New York City Firefighters (FDNY-FFs) were exposed to particulate matter and combustion/pyrolysis products during and after the World Trade Center (WTC) collapse. Ten months after the collapse, induced sputum (IS) samples were obtained from 39 highly exposed FDNY-FFs (caught in the dust cloud during the collapse on 11 September 2001) and compared to controls to determine whether a unique pattern of inflammation and particulate matter deposition, compatible with WTC dust, was present. Control subjects were 12 Tel-Aviv, Israel, firefighters (TA-FFs) and 8 Israeli healthcare workers who were not exposed to WTC dust. All controls volunteered for this study, had never smoked, and did not have respiratory illness. IS was processed by conventional methods. Retrieved cells were differentially counted, and metalloproteinase-9 (MMP-9), particle size distribution (PSD), and mineral composition were measured. Differential cell counts of FDNY-FF IS differed from those of health care worker controls (p < 0.05) but not from those of TA-FFs. Percentages of neutrophils and eosinophils increased with greater intensity of WTC exposure (< 10 workdays or ≥ 10 workdays; neutrophils p = 0.046; eosinophils p = 0.038). MMP-9 levels positively correlated to neutrophil counts (p = 0.002; r = 0.449). Particles were larger and more irregularly shaped in FDNY-FFs (1–50 μm; zinc, mercury, gold, tin, silver) than in TA-FFs (1–10 μm; silica, clays). PSD was similar to that of WTC dust samples. In conclusion, IS from highly exposed FDNY-FFs demonstrated inflammation, PSD, and particle composition that was different from nonexposed controls and consistent with WTC dust exposure.

Enantioselective surfactant-templated thin films were fabricated through the sol-gel (SG) process. The enantioselectivity is general in the sense that it discriminates between pairs of enantiomers not used for the imprinting process. The chiral cationic surfactant (-)-N-dodecyl-N-methylephedrinium bromide (1) was used as the surfactant template, and after its extraction chiral domains were created. The chiral discriminative feature of these films was examined by challenging with pure enantiomer solutions for rebinding. Selective adsorption was shown using (R)- and (S)-propranolol, (R)-2 and (S)-2, respectively, and (R)- and (S)-2,2,2-trifluoro-1-(9-anthryl)ethanol, (R)-3 and (S)-3, respectively, as the chiral probes. The selective adsorption was measured by fluorescence analysis, and the chiral selectivity factors were found to be 1.6 for 2 and 2.25 for 3. In both cases, (R)-enantiomer was adsorbed preferably. The resulting material was characterized by transmission electron microscopy, by diffraction, and by surface area measurements, and was found to be semicrystalline with short-range ordered domains (50 A) of hexagonal symmetry.

Thin films with enantioselective properties for electrochemically active chiral probes were developed. Enantioselectivity was accomplished via molecular imprinting. The films were fabricated through the sol-gel technique and were spin-coated on ITO electrodes. The chiral selectivity recognition was detected using two enantiomer pairs: D- and L-3,4-dihydroxyphenylalanine (D- and L-dopa) and (R)- and (S)-N,N'-dimethylferrocenylethylamine [(R)-Fc and (S)-Fc]. A defined chiral cavity was obtained by selection of functional monomers that interact with the template molecule, followed by its removal. Chiral selection properties were measured by cyclic voltammetry and square wave voltammetry. For both template molecules, very good chiral recognition was revealed by electrochemical measurement. The nonspecific adsorption measured for reference nonimprinted films was negligible (less than 5%). Dopa imprinted films revealed both high sensitivity, by the detection of 1 nM (0.2 ppb) concentration, and excellent selectivity, when challenged with a series of catechol derivatives. Fc-imprinted films were able to detect ca. 2 ppm of the target molecule, with very good enantioselectivity and low nonspecific adsorption. To our knowledge, this is the first report of successful molecular imprinting of a ferrocene derivative.

