The assignment of the vibrational spectra of lithium hydroxide monohydrate, LiOH·H(2)O, has been controversial for more than half-a-century. Here we show that only the combination of all three forms of vibrational spectroscopy: infrared, Raman and inelastic neutron scattering spectroscopies coupled with periodic-density functional theory calculations is able to satisfactorily assign the spectra. All previous work based on empirical criteria is, at least partially, incorrect. The librational modes of water do not follow the expected rock > wag > twist order and the calculations indicate that complete or partial deuterium substitution would not be useful in assigning the modes.

Steps for the refolding of proteins from solubilized inclusion bodies or misfolded product often represent bottlenecks in process development, where optimal conditions are typically derived empirically. To expedite refolding optimization, microwell screening may be used to test multiple conditions in parallel. Fast, accurate, and reproducible assays are required for such screening processes, and the results derived must be representative of the process at full scale. This article demonstrates the use of these microscale techniques to evaluate the effects of a number of additives on the refolding of IGF-1 from denatured inclusion bodies, using an established HPLC assay for this protein. Prior to this, microwell refolding was calibrated for scale-up using hen egg-white lysozyme (HEWL) as an initial model protein, allowing us to implement and compare several assays for protein refolding, including turbidity, enzyme activity, and chromatographic methods, and assess their use for microwell-based experimentation. The impact of various microplate types upon protein binding and loss is also assessed. Solution mixing is a key factor in protein refolding, therefore we have characterized the effects of different methods of mixing in microwells in terms of their impact on protein refolding. Our results confirm the applicability and scalability of microwell screening for the development of protein refolding processes, and its potential for application to new inclusion body-derived protein products.

Polymers containing 9,10-phenanthraquinone moieties as part of an extended π-electron system have been prepared by Suzuki couplings between 2,7- or 3,6-dibromophenanthraquinone and 9,9-dioctylfluorene-2,7-diboronic acid bispinacol ester. Closely related model compounds were prepared similarly. All the products were characterised by FT-IR, 1H NMR and UV-vis/fluorescence spectroscopy and, where relevant, mass spectrometry. Cyclic voltammetry measurements indicate that these materials display electron affinities of up to 4.0 eV. This value is one of the highest reported for conjugated polymers.

Microbiology is important to industry therefore rapid and statistically representative measurements of cell physiological state, proliferation, and viability are essential if informed decisions about fermentation bioprocess optimization or control are to be made, because process performance will depend largely on the number of metabolically active viable cells. Samples of recombinant Escherichia coli W3110, containing the gene for the D1.3 anti-lysozyme Fab fragment under the control of the lac-based expression system, were taken at various stages from fed-batch fermentation processes and stained with a mixture of bis-(1,3-dibutylbarbituric acid) trimethine oxonol and propidium iodide (PI/BOX). Where appropriate, measurements of dissolved oxygen tension (DOT), OD600nm and Fab concentration were made. Depending on time of induction the maximum amount of Fab accumulating in the supernatant varied quite markedly from 1 to 4 microg ml(-1) as did subsequent cell physiological state with respect to PI/BOX staining with a concomitant drop in maximum biomass concentration. Depending on point of induction a fourfold increase in Fab production could be achieved accompanied by a approximately 50% drop in maximum biomass concentration but with a higher proportion of viable cells as measured by multiparameter flow cytometry.

A new, highly efficient synthesis of chiral β 2,3-disubstituted-β-amino acid derivatives has been developed, based on an allylation procedure employing allene and a catalytic Pd/In bimetallic process.

Anthracene-based, H +-driven, ‘off–on–off’ fluorescent PET (photoinduced electron transfer) switches are immobilized on organic and inorganic polymeric solids in the form of Tentagel ® and silica, respectively. The environment of the organic bead displaces apparent switching thresholds towards lower pH values whereas the Si–O − groups of silica electrostatically cause the opposite effect. These switches are ternary logic gate tags, one of which can be particularly useful in strengthening molecular computational identification (MCID) of small solid objects.

Novel non-PEG derived polyether resins, coined SLURPS (Superior Liquid Uptake Resins for Polymer-supported Synthesis), were studied for their performance in solid-phase synthesis. Novel amino functional resins, SLURPS-NH2, were prepared with a loading of up to 8.5 mmol/g and employed successfully in the solid-phase synthesis of Leu-Enkephalin. The peptide was obtained with the same purity when compared to its synthesis with commercial standard poly(dimethyl acrylamide) resins. Furthermore we show loading and cleavage of aromatic carboxylic acids in excellent yield. The advantageous solvent compatibility of our support was demonstrated through the biphasic dihydroxylation of alkenes with OsO4 in t-BuOH/water mixtures producing bound 1,2-diols and synthesis and removal of a bound oxime using ethanol/water mixtures both in excellent yields. Reactions were easily monitored by gel-phase NMR and FTIR. These results show that SLURPS are very well suited for organic transformations using highly polar solvent mixtures and reagents and at much higher loading levels than standard amphiphilic resins of similar solvent compatibility.

Protective antigen (PA) is an 83 kDa protein which, although essential for toxicity of Bacillus anthracis, is harmless and an effective vaccine component. In vivo it undergoes receptor binding, proteolysis, heptamerisation and membrane insertion. Here we probe the response of PA to denaturants, temperature and pH. We present analyses (including barycentric mean) of the unfolding and refolding behavior of PA and reveal the origin of two critical steps in the denaturant unfolding pathway in which the first step is a calcium and pH dependent rearrangement of domain 1. Thermal unfolding fits a single transition near 50 °C. We show for the first time circular dichroism (CD) spectra of the heptameric, furin-cleaved PA63 and the low-pH forms of both PA83 and PA63. Although only PA63 should reach the acidic endosome, both PA83 and PA63 undergo similar acidic transitions and an unusual change from a β II to a β I CD spectrum.

The axillary skin is cosmetically important with millions of consumers daily applying antiperspirant/deodorant products. Despite this, we know virtually nothing about axillary skin or how antiperspirant use impacts upon it. To characterize axillary stratum corneum and determine whether this is a unique skin type, we have evaluated a range of skin parameters, comparing these with the volar forearm. Trans‐epidermal water loss and corneosurfametry revealed a reduced barrier function in the axilla. However, application of antiperspirant had no effect upon these barrier properties. High performance thin layer chromatography analysis of stratum corneum lipids demonstrated statistically elevated levels of fatty acids, ceramide and particularly cholesterol in the axilla. This modification of barrier lipid ratios appeared to result in a more ordered lipid lamellae phase behaviour, as determined by attenuated total reflectance Fourier transform infrared spectroscopy, with transition phase changes occurring at higher temperatures. Morphological differences were also seen in the cells of the axillary stratum corneum. Microscopic evaluation of axillary‐cornified envelopes revealed them to be smaller, indicative of a shorter stratum corneum turnover. However, there appeared to be no significant difference corneocyte maturation. ‘Skin dryness’ squamometry measurements indicated that the axillary stratum corneum retained desquamated material on its surface more than on the forearm. This correlated with decreased levels of the desquamatory stratum corneum chymotryptic enzyme in the surface layers of the skin. These results indicate that the axilla has a distinct phenotype. Paper presented at the 22nd IFSCC Congress 2002, Edinburgh, Scotland