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Gellan is an exopolysaccharide produced in high yield by the non-pathogenic bacterium Sphingomonas elodea ATCC 31461. In this study, four carboxylated derivatives of gellan (OG-1, OG-2, OG-3 and OG-4) with different uronics acid content were prepared using the TEMPO (nitroxyl radical 2,2,6,6-tetramethylpiperidine-1-oxyl radical) mediated oxidation and their antioxidant activities were investigated including scavenging activity of hydroxyl, superoxide anion and 1,1-diphenyl-2-picryl-hydrazyl radicals. The results of chemical analysis and (13)C NMR spectrums indicated that the modification was successful. In addition, certain derivative exhibited stronger antioxidant activity compared to that of native ones. The high uronic acids derivative (OG-4) showed the most excellent antioxidant activity in three assays. These results suggested the potential of TEMPO-mediated oxidation in developing water-soluble antioxidative polysaccharides from gellan still taking advantage of its low-cost production. The original carbohydrate structure of OG-4 derivative might find use as surrogates of ulvan, a cell-wall polysaccharides extracted from green seaweeds Ulva sp.

The produced, purified and deacylated gellan exopolysaccharide was subjected to regiospecific oxidation at C6 with NaOCl in the presence of 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO) and NaBr in aqueous solution at pH 10. As with other polysaccharides, a high selectivity of oxidation was observed. The high performance anion-exchange chromatography (HPAEC) and 13 C NMR analysis of the TEMPO-oxidized products was used to confirm that the C6 primary hydroxyl groups of deacylated gellan were completely converted to carboxylate groups. Thus, after the addition of 7.5 mmol of NaClO per gram of polysaccharide, a new and original water-soluble rhamnoglucuronan polymer was obtained quantitatively with homogeneous chemical structures. This original carbohydrate might find use as surrogates of ulvan, a sulfated cell-wall polysaccharides extracted from green seaweeds (Ulva species), in pharmaceutical and medical areas.

Glycosaminoglycan-like polysaccharides were prepared from Rhizobium sp. T1 polysaccharide using the TEMPO (nitroxyl radical 2,2,6,6-tetramethylpiperidine-1-oxyl radical) mediated oxidation. The structure of this new polyglucuronic acid sodium salt was analyzed by 13 C NMR spectra and HPAEC–PAD chromatography. Therefore, new polysaccharide containing only glucuronic acid monomers in both β -(1,3) and β -(1,4) linkage was obtained by the complete TEMPO-mediated oxidation of C6 primary hydroxyl groups of glucose of glucoglucuronan from Rhizobium sp. T1. Sulphation of this β -(1,3), β -(1,4)-polyglucuronic acid sodium salt was carried out using SO 3 /DMF reagent. These results suggested a new synthetic route using both TEMPO-mediated oxidation and sulphation of polysaccharides from Rhizobium sp. in developing glycosaminoglycans mimic to enhance the profitability of its low-cost production and processing industries. This novel carbohydrate derivative might find use as cheaper surrogates of glycosaminoglycans in the cosmetics and pharmaceutical fields.

Infrastructures to provide access to custom integrated hardware manufacturing facilities are important because they allow Students and Researchers to access professional facilities at a reasonable cost, and they allow Companies to access small volume production, otherwise difficult to obtain directly from manufacturers. This paper is reviewing the most recent developments at CMP, as well as other services similar to CMP. These services helped the development of microelectronics for the EE&CS communities. Other communities might take advantage the same way, like the BioMed community. Examples of BioMed applications using CMOS and MEMS are given. The conclusion includes statements for the BioMed community as well as statements on where manufacturing infrastructures like CMP should go, considering technical developments towards More Moore, More than Moore, as well as statements related to globalization.

A novel time-saving and cost-effective release technique has been developed and is described. The physical nature of the process is explained in combination with experimental observations. The results of the flash release process are compared with those of freeze-drying and supercritical CO2 releasing. It is demonstrated that the new technique is not only simpler but it also gives better yield for long cantilevers. Furthermore, it is shown that the process can be used successfully for complex MEMS devices that consist of multiple-structural layers, but which do not contain membrane-like structures.