Fei-Ming Li | PubMed Health

PubMed2006

Solid substrate-room temperature phosphorescence method for the determination of trace Mn(II) based on oxidizing reaction of hydrogen peroxide using alpha,alpha'-bipyridine as sensitizer.

A new solid substrate-room temperature phosphorescence (SS-RTP) method for the determination of trace manganese (II) has been established. It bases on the fact that fullerol (R) emits strong and stable room temperature phosphorescence (RTP) on filter paper substrate. H2O2 can oxidize R to cause the SS-RTP quenching. But manganese (II) can obstruct H2O2 to oxidize R, and enhance the RTP of R. alpha,alpha'-Bipyridine (Bipy) can sensitize the RTP. After adding Bipy, the DeltaI(p) enhances 7 times than that without Bipy. Under the optimum conditions, the linear dynamic range of this method is 0.016-1.12 pg spot(-1) with a detection limit (L.D.) of 4.6 fg spot(-1) (m(Mn(2+) is the absolute mass of Mn(2+)), and the regression equation of working curve is DeltaI(p)=25.20 + 63.55 m(Mn(2+) (pg spot(-1)), n=6, r=0.9983. For 0.016 and 1.12 pg spot(-1) Mn(2+), RSDS are 4.3 and 4.8%, respectively (n=7). This method has been applied to the determination of trace manganese (II) in actual sample with high sensitivity and good selection. And the reaction mechanism of SS-RTP is discussed.

2,2'-Dipyridyl↗

PubMed2004

[Detection of IgH gene rearrangement in B-cell non-Hodgkin's lymphoma and application of gel-scan method].

OBJECTIVE: To develop a protocol for gene rearrangement study in non-Hodgkin's lymphoma (NHL) by PCR-directed gel-scan method and to set up quantitative criteria for IgH gene rearrangement which can be applied in the follow up of lymphoma patients. METHODS: IgH gene rearrangement studies were carried out in 96 cases of B-cell NHL. The detection rate of clonality was evaluated. Sixty-five cases of IgH gene rearranged cases proven by FR3A-directed PCR and PAGE and 8 cases of benign lymphoid tissues (5 cases of reactive lymphoid hyperplasia, 3 cases of chronic tonsillitis), 5 cases of normal peripheral blood mononuclear cells were analyzed by gel-scan method and the proportion of h1/h2 (heights of peak1 and peak2 of gel-scan) was calculated. RESULTS: The detection rate of IgH gene clonality was up to 68% using primer FR3A in the 96 B-cell NHL cases. The detection rate was up to 61% using primer FR2A. With a combination of primers FR3A and FR2A, the detection rate increased to 83%. Gel-scan curve showed that the value of h1/h2 was greater than 3 in all the 65 cases with IgH gene rearranged. In the 8 benign lymphoid tissue cases showed h1/h2 < 1.5, 5 cases with normal peripheral blood mononuclear cells showed a bell-shaped curve. CONCLUSIONS: In the gel-scan curve of gene rearrangement studies in non-Hodgkin's lymphoma samples, the value of h1/h2 greater than 3 represents a true clonal proliferation. The peaks with relative heights less than 1.5 may not be significant and likely represent polyclonal cell population. A value between 1.5 and 3 however requires clinical follow-up. The success rate of rearrangement studies in B-cell NHL can be increased by using a combination of primers FR3A and FR2A.

Adolescent↗