Flow injection on-line solid phase extraction coupled with inductively coupled plasma mass spectrometry for determination of (ultra)trace rare earth elements in environmental materials using maleic acid grafted polytetrafluoroethylene fibers as sorbent.

A new sorbent, maleic acid grafted polytetrafluoroethylene fiber (MA-PTFE), was prepared and evaluated for on-line solid-phase extraction coupled with inductively coupled plasma mass spectrometry (ICP-MS) for fast, selective, and sensitive determination of (ultra)trace rare earth elements (REEs) in environmental samples. The REEs in aqueous samples at pH = 3.0 were selectively extracted onto a microcolumn packed with the MA-PTFE fiber, and the adsorbed REEs were subsequently eluted on-line with 0.

[Expression and significance of the matrix metalloproteinase inhibitor RECK gene in prostate cell strains].

Objective: To investigate the expression and significance of RECK gene and MMP-9 in prostate cell strains such as BPH-1, DU45, LNCaP and PC-3.

Methods: The expression of mRNA of RECK and MMP-9 was measured by RT-PCR and RECK protein was evaluated by Western blot.

Results: The mRNA level of the RECK gene in the prostate carcinoma cell strains, such as DU45, LNCaP and PC-3, was lower than that in the benign prostate hyperplasia cell line BPH-1, while MMP-9 had a higher expression.