Contents 1. Introduction and Historical Background 3800 2. Thermodynamics, Kinetics, and Mechanisms of Processes Catalyzed by NHPI 3803 2.1. Characterization of PINO radical 3803 2.2. Electrochemical Behavior 3803 2.3. Thermochemistry 3803 2.4. Self-Decomposition of PINO Radical 3804 2.5. Kinetics of Reactions of PINO Radical 3805 2.6.

Int J Artif Organs ( 2011; : 9) 929-946 34 TITANIUM OXIDE AND ANTIBACTERIAL SURFACES IN BIOMEDICAL DEVICES Device-related infections: a clinical demand driving material science researchAn increasing number of clinical procedures requires the use of biomedical devices, whose widespread presence in modern therapeutic treatments is driving the demand for better performances and longer reliability. One of the major issues of both short-term devices and implantable prostheses is represented by device-related infections (DRIs) Accepted: August 31, 2011 rEViEW due to bacterial colonization and proliferation (1). About half of the 2 million cases of nosocomial infections that occur each year in the United States are associated with indwelling devices (2): these infections generally require a longer period of antibiotic therapy and repeated surgical procedures, resulting in potential risks for the patient and increased costs for the healthcare system. The planktonic bacteria that colonize a device surface tend to form a biofilm and the sessile bacterial cells, enclosed in a self-produced polymeric matrix of this kind, can withstand host immune responses and generally show extraordinary antibiotic resistance (3). Eventually, bacteria rapid multiply and disperse in planktonic form, giving rise

A series of peroxyl radical clocks has been developed and calibrated based on the competition between the unimolecular beta-fragmentation (k(beta)) of a peroxyl radical and its bimolecular reaction with a hydrogen atom donor (k(H)). These clocks are based on either methyl linoleate or allylbenzene and were calibrated directly with alpha-tocopherol or methyl linoleate, which have well-established rate constants for reaction with peroxyl radicals (k(H-tocopherol) = 3.5 x 10(6) M(-1) s(-1), k(H-linoleate) = 62 M(-1) s(-1)). This peroxyl radical clock methodology has been successfully applied to determine inhibition and propagation rate constants ranging from 10(0) to 10(7) M(-1) s(-1).

The oxidation of alcohols to aldehydes and ketones by air or oxygen under mild conditions (room temperature and atmospheric pressure), catalysed by persistent and non-persistent nitroxyl radicals in combination with transition metal salts, appears to be the most convenient of the numerous processes developed for these purposes. The thermochemistry, the kinetics, and the Hammett correlations have allowed us to establish, on a quantitative basis, the fundamental difference

15The oxidation of natural polysaccharides by TEMPO has become by now an "old chemical 16 reaction" which led to numerous studies mainly conducted on cellulose. This regioselective 17 oxidation of primary alcohol groups of neutral polysaccharides has generated a new class of 18 polyuronides not identified before in nature, even if the discovery of enzymes promoting an 19 analogous oxidation has been more recently reported. Around the same time, the scientific 20 community discovered the surprising biological and techno-functional properties of these 21 anionic macromolecules with a high potential of application in numerous industrial fields. The 22 objective of this review is to establish the state of the art of TEMPO chemistry applied to 23 polysaccharide oxidation, its history, the resulting products, their applications and the 24 associated modifying enzymes. 25

The vibrational dynamics of a new class of cross‐linked polymers obtained from both native and modified cyclodextrin, referred to as cyclodextrin nanosponges, is here investigated. The main purpose is to spot the structure of these materials at molecular level unlikely to be characterized by diffraction methods due to the low or null degree of crystallinity. The analysis of the spectral features of the vibrational bands observed between 1650 and 1800 cm−1 in both Raman and infrared spectra, and assigned to the carbonyl stretching modes of the polymeric network, is performed by using band deconvolution procedures. At the same time, a detailed inspection of the low‐wavenumber vibrational dynamics of these polymers is carried out, focusing on the modifications occurring on the so‐called boson peak. The simultaneous analysis of different wavenumber ranges in Raman and infrared spectra of cyclodextrin nanosponges allows us to develop a reliable strategy for exploring both the cross‐linking degree and the elastic properties of these innovative materials. The overall results give a complete characterization of the structural and dynamical properties of the system, in turn strictly connected to the entrapment/transport ability of these polymeric matrices. Copyright © 2013 John Wiley & Sons, Ltd.

Adsorbent sponges for water remediation were prepared using TEMPO-oxidized cellulose nanofibers (TOCNFs) as three-dimensional scaffolds, and branched polyethyleneimine (bPEI, 25 KDa) as the cross-linking agent. TOCNFs were suspended in aqueous solution in the presence of variable amounts of bPEI. The mixtures were first freeze-dried and then thermally treated (from 60 to 102 °C over 10 h) promoting the formation of amide bonds between the carboxylic groups of TOCNF and the primary amines of bPEI. The resulting materials, which were characterized by FTIR and 13C CP-MAS NMR spectroscopy, scanning electron microscopy, and elemental analysis, showed higher chemical and mechanical stability in water than non-reticulated cellulose composites. The high adsorption capability of the new sponges was verified for different organic pollutants (p-nitrophenol, 2,4,5-trichlorophenol, and amoxicillin), and heavy metal ion pollutants (Cu, Co, Ni, Cd), indicating their potential for water decontamination

The oxidation of N-alkylamides by O(2), catalyzed by N-hydroxyphthalimide (NHPI) and Co(II) salt, leads under mild conditions to carbonyl derivatives (aldehydes, ketones, carboxylic acids, imides) whose distribution depends on the nature of the alkyl group and on the reaction conditions. Primary N-benzylamides lead to imides and aromatic aldehydes at room temperature without any appreciable amount of carboxylic acids, while under the same conditions nonbenzylic derivatives give carboxylic acids and imides with no trace of aldehydes, even at very low conversion. These results are explained through hydrogen abstraction by the phthalimide-N-oxyl (PINO) radical, whose reactivity with benzyl derivatives is governed by polar effects, so that benzylamides are much more reactive than the corresponding aldehydes. The enthalpic effect is, however, dominant with nonbenzylic amides, making the corresponding aldehydes much more reactive than the starting amides. The importance of the bond dissociation energy (BDE) of the O-H bond in NHPI is emphasized.