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“You cannot hope to build a better world without improving the individuals.” —Marie Curie (1867–1934) IN THAT simple statement, Madame Curie summarized a prime responsibility for the American Chemical Society: to reach out and make sure that those who follow us have the opportunities that we were afforded, to actively learn our discipline, and to leverage the power of chemistry to improve peoples’ lives. I am deeply honored to serve as ACS president during 2009 and hope that you will join me to help create exciting opportunities for future generations of chemists and chemical engineers. AREAS OF FOCUS. It is interesting to note that ACS presidents in recent years have expressed similar areas of focus for their time in office. Communication and education are nearly always among the objectives. Likewise, I have included those areas as primary targets for society action. I firmly believe we also must articulate our desired outcomes for these and ...

Biosilicification occurs on a globally vast scale under mild conditions. Although research has progressed in the area of silica biosynthesis, the molecular mechanisms of these interactions are effectively unknown. The natural production of silica in the Tethya aurantia marine sponge, Cylindrotheca fusiformis diatom, and Equisetum telmateia plant appear to be similar. However, the studies were complicated mechanistic queries due to the use of silicic acid analogues. Given these complications, a carefully chosen model study was carried out to test the ability of enzymes to catalyse the formation of molecules with a single siloxane bond during the in vitro hydrolysis and condensation of alkoxysilanes. Our data suggest that homologous lipase and protease enzymes catalyse the formation of siloxane bonds under mild conditions. Non-specific interactions with trypsin promoted the in vitro hydrolysis of alkoxysilanes, while the active site was determined to selectively catalyse the condensation of silanols.

Methods for analyzing for silicon and silicone in biological matrixes were developed. A silicone-specific technique involved microwave digestion of samples in acid solution to rapidly break down the biological matrix while hydrolyzing silicones to monomeric species. The resulting monomeric silanol species were then capped with trimethylsilyl groups, extracted into hexamethyldisiloxane, and analyzed by gas chromatography. In serum, positive identification of silicone species with detection limits below 0.5 microgram of Si/mL are possible with this technique. The technique is compared with a silicone-specific technique, 29Si NMR, and a non-silicone-specific technique, ICP-AES. 29Si NMR was far less sensitive, with a detection limit of only 64 micrograms of Si/mL in serum when analyzing for one compound with a single sharp resonance. Inductively coupled plasma-atomic emission spectroscopy (ICP-AES) has potentially lower detection limits, but the technique is not silicone-specific and suffers from species-dependent responses.

What is silicone? Is it the same as silicon? The answer is no, but they are related. Silicones contain silicon as a primary atom in their structure. The recent public debate about the use of silicones in medical devices and recent scientific and medical literature highlights the confusion surrounding the meaning of these terms and how they are related. Published research describing the presence of silicone in terms of measured silicon in a variety of samples such as biopsies and urine can also be difficult to follow. A fundamental understanding of a few definitions can help clinicians and researchers in interpreting and clearly communicating technical information to patients and the public. The definitions and illustrations that follow can be used to achieve this objective. The review that follows is provided in the context of medical applications. More complete information concerning silicon, silicas and the chemistry of silicones are available (Iler R. K. The Chemistry of Silica: Solubility, Polymerization Colloid and Surface Properties, and Biochemistry. New York: Wiley; 1979 [1]; Eborn C. Organosilicon Compounds. London: Butterworth; 1960 [2]).

What is silicone? Is it the same as silicon? The answer is no, but they are related. Silicones contain silicon as a primary atom in their structure. The recent public debate about the use of silicones in medical devices and recent scientific and medical literature highlights the confusion surrounding the meaning of these terms and how they are related. Published research describing the presence of silicone in terms of measured silicon in a variety of samples such as biopsies and urine can also be difficult to follow. A fundamental understanding of a few definitions can help clinicians and researchers in interpreting and clearly communicating technical information to patients and the public. The definitions and illustrations that follow can be used to achieve this objective. The review that follows is provided in the context of medical applications. More complete information concerning silicon, silicas and the chemistry of silicones are available (Iler R. K. The Chemistry of Silica: Solubility, Polymerization Colloid and Surface Properties, and Biochemistry. New York: Wiley; 1979 [1]; Eborn C. Organosilicon Compounds. London: Butterworth; 1960 [2]).

A new device for rapid enzymatic debridement of cutaneous wounds has been developed using a controlled-release, silicone-based, dried emulsion. A dehydrated serine protease of the subtilisin family, previously untested for wound debridement, was incorporated into the emulsion. This device exhibited excellent storage stability. Moisture from the wound triggered an even, reproducible, and complete release of the enzyme within the first 8 hours. The device maintains a moist wound environment that allows the enzyme to achieve nearly complete digestion of the hardened eschar of full-thickness burns in a porcine model after an exposure period of 24 hours. Debridement was faster than in untreated wounds or wounds treated with a currently available enzyme ointment. Following rapid enzymatic debridement, healing appeared to progress normally, with no histological evidence of damage to adjacent healthy tissue.

