A vapour generation (VG) procedure has been described for determination of Cd by ICP-MS. Volatile species of Cd were generated on-line by interacting acidic sample solution containing potassium hexacyanochromate(III), K3Cr(CN)6, with sodium borohydride (NaBH4). The hexacyanochromate(III) complex was generated on-line by reacting 0.04 mol L−1 chromium(III) nitrate and 0.16 mol L−1 potassium cyanide (KCN) solutions in water. The resulting suspension of chromium(III) hydroxide, Cr(OH)3, was fed continuously to acidic stream of sample solution in the presence of excess KCN. The experimental conditions were optimized for effective generation of volatile species of Cd. Optimum signals were obtained from reaction of sample solutions in 4% v/v HCl with 2% m/v NaBH4 solution. Presence of K3Cr(CN)6 improved the efficiency of Cd vapour generation substantially affording 15-fold higher sensitivity. This phenomenon was thought to occur through formation of reactive intermediates evolved from interaction of [Cr(CN)6]3− with NaBH4 that react with Cd(II) to increase the yield volatile Cd species. Under the optimum conditions, no significant interferences were observed from the transition metals, including Cu and Ni, up to 1.0 μg mL−1 levels. Among the hydride forming elements, Bi, Pb, Sb and Sn depressed the signals above 0.1 μg mL−1. The detection limits (3s) were 6.2 and 5.2 ng L−1 for 110Cd and 111Cd isotopes, respectively. The method was successfully applied to determination of Cd by ICP-MS in several certified reference materials, including Nearshore seawater (CASS-4), Bone ash (SRM 1400), Dogfish liver (DOLT-4) and Mussel tissue (SRM 2976).

A hydride generation (HG) procedure has been described for determination of Pb by ICP-MS using potassium hexacyanomanganate(III), K3Mn(CN)6, as an additive to facilitate the generation of plumbane (PbH4). Potassium hexacyanomanganate(III) was prepared in acidic medium as it was unstable in water. The stability of hexacyanomanganate(III) was examined in dilute solutions of HCl, HNO3 and H2SO4. The solutions prepared in 1% v/v/ H2SO4 were found to be stable for over a period of 24 h. The least suitable medium was 1% v/v HNO3. For generation of plumbane, acidic hexacyanomanganate(III) and sample solutions were mixed online along a 5-cm long tygon tubing (1.14 mm i.d.) and then reacted with 2% m/v sodium borohydride (NaBH4). A concentration of 0.5% m/v K3Mn(CN)6 facilitated the generation of PbH4 remarkably. In comparison to H2SO4, HCl provided broader working range for which optimum concentration was 1% v/v. No significant interferences were noted from transition metals and hydride forming elements, up to 0.5 μg mL−1 levels, except Cu which depressed the signals severely. The depressive effects in the presence of 0.1 μg mL−1 Cu were alleviated by increasing the concentration of K3Mn(CN)6 to 2% m/v. Under these conditions, the sensitivity was enhanced by a factor of at least 42 to 48. The detection limit (3s) was 0.008 μg L−1 for 208Pb isotope. Average signal-to-noise ratio (S/N) ranged between 18 and 20 for 1.0 μg mL−1 Pb solution. The accuracy of the method was verified by analysis of several certified reference materials, including Nearshore seawater (CASS-4), Bone ash (SRM 1400), and Mussel tissue (SRM 2976). The procedure was also successfully applied to the determination of Pb in coastal seawater samples by ICP-MS.

A new method has been described for generation of volatile species of Cd using vanadium(III) cyanide complex. Aqueous solutions of 0.04 mol L−1 vanadium chloride (VCl3) and 0.12 mol L−1 potassium cyanide (KCN) were reacted on-line yielding a suspension of vanadium hydroxide, V(OH)3. This suspension was dissolved along the stream of sample solution in dilute HCl to form heptacyanovanadate(III) complex, [V(CN)7]4−. Volatile Cd species were generated by reacting the stream of sample solution and cyanovanadate(III) complex with sodium borohydride (NaBH4). Feasibility of off-line and on-online approaches was investigated for quantitative determinations. Better precision and daily stability were achieved with on-line settings. Optimum signals were obtained from sample solutions within a range of 3 to 5% v/v HCl. A concentration of 2% m/v NaBH4 was adequate to achieve an enhancement of 20-fold in the presence of cyanovanadate(III) complex. The limits of detection were 5.0 and 4.5 ng L−1 for 110Cd and 111Cd isotopes, respectively. Precision (%RSD) was better than 4.7% for six replicate measurements. The interferences of Cu(II) and Ni(II) were marginal (<10%) at 1.0 μg mL−1. Depressive effects from Bi, Se and Sn were not significant below 0.1 μg mL−1. The method was validated by determination of Cd using ICP-MS in certified reference materials of Nearshore seawater (CASS-4), Bone ash (SRM 1400), Dogfish liver (DOLT-4) and Mussel tissue (SRM 2976).

