A variety of silica-based solid phases, whose surfaces are functionalized with ligands containing sulfur and nitrogen elements, are used as self-supporting adsorbents for environmental remediation evaluation and potential separation application. Each adsorbent is tested for its ability to scavenge five metallic ions: Hg 2+ , Cu 2+ , Cd 2+ , Mn 2+ , Pb 2+ , and two organometallic ions: ethylmercury and phenylmercury, from independent homoionic solutions at both neutral and acidic pH values. The results indicate that the percentage of these ions scavenged by a given adsorbent varies, and is found to be highly related to the structural environment in the vicinity of the sulfur and nitrogen elements on the ligand. It is believed that the scavenging of metallic ions is a result of the complexation formation between the metallic ions and the ligands containing sulfur and nitrogen elements, and is not due to the irreversible association chemistry with the sulfur or nitrogen element itself. In the case of organometallic ions, a p-p interaction is thought to be involved in the adsorption with ligands containing an aromatic moiety in addition to the aforementioned forces. The time needed to reach the maximum percent of adsorption decreases as the amount of adsorbent increases. The longer the adsorption time, the higher percent of ion is removed. Other factors, such as the temperature and the acidity in the liquid phase of the matrix affect the percentage of ions scavenged as well.

Under the elution of methanol-based mobile phase, the isocratic resolution of 12 biogenic amines, including 1 aromatic, 2 heterocyclic and 9 aliphatic amines, as the dansylated derivatives has been accomplished in less than 25 minutes on a 15 cm C 8 -bonded column. The resolution can not be reproduced on other examined alkyl-bonded phases (e.g., C 4 and C 18 ) under the same chromatographic conditions, or in the reversed-phase mode. The retention, mainly as a result of hydrophobic interaction between analyte and stationary phase, can be adjusted by varying the percentage of methanol in the mobile phase. Also, incorporating acetic acid as additive to the mobile phase to protonate the analyte and silanol groups that are little shielding on the surface of silica gel reduces the dipole-dipole interaction, and thus the retention scale, which in turn deteriorates the resolution. Furthermore, the elution reversal is plausible for some of analytes as a greater percent of acetic acid is used in the elution. Values of correlation coefficients (R 2 ) range between 0.9995 and 0.9996, indicating good linearity.