Influence of a pore-forming agent on swelling, network parameters, and permeability of poly(ethylene glycol)-crosslinked poly(methyl vinyl ether-co-maleic acid) hydrogels:Application in transdermal delivery systems

We characterized hydrogels, prepared from aqueous blends of poly(methyl vinyl ether-co-maleic acid) (PMVE/MA) and poly(ethylene glycol) (PEG 10,000 Daltons) containing a pore-forming agent (sodium bicarbonate, NaHCO ). Increase in NaHCO content increased the equilibrium water content (EWC) and average molecular weight between crosslinks (M ) of hydrogels. For example, the %EWC was 731, 860, 1109, and 7536% and the M was 8.26, 31.64, 30.04, and 3010.00 × 10 g/mol for hydrogels prepared from aqueous blends containing 0, 1, 2, and 5% w/w of NaHCO , respectively. Increase in NaHCO content also resulted in increased permeation of insulin. After 24 h, percentage permeation was 0.94, 3.68, and 25.71% across hydrogel membranes prepared from aqueous blends containing 0, 2, and 5% w/w of NaHCO , respectively. Hydrogels containing the pore-forming agent were fabricated into microneedles (MNs) for transdermal drug delivery applications by integrating the MNs with insulin-loaded patches. It was observed that the mean amount of insulin permeating across neonatal porcine skin in vitro was 20.62% and 52.48% from hydrogel MNs prepared from aqueous blends containing 0 and 5% w/w of NaHCO . We believe that these pore-forming hydrogels are likely to prove extremely useful for applications in transdermal drug delivery of biomolecules. © 2012 Wiley Periodicals, Inc.

Anisotropy parameters in two-color two-photon above-threshold ionization

We employ the time-dependent R-matrix (TDRM) method to calculate anisotropy parameters for positive and negative sidebands of selected harmonics generated by two-color two-photon above-threshold ionization of argon. We consider odd harmonics of an 800-nm field ranging from the 13th to 19th harmonic, overlapped by a fundamental 800-nm IR field. The anisotropy parameters obtained using the TDRM method are compared with those obtained using a second-order perturbation theory with a model potential approach and a soft photon approximation approach. Where available, a comparison is also made to published experimental results. All three theoretical approaches provide similar values for anisotropy parameters. The TDRM approach obtains values that are closest to published experimental values. At high photon energies, the differences between each of the theoretical methods become less significant.

An evaluation of the capability of a biolayer interferometry biosensor to detect low-molecular-weight food contaminants

The safety of our food is an essential requirement of society. One well-recognised threat is that of chemical contamination of our food, where low-molecular-weight compounds such as biotoxins, drug residues and pesticides are present. Low-cost, rapid screening procedures are sought to discriminate the suspect samples from the population, thus selecting only these to be forwarded for confirmatory analysis. Many biosensor assays have been developed as screening tools in food contaminant analysis, but these tend to be electrochemical, fluorescence or surface plasmon resonance based. An alternative approach is the use of biolayer interferometry, which has become established in drug discovery and life science studies but is only now emerging as a potential tool in the analysis of food contaminants. A biolayer interferometry biosensor was assessed using domoic acid as a model compound. Instrument repeatability was tested by simultaneously producing six calibration curves showing replicate repeatability (n = 2) ranging from 0.1 to 6.5 % CV with individual concentration measurements (n = 12) ranging from 4.3 to 9.3 % CV, giving a calibration curve midpoint of 7.5 ng/ml (2.3 % CV (n = 6)). Reproducibility was assessed by producing three calibration curves on different days, giving a midpoint of 7.5 ng/ml (3.4 %CV (n = 3)). It was further shown, using assay development techniques, that the calibration curve midpoint could be adjusted from 10.4 to 1.9 ng/ml by varying assay parameters before the simultaneous construction of three calibration curves in matrix and buffer. Sensitivity of the assay compared favourably with previously published biosensor data for domoic acid. © 2013 Springer-Verlag Berlin Heidelberg.

Stout: Cloudy's Atomic and Molecular Database

We describe a new atomic and molecular database we developed for use in the spectral synthesis code Cloudy. The design of Stout is driven by the data needs of Cloudy, which simulates molecular, atomic, and ionized gas with kinetic temperatures and densities spanning the low-to high-density limits. The radiation field between photon energies 10−8 Ry and 100 MeV is considered, along with all atoms and ions of the lightest 30 elements, and ~102 molecules. For ease of maintenance, the data are stored in a format as close as possible to the original data sources. Few data sources include the full range of data we need. We describe how we fill in the gaps in the data or extrapolate rates beyond their tabulated range. We tabulate data sources both for the atomic spectroscopic parameters and for collision data for the next release of Cloudy. This is not intended as a review of the current status of atomic data, but rather a description of the features of the database which we will build upon.

Magnitude differences in bioactive compounds, chemical functional groups, fatty acid profiles, nutrient degradation and digestion, molecular structure and metabolic characteristics of protein in newly developed yellow-seeded and black-seeded canola lines.