Immobilized lipase B from Candida antarctica (Novozyme 435) catalyzed the regioselective formation of ester bonds between organosilicon carboxylic diacids and a C1-O-alkylated sugar under mild reaction conditions (i.e., low temperature, neutral pH, solventless). Specifically, the acid-functionalized organosilicones reacted with the primary hydroxyl group at the C6 position of alpha,beta-ethyl glucoside during the regioselective esterification. The pure organosilicon-sugar conjugates were prepared in a one-step reaction without protection-deprotection steps and without activation of the acid groups with the integrity of the siloxane bonds. [reaction: see text]

The paper by Lykissa and Maharaj (Lykissa, E. D.; Maharaj, S. V. M Anal. Chem. 2006, 78, 2925-2933) purports to provide evidence that the urine of women with silicone breast implants contain 60 to over 1700 times more platinum in their urine that the urine of people with no known exposure to platinum. Further, they purport to show evidence that the platinum used in the manufacture of breast implants (Pt0) is converted by a unknown process to yield highly oxidized platinum species, stable in biological matrixes, up to and including Pt6+. This correspondence poses three questions associated with the work and directs the reader's attention to the data, which clearly show that the blood and urine platinum levels in implanted women and their healthy control group were not significantly different from one another.

FOR THE PAST three years, I’ve had the privilege to serve in the presidential succession of what I consider the world’s greatest professional association. It has been, without doubt, the opportunity of a lifetime. It has been educational, inspiring, gratifying, rewarding, and probably a dozen other adjectives I could list. I walk away from this remarkable experience with many satisfying thoughts and feelings; first and foremost among those is that our discipline is in good hands! Education was and continues to be my passion. It was a major area of focus during my time serving the society. Over the past three years, I have chatted with nearly 10,000 teachers from K through postgrad and have talked with an even greater number of students. From these meetings and discussions, it is crystal clear to me that our education system is producing an incredible group of young, enthusiastic scientists who I am certain will lead this ...

THE BOARD OF TRUSTEES, Group Insurance Plans for ACS Members is committed to expanding and improving the insurance and financial security products offered to ACS members. These valuable benefits help members safeguard personal assets, and they stay with you even if you change jobs or retire sooner than you expected. On the basis of the results of a member survey on insurance needs, the board is pleased to announce the introduction of two products: Medicare Supplemental Insurance (MediGap) and Medical Discount Cards that can be used for discounts on prescription drugs, dental and vision care, and other products and services. Details on these plans, as well as on all of our products, can be found at www.acs.org/insurance . MediGap is an important aspect of retiree health care, filling in the gaps that Medicare doesn’t cover. The Board of Trustees selected TransAmerica, a national provider rated A for financial strength by A.M. Best rating agency, as ...

THERE HAS BEEN a lot of interest in how the Committee on Nominations & Elections (N&E) generates the slate of nominees for the office of president-elect of ACS. This renewed interest has been stimulated by the fact that N&E has been working to refine the process at the behest of participants, councilors, and members of the society. Understanding the current process is a good foundation for all of us, one that should help us better comprehend the potential impact of the proposed changes that will be on the spring council agenda in 2010. The current process is formally described in the society’s Constitution and Bylaws, and its implementation is the responsibility of the 15 councilors of N&E who are elected by their peers. N&E is a very diverse and hard-working group of councilors. When I was asked to be a nominee for president-elect, I certainly did not fully appreciate the months of effort that N&E ...

PROUD TO BE A CHEMIST! This is more than just a phrase that has resonated with me throughout my presidential year; it is a core belief that reflects the indispensable role of chemistry in helping people. Chemistry connects us in many ways, and each connection can make a difference. I have connected through the ACS Network and Facebook with students who have contacted me to ask about next steps in their careers or which courses they should take to prepare for their entry into the field. In this month’s “Rxn’s and Sln’s” feature in the ACS magazine inChemistry , recent graduates were asked to write about the career paths they chose after earning bachelor’s degrees in the chemical sciences. ACS member and Project SEED alumna Alexandra Severino highlighted her journey from research scientist to high school chemistry teacher: “After graduating with a B.A. in chemistry I was unsure about my next step and decided to work ...

In response to the question "What is your favorite element?" the appeal of silicon is described.

