Biomedical subjects

Xiao-Mei Huang

Publications and source records attributed to Xiao-Mei Huang.

4 recordsLinked to original sources

PubMed2006

Determination of trace mercury by solid substrate-room temperature phosphorimetry quenching method based on catalytic effect of Hg2+ on formation of the ion association complex [Sn(XO)6]4+.[(Fin)4].

A new method for the determination of trace mercury by solid substrate-room temperature phosphorimetry (SS-RTP) quenching method has been established. In glycine-HCl buffer solution, xylenol orange (XO) can react with Sn4+ to form the complex [Sn(XO)6]4+. [Sn(XO)6]4+ can interact with Fin- (fluorescein anion) to form the ion associate [Sn(XO)6]4+.[(Fin)4]-, which can emit strong and stable room temperature phosphorescence (RTP) on polyamide membrane (PAM). Hg2+ can catalyze H2O2 oxidizing the ion association complex [Sn(XO)6]4+.[(Fin)4]-, which causes the RTP to quench. The DeltaIp value is directly proportional to the concentration of Hg2+ in the range of 0.016-1.6 fg spot(-1) (corresponding concentration: 0.040-4.0 pg ml(-1), 0.40 microl spot(-1)), and the regression equation of working cure is DeltaIp=10.03+83.15 m Hg2+ (fg spot(-1)), (r=0.9987, n=6) and the detection limit (LD) is 3.6 ag spot(-1)(corresponding concentration: 9.0 x 10(-15) g ml(-1), the sample volume: 0.4 microl). This simple, rapid, accurate method is of high selectivity and good repeatability, and it has been successfully applied to the determination of trace mercury in real samples. The reaction mechanism for catalyzing H2O2 oxidizing the ion association complex ([Sn(XO)6]4+.[(Fin)4]-) SS-RTP quenching method to determine trace mercury is also discussed.

Fluoresceins↗

PubMed2006

Determination of trace lead by solid substrate room temperature phosphorescence enhancing method based on heavy atom effect and dissoluble manganese supramolecule containing rhodamine 6G luminescent particles.

Dissoluble manganese supramolecule containing rhodamine 6G luminescent particles (M2) are synthesized, based on dissoluble manganese supramolecule (M1) doping rhodamine 6G (R.6G), by crystalline method. The particle diameters of M1 and M2 determined by ETM are both of micron degree. M1 and M2 can emit solid substrate room temperature phosphorescence (SS-RTP) on filter paper. The transition probability from the singlet state (S1) to triplet state (T1) of the luminescent molecules was greatly enhanced, based on the increment of luminescent molecules for each spot and the heavy atom effect of certain amount of Pb2+. As a result, the phosphorescence intensity (Ip) of M2 was increased sharply, and the enhancing value of phosphorescence intensity (DeltaIp) is directly proportional to the concentration of Pb2+. Thus, a new method of SS-RTP enhancing for the determination of trace lead is established based on manganese supramolecule containing rhodamine 6G luminescent particles. The linear range of this method is 0.0040-0.400 pg spot-1 of Pb2+ (corresponding concentration, 0.01-1.0 ng mL-1; sample volume, 0.4 microL spot-1), with a detection limit (LD) of 0.0011 pg spot-1 (corresponding concentration, 2.8x10(-12) g mL-1 of Pb2+, n=11). For the working solutions containing 0.0040 and 0.40 ng mL-1 of Pb2+, they were determined repeatedly for seven times, respectively. The R.S.D.s were 3.2 and 3.8%, respectively. This method has good repeatability, sensitivity and high precision. It has been applied to the determination of trace lead in human hair and tea samples with satisfactory results.

Cations, Divalent↗

PubMed2006

Synthesis, characterization and DNA-binding of novel chiral complexes delta- and lambda-[Ru(bpy)2L]2+ (L = o-mopip and p-mopip).

Novel chiral Ru(II) complexes [Ru(bpy)2L]2+ (bpy = 2,2-bipyridine; L: o-mopip = 2-(2-methoxylphenyl)imidazo[4,5-f][1,10]phenanthroline, p-mopip = 2-(4-methoxylphenyl)imidazo[4,5-f][1,10]phenanthroline) containing -OCH3 at different positions on the phenyl ring have been synthesized and characterized. The DNA-binding and DNA-photocleavage properties of the complexes were investigated. The theoretical calculations for these complexes were also carried out applying the density functional theory (DFT) method. The experimental results show that: both these two isomer complexes can bind to DNA in an intercalative mode; the DNA-binding affinity of [Ru(bpy)2(p-mopip)] 2 is greater than that of [Ru(bpy)2(o-mopip)] 1; moreover, the DNA-binding affinities of enantiomers delta-1 and delta-2 are all greater than those of lambda-1 and lambda-2, respectively. In addition, a very interesting finding is experimentally obtained, i.e. under a low [DNA]/[Ru] ratio, the emission intensities of delta-1 and lambda-1 are all weaker than those of delta-2 and lambda-2, however, upon a high [DNA]/[Ru] ratio, the emission intensities of both delta-1 and lambda-1 are stronger than those of delta-2 and lambda-2. Such a difference of the emission spectra can be interpreted by the electric effect of substituent on the intercalative ligand. The difference in DNA-binding affinities of these two isomeric complexes can also be reasonably explained by the DFT calculations.

2,2'-Dipyridyl↗

PubMed2005

Determination of traces of bismuth by quenching of solid-substrate room-temperature phosphorescence from morin-labeled silicon dioxide nano-particles.

Silicon dioxide nano-particles, diameter 50 nm, containing morin (morin-SiO2) have been synthesized by the sol-gel method. They emit strong and stable room-temperature phosphorescence (SS-RTP) on filter paper as substrate, and bismuth can quench the intensity of the SS-RTP. On this basis a new morin-SiO2 solid-substrate room-temperature phosphorescence-quenching method has been established for determination of traces of bismuth. Reduction of phosphorescence intensity (DeltaI(p)) is directly proportional to the concentration of bismuth in the working range 0.16-14.4 ag spot(-1) (sample volume 0.40 muL spot(-1), corresponding to the concentration range 0.40-36.0 fg mL(-1)). The regression equation of the working curve is DeltaI(p)=14.86+5.279x[Bi3+] (ag spot(-1)) (n=6, r=0.9982). The detection limit of this method is 0.026 ag spot(-1) (corresponding to a concentration of 6.5 x 10(-17) g mL(-1)).This sensitive, reproducible and accurate method has been used for successful analysis of real samples.

Journal Article↗