Recently, new lines of yellow-seeded (CS-Y) and black-seeded canola (CS-B) have been developed with chemical and structural alteration through modern breeding technology. However, no systematic study was found on the bioactive compounds, chemical functional groups, fatty acid profiles, inherent structure, nutrient degradation and absorption, or metabolic characteristics between the newly developed yellow- and black-seeded canola lines. This study aimed to systematically characterize chemical, structural, and nutritional features in these canola lines. The parameters accessed include bioactive compounds and antinutrition factors, chemical functional groups, detailed chemical and nutrient profiles, energy value, nutrient fractions, protein structure, degradation kinetics, intestinal digestion, true intestinal protein supply, and feed milk value. The results showed that the CS-Y line was lower (P ≤ 0.05) in neutral detergent fiber (122 vs 154 g/kg DM), acid detergent fiber (61 vs 99 g/kg DM), lignin (58 vs 77 g/kg DM), nonprotein nitrogen (56 vs 68 g/kg DM), and acid detergent insoluble protein (11 vs 35 g/kg DM) than the CS-B line. There was no difference in fatty acid profiles except C20:1 eicosenoic acid content (omega-9) which was in lower in the CS-Y line (P < 0.05) compared to the CS-B line. The glucosinolate compounds differed (P < 0.05) in terms of 4-pentenyl, phenylethyl, 3-CH3-indolyl, and 3-butenyl glucosinolates (2.9 vs 1.0 μmol/g) between the CS-Y and CS-B lines. For bioactive compounds, total polyphenols tended to be different (6.3 vs 7.2 g/kg DM), but there were no differences in erucic acid and condensed tannins with averages of 0.3 and 3.1 g/kg DM, respectively. When protein was portioned into five subfractions, significant differences were found in PA, PB1 (65 vs 79 g/kg CP), PB2, and PC fractions (10 vs 33 g/kg CP), indicating protein degradation and supply to small intestine differed between two new lines. In terms of protein structure spectral profile, there were no significant differences in functional groups of amides I and II, α helix, and β-sheet structure as well as their ratio between the two new lines, indicating no difference in protein structure makeup and conformation between the two lines. In terms of energy values, there were significant differences in total digestible nutrient (TDN; 149 vs 133 g/kg DM), metabolizable energy (ME; 58 vs 52 MJ/kg DM), and net energy for lactation (NEL; 42 vs 37 MJ/kg DM) between CS-Y and CS-B lines. For in situ rumen degradation kinetics, the two lines differed in soluble fraction (S; 284 vs 341 g/kg CP), potential degradation fraction (D; 672 vs 590 g/kg CP), and effective degraded organic matter (EDOM; 710 vs 684 g/kg OM), but no difference in degradation rate. CS-Y had higher digestibility of rumen bypass protein in the intestine than CS-B (566 vs 446 g/kg of RUP, P < 0.05). Modeling nutrient supply results showed that microbial protein synthesis (MCP; 148 vs 171 g/kg DM) and rumen protein degraded balance (DPB; 108 vs 127 g/kg DM) were lower in the CS-Y line, but there were no differences in total truly digested protein in small intestine (DVE) and feed milk value (FMV) between the two lines. In conclusion, the new yellow line had different nutritional, chemical, and structural features compared to the black line. CS-Y provided better nutrient utilization and availability.

Implication of modified molecular structure of lipid through heat-related process to fatty acids supply in Brassica carinata seed.

This study was conducted to explore the effect of different autoclave heating times (30, 60 and 90 min) on fatty acids supply and molecular stability in Brassica carinata seed. Multivariate spectral analyses and correlation analyses were also carried out in our study. The results showed that autoclaving treatments significantly decreased the total fatty acids content in a linear fashion in B. carinata seed as heating time increased. Reduced concentrations were also observed in C18:3n3, C20:1, C22:1n9, monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA), omega 3 (ω-3) and 9 (ω-9) fatty acids. Correspondingly, the heated seeds showed dramatic reductions in all the peak intensities within lipid-related spectral regions. Results from agglomerative hierarchical cluster analysis (AHCA) and principal component analysis (PCA) indicated that the raw oilseed had completely different structural make-up from the autoclaved seeds in both CH3 and CH2 asymmetric and symmetric stretching region (ca. 2999–2800 cm−1) and lipid ester Cdouble bond; length as m-dashO carbonyl region (ca. 1787–1706 cm−1). However, the oilseeds heated for 30, 60 and 90 min were not grouped into separate classes or ellipses in all the lipid-related regions, indicating that there still exhibited similarities in lipid biopolymer conformations among autoclaved B. carinata seeds. Moreover, strong correlations between spectral information and fatty acid compositions observed in our study could imply that lipid-related spectral parameters might have a potential to predict some fatty acids content in oilseed samples, i.e. B. carinata. However, more data from large sample size and diverse range would be necessary and helpful to draw up a final conclusion.