THIS YEAR, one of my most important, although least visible, roles is serving as chair of the Board of Trustees, Group Insurance Plans for ACS Members. During this time of economic unrest, rising unemployment, and troubled insurance companies, the board of trustees wants you to know that the ACS member insurance plans stand on sound financial footing and that the staff and insurance professionals stand ready to serve all members. The board of trustees, composed of nine ACS member volunteers chosen for their diverse backgrounds and interests, reviews the insurance and financial security products offered to members as well as the companies that offer those products. In choosing New York Life Insurance as the underwriter for the ACS Group Insurance Plans, the board has placed the group insurance plans with a mutual company that continues to have a very strong and positive financial outlook even during these tough financial times. New York Life’s ...

WE IN ACS often talk about the value of diversity and the importance of accepting all those who seek us out. However, when you are the 800-pound gorilla in the room, your sheer size can be a deterrent to initiating and building a relationship. For this very reason, we as ACS members should make personal connections. We must be the first to extend a hand in friendship, with an open mind and a sincere willingness to learn. This past October, I had the incredible opportunity to participate in the 30th National Meeting of the American Indian Science & Engineering Society (AISES). This event, which took place in Anaheim, Calif., had more than 1,800 conference attendees. ACS was there to extend its hand in friendship and professional respect at this special anniversary event. ACS acknowledged the tremendous value that AISES has provided for American Indians and Alaskan Natives for the past three decades. I spoke with ...

WE BELIEVE STRONGLY in the ACS vision, “Improving people’s lives through the transforming power of chemistry.” It is a powerful and direct statement that truly underscores what we as chemists do for society: help people. Unfortunately, not everyone understands or believes that this is what chemists do. A more common perception is that chemists “mix things” or “blow stuff up.” To be successful, to make a dent in the misperceptions surrounding chemistry, chemists, and chemicals, ACS needs your help. Will you commit to helping put a human face on chemistry by building new relationships within your communities and across the globe? If so, the society needs you to create and provide educational opportunities and experiences to help the general public better understand that anything they can see, touch, taste, or smell—anything they can perceive—is composed of chemicals, the raw materials we use to create substances which improve people’s lives. In an effort to help ACS ...

A novel and convenient method for the apparent liquid phase generation of dimethylsilanone, Me2SiO (D1), based on readily obtainable reactants and employing conventional temperatures (50–150°) is reported herein. Platinum catalyzed hydrosilylation of vinyldimethylcaarbinoxydimethylsilane (I) appears to proceed by an exclusively intramolecular path to produce not only the expected 5-membered heterocyclic, 1,1,3,3-tetramethyl-2-oxa-1 silacyclopentane (V), but also the isomeric and highly unstable 4-membered siloxetane, 1,1,3,3,4-pentamethyl-2-oxa-1-silacyclobutane (IV). The intermediacy of IV is suggested by the products: i.e., 2-methyl-2-butene which is believed to arise along with Me2SiO from fragmentation of IV; D3 and D4 from D1 self-coupling; a 6-membered cyclic derived from insertion of D1 into the Si-O bond of IV, i.e., 1,1,3,3,5,5,6-heptamethyl-2,4-dioxa-1,3-disilacyclohexane (VI); a polymer which upon alkaline cracking produces more 6-ring (VI) but little or no 5-ring (V) suggesting that the polymer arose from copolymerization of D1, D2, and siloxetane (IV). Compound I is also an excellent thermolytic source of D1 as evidenced by the formation of the expected derivatives upon heating in the presence of known silanone traps.

Molecular structures of 26 organosilicon compounds have been optimized using ab initio calculations at the 3-21G* (modified) level. From these optimized structures, the internal coordinates have been deformed and the variation of the total molecular energy has been studied. Parameters for stretching and bending deformations are reported herein. The bending potential for the SiOSi bond which has an unusual flexibility is also included. Nonbonding interactions are described in terms of steric and electrostatic potentials. For systems which do not include bond resonance effects, torsional behavior is well described by steric potentials with van der Waals radii 20% larger than the previous values and simple electrostatic potential (monopole-monopole) with net atomic charges obtained from ab initio or Extended Huckel Theory calculations. The nonbonding potentials, as defined in this study, have an advantage in that they allow for the computation of torsional barriers without torsional potentials, in the case of single bonds where no additional electronic effects interfere. As an example, it is shown that no torsional potentials are necessary to estimate the torsional barriers in the case of ethane. The newly defined potentials are used to study the torsional barrier in hexamethyldisiloxane and the conformation of octamethylcyclotetrasiloxane (D4). The most stable calculated conformation of D4, coincides with the experimentally determined structure. This study shows that the most stable conformation is determined by the steric repulsion of methyl groups.