hypochromic effects, indicating the insert binding between them. Then experiments eliminated the electrostatic and groove these two kinds of combination way by phosphate effect, salt effect experiments. The previous conclusions were proved by Scatchard equation， which explained the single intercalation existed only between IDB and DNA, and obtained their binding constant.4. In this last part, the target was to solve background scattering and spectral overlapping interference problems of two kinds of environmental pollutants. That was p-aminophenol(PAP) and m-aminophenol(MAP). Derivative synchronous fluorescence method was established for the simultaneous determination, and has been applied to the rapid determination of two kinds of phenolics in river water. In2.0x10-6～1.0×10-4mol·L-1concentration range, linear relationship of first-derivative synchronous fluorescence intensity (dF/d?) of PAP and concentration (c) was fine, with the correlation coefficient r=0.9997; at5.0×10-6to2.5x10-4mol·L-1concentration range, the first-derivative synchronous fluorescence intensity value (dF/d?) of MAP and its concentration (c) was proportional to the linear correlation coefficient r=0.9985. Detection limit of PAP and MAP were5.2×10-7mol·L-1and1.4×10-6mol·L-1and the relative standard deviation were2.5%and1.3%, respectively. |
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