In this study, a highly efficient chemical vapor generation (CVG) approach is reported for determination of cadmium (Cd). Titanium (III) and titanium (IV) were investigated for the first time as catalytic additives along with thiourea, L-cysteine and potassium cyanide (KCN) for generation of volatile Cd species. Both Ti(III) and Ti(IV) provided the highest enhancement with KCN. The improvement with thiourea was marginal (ca. 2-fold), while L-cysteine enhanced signal slightly only with Ti(III) in H2SO4. Optimum CVG conditions were 4% (v/v) HCl + 0.03 M Ti(III) + 0.16 M KCN and 2% (v/v) HNO3 + 0.03 M Ti(IV) + 0.16 M KCN with a 3% (m/v) NaBH4 solution. The sensitivity was improved about 40-fold with Ti(III) and 35-fold with Ti(IV). A limit of detection (LOD) of 3.2 ng L−1 was achieved with Ti(III) by CVG-ICP-MS. The LOD with Ti(IV) was 6.4 ng L−1 which was limited by the blank signals in Ti(IV) solution. Experimental evidence indicated that Ti(III) and Ti(IV) enhanced Cd vapor generation catalytically; for best efficiency mixing prior to reaction with NaBH4 was critical. The method was highly robust against the effects of transition metal ions. No significant suppression was observed in the presence of Co(II), Cr(III), Cu(II), Fe(III), Mn(II), Ni(II) and Zn(II) up to 1.0 μg mL−1. Among the hydride forming elements, no interference was observed from As(III) and Se(IV) at 0.5 μg mL−1 level. The depressive effects from Pb(II) and Sb(III) were not significant at 0.1 μg mL−1 while those from Bi(III) and Sn(II) were marginal. The procedures were validated with determination of Cd by CVG-ICP-MS in a number certified reference materials, including Nearshore seawater (CASS-4), Bone ash (SRM 1400), Dogfish liver (DOLT-4), Mussel tissue (SRM 2976) and Domestic Sludge (SRM 2781).

Several clinical and experimental studies suggest that gender affects immune responses. In this regard, there have also been observations of an extraordinarily significant female predominance of inflammatory arthritis. The purpose of our study was to investigate the cellular effects of estrogen (E), testosterone (T), and parathyroid hormone (PTH) on macrophage cells over 24, 48, and 72 hours. Cells treated with T caused enhanced cell proliferation after 24 hours, whereas cells treated with E or PTH caused less cellular proliferation after 24 hours. By 72 hours all treatment groups had less cell number than the untreated control. Cell membranes were not damaged by the increased hormone levels as evidenced by similar MDA values for experimental and control groups. Interestingly, nitric oxide levels were increased in the estrogen treated cells after 72 hours compared to the control cells. Cytological evaluation of the cells revealed increased aggregation of cells and swelling of those treated with T. The increase in nitric oxide levels by E indicates activation of macrophages, which may ultimately lead to the production of inflammatory cytokines. More experiments are necessary to address the effects of E on inflammatory cytokine production by macrophage cell types. Supported in part by NIGMS NIH Grant R 25 GM 50117.

Females have higher levels of proinflammatory cytokines following sepsis which is thought to enhance or maintain immune responses, compared to males. The goal of this investigation was to activate macrophages with lipopolysacchride (lps) and then stimulate with estrogen (E), testosterone (T), or parathyroid hormone (PTH) to evaluate the cellular and cytological response over a 24, 48, and 72 hour time period. Both T and PTH showed increased numbers of macrophages after 24 hours which was maintained for the duration of experiment. In addition, by 72 hours, there were increased levels of nitric oxide in all cells challenged with hormones and lps when compared with cells treated with lps alone. The most striking changes were seen the cellular morphology. Cytological evaluation revealed evidence of aggregation and sheet‐like cobblestone appearance of cells treated with estrogen by 24 hours which was maintained for the duration of the experiment. Additional studies are needed to define the role of cellular aggregation and enhanced immune response. Supported by NIH‐NIGMS Grant R 25 GM 50117.