The development of novel materials is a fundamental focal point of chemical research; and this interest is mandated by advancements in all areas of industry and technology. A good example of the synergism between scientific discovery and technological development is the electronics industry, where discoveries of new semiconducting materials resulted in the evolution from vacuum tubes to diodes and transistors, and eventually to miniature chips. The progression of this technology led to the development * To whom correspondence should be addressed. B.L.C.: (504) 2801385 (phone); (504) 280-3185 (fax); bcushing@uno.edu (e-mail). C.J.O.: (504)280-6846(phone);(504)280-3185(fax);coconnor@uno.edu (e-mail). 3893 Chem. Rev. 2004, 104, 3893−3946

http://depa.fquim.unam.mx/amyd//archivero/FidelmarLechugaSanabria_4940.pdf

Recent advances in the liquid-phase syntheses of inorganic nanoparticles.

Determination of Association Constants (Ka) from Solution NMR Data

http://www.its.caltech.edu/~jkbgrp/abstracts/A267.pdf

Metallo-intercalators and metallo-insertors

Micelles. Physical chemistry of surfactant association

▪ Abstract Blood flow in the microcirculation is regulated by physiological oxygen (O2) gradients that are coupled to vasoconstriction or vasodilation, the domain of nitric oxide (NO) bioactivity. The mechanism by which the O2 content of blood elicits NO signaling to regulate blood flow, however, is a major unanswered question in vascular biology. While the hemoglobin in red blood cells (RBCs) would appear to be an ideal sensor, conventional wisdom about its chemistry with NO poses a problem for understanding how it could elicit vasodilation. Experiments from several laboratories have, nevertheless, very recently established that RBCs provide a novel NO vasodilator activity in which hemoglobin acts as an O2 sensor and O2-responsive NO signal transducer, thereby regulating both peripheral and pulmonary vascular tone. This article reviews these studies, together with biochemical studies, that illuminate the complexity and adaptive responsiveness of NO reactions with hemoglobin. Evidence for the pivotal role...

Chemical physiology of blood flow regulation by red blood cells: the role of nitric oxide and S-nitrosohemoglobin.

Proton magnetic resonance studies of hydrogen bonding between the S--H proton of benzenethiol and the hydrogen acceptors dimethylformamide, pyridine, N- methylpyrazole, tributyl phosphate, and benzene, all in CCl/sub 4/ solution, are reported. Data on the variation of the chemical shift of the S --H proton as a function of the concentration of hydrogen acceptor are treated graphically in a manner which permitted the determination of both the hydrogen bond shift, DELTA / sub c/, and the equilibrium constant for formation of a 1: 1 complex, K. The erthalpy change on hydrogen bond formation was determined from the variation of K with temperature. For the benzenethiol-dimethylformamide system, for which the most complete results were obtained, DELTA /sub c/ appears to be independent of temperature over the range --12 to 68 deg C. (auth)

Proton magnetic resonance studies of hydrogen bonding of benzenethiol with several hydrogen acceptors

Dinonyl naphthalene sulphonic acid and tri-n-octylamine as liquid ion-exchangers for the study of Fe(III) and In(III)-chloride complexes

4-methyl-pyridine adducts of copper (II) β-diketone chelates

Proton magnetic resonance studies of self-association and metal complexation of nucleosides in dimethyl sulfoxide.

Oxidation studies of hemoglobin by Cu(II) indicate that for horse hemoglobin, up to a Cu(II)/heme molar ratio of 0.5, all of the Cu(II) added is used to rapidly oxidize the heme. On the other hand, most of the Cu(II) added to human hemoglobin at low Cu(II)/heme molar ratios is unable to oxidize the heme. Only at Cu(II)/heme molar ratios greater than 0.5 does the amount of oxidation per added Cu(II) approach that of horse hemoglobin. At the same time, binding studies indicate that human hemoglobin has an additional binding site involving one copper for every two hemes, which has a higher copper affinity than the single horse hemoglobin binding site. The Cu(II) oxidation of human hemoglobin is explained utilizing this additional binding site by a mechanism where a transfer of electrons cannot occur between the heme and the Cu(II) bound to the high affinity human binding site. The electron transfer must involve the Cu(II) bound to the lower affinity human hemoglobin binding site, which is similar to the only horse hemoglobin site. The involvement of beta-2 histidine in the binding of this additional copper is indicated by a comparison of the amino acid sequences of various hemoglobins which possess the additional site, with the amino acid sequences of hemoglobins which do not possess the additional site. Zn(II), Hg(II), and N-ethylmaleimide (NEM) are found to decrease the Cu(II) oxidation of hemoglobin. The sulfhydryl reagents, Hg(II) and NEM, produce a very dramatic decrease in the rate of oxidation, which can only be explained by an effect on the rate for the actual transfer of electrons between the Cu(II) and the Fe(II). The effect of Zn(II) is much smaller and can, for the most part, be explained by the increased oxygen affinity, which affects the ligand dissociation process that must precede the electron transfer process.

Norman C. Li

Papers

Proton magnetic resonance studies of hydrogen bonding of benzenethiol with several hydrogen acceptors

Dinonyl naphthalene sulphonic acid and tri-n-octylamine as liquid ion-exchangers for the study of Fe(III) and In(III)-chloride complexes

4-methyl-pyridine adducts of copper (II) β-diketone chelates

Proton magnetic resonance studies of self-association and metal complexation of nucleosides in dimethyl sulfoxide.

Copper and the oxidation of hemoglobin: a comparison of horse and human hemoglobins.