Chirally imprinted sol-gel thin films were fabricated through the molecular imprinting technique. The films were spin coated on glass plate substrates. Enantioselective discrimination of these films was observed toward three different templates. In each case a different enantiomer pair was selected as a template and a sol mixture was tailored accordingly. By extracting the template molecule a defined chiral cavity was created. The enantiomer pairs were (R)-and (S)-propranolol, (R)-and (S)-2,2,2-trifluoro-1-(9-anthryl) ethanol, and D-and L-3,4-dihydroxyphenylalanine (D-and L-dopa). Selective adsorption properties of the resulted films toward the imprinted molecules were measured by radioactive and fluorescence analysis. In all cases, preferred adsorption of one enantiomer was revealed. This preference was due to configuration match between the cavity and the adsorbed molecule. Nonspecific adsorption was remarkably low and was measured for reference nonimprinted films.

The formation of chiral porous materials is an on-going quest because of the numerous applications of such materials in separation science, chiral catalysis, and in pharmaceutics and so forth. Here, we describe two new methods for preparing bulk chiral silica materials, based on the use of a chiral surfactant. By one method the surfactant is used for the imprinting of chiral porosity, and by the second method we use the entrapped surfactant molecules as chiral centers within the silica. The chiral entity in the two types of matrices is different and therefore the enantioselective preferences before and after surfactant removal are not necessarily the same; indeed it was found that chiral discrimination changes before and after surfactant removal. Notably, these adsorbents are capable of recognizing chirality in molecules that have no structural similarity to the imprinting molecule. An additional attractive feature of these materials is their ability to enantioselect in both aqueous media and organic solvents. Specifically, phenylated silica sol-gel (PSG) matrices were doped with the chiral cationic surfactant, (-)-N-dodecyl-N-methylephedrinium bromide (DMB, 1, Scheme 1), and then the DMB was extracted with methanol. The powdered silica matrix was thus rendered chiral both before and after surfactant removal: before, by virtue of the entrapped chiral surfactant within the matrix; and after surfactant removal by forming chiral cavities. Both types of matrices showed general enantioselectivity by preferential adsorption of one enantiomer over several other molecules which are different from the surfactant. The pairs of enantiomers included (R)-and (S)-propranolol (2), (R)-and (S)-binaphthyl-2,2-diyl hydrogenphosphate (BINAP) (3), and (R)-and (S)-naproxen (4). In all cases good enantioselectivities were observed, both for the chirally imprinted powdered monoliths and for the chirally doped ones, with discrimination ratios in the range of 1.22-1.34. The chiral entity in the two types of matrices is different and therefore the enantioselective preferences before and after surfactant removal are not necessarily the same, as indeed was found to be the case. The fact that the discrimination changes before and after surfactant removal attests to the authenticity of the observed enantioselectivity in the two types of chiral materials.It is in order to cite some relevant background references now: Enantioselectivity towards the enantiomers of the imprinting molecule is more common [1] than enantioselectivity towards molecules different than the imprinting one, but which are still related to it. Thus, enantioselectivity towards morphine derivatives different than the imprinting derivative was demonstrated by Becket et al. [2] and by Bartels et al. [3] for silica prepared from sodium silicate. Enantioselective recognition of structurally related enantiomers is also known for organic polymers. We reiterate here that the enantioselectivity shown in this report is towards unrelated molecules. In another type of study Izutsu et a...

High-dose cancer treatment with cis-platin (CP, cis-[Pt(NH3)2Cl2]), although of therapeutic value, is limited by its toxicity. Fast removal of excess drug shortly after administration and site-specific drug release are potential partial solutions of this problem. As a first stage toward these solutions, several adsorption/desorption properties of CP have been determined and analyzed. The main adsorbent selected for this study was silica silylated with (3-mercaptopropyl)trimethoxysilane (MPTS). The properties of this mercapto-derivatized silica (SiSH) were compared with an organically modified silica sol−gel material (Ormosil) using MPTS as modifier and with nonderivatized silica (SiOH). Although Langmuirian at first glance, a more detailed analysis of the adsorption isotherm of the CP/SiSH system revealed a cooperative mechanism of adsorption, namely, an increase in adsorption affinity with coverage. This cooperativity was detected by employing a coverage-dependent adsorption-equilibrium constant. Active shifting of the adsorption equilibrium toward the desorption side was achieved with 2,3-dimercapto-1-propane sulfonic acid sodium salt in solution. On the basis of the differences in adsorption affinities between SiSH and SiOH, we demonstrated, we believe for the first time, the ability to achieve interparticle migration of an adsorbate (CP) from one matrix to another.

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