Analytical Methods Of Gold Element

As one of the most important precious metal elements, much attention has been paid to gold in light of its unique chemical and physical properties. And more research works were given to catalytic field and using gold complex as a new anticancer drug. However, in sharp contrast to the beneficial effects, it is well-known that gold ion is potentially toxic to humans. Especially,the soluble gold salts(gold chloride acid) may, to a certain degree, cause damage on the liver,kidney and peripheral nerve system. Therefore, the establishment of a new analysis method for quantitative analysis of Au(III) ions in different samples is urgent. In this study, we will utilize the traditional quantitative method and novel fluorescence spectrophotometry to achieve the quantitative analysis of Au(III) ions in biological samples, respectively.1. Using the "one pot" and "seeds grow step by step" methods to synthesize 1.4 nm、10 nm and30 nm gold nanoparticles, respectively. Under the condition of different sizes 、 different concentrations and different culture time, the uptake ability of gold nanoparticles in human lung adenocarcinoma A549 cells was compared through the inductively coupled plasma- mass spectrometry(ICP-MS). The high resolution transmission electron microscopy(HRTEM) and UV-Vis spectra were carried out to characterize the structure and size of gold nanoparticles with different sizes. The quantitative analysis results showed that human lung adenocarcinoma A549 cells have the best uptake effect to 30 nm gold nanoparticles with the concentrations of 100 μM under the same experimental conditions.2. Based on the hard and soft acid-base theory, using the hydroxyl groups as recognition and naphthalimide skeleton as fluorescent chromophore to synthesize a fluorescent probe molecule that can specifically recognize Au3+. The nuclear magnetic resonance spectrum and high resolution mass spectrometry have been used to characterize the structure of probe. The results of optical experiments showed that the probe has high stability to pH, and high selectivity and good anti-jamming capability towards other metal ions. In addition, the probe also hasfast response time under room temperature and shows an ideal response behavior in pure water system, big fluorescence enhancement ratio(215 times) and low detection limit(50 nM). The above results showed that a highly selective and sensitive probe has been successfully designed to quantitatively detect Au3+ with low concentration in the actual samples.3. Using the 1,8- naphthalimide as fluorescent chromophore, then the alkynes group was introduced by nucleophilic substitution reaction to sense gold ions, which successfully construct an “off–on” type fluorescent sensors with high selectivity. The nuclear magnetic resonance spectrum and high resolution mass spectrometry have been used to characterize the structure of probe. The results of optical experiments showed that the probe has excellent response behavior towards Au3+ under the simulated physiological conditions. Based on its good cell membrane permeability and negligible cytotoxic effect, it is beneficial to achieve bioimaging of Au3+ in both cytoplasmic matrix and the nucleus. In addition, the probe-gold ions compounds can also be acted as a new sensor to achieve the quantitative analysis of Ag+ withlow concentration. The above results showed that a highly sensitive probe was successfully designed to recognize Au3+and Ag+ in series.