bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fabrication of surface‐enhanced Raman scattering‐active ZnO/Ag composite microspheres
Authors: Song Wei , Wang Yanfei , Hu Hailong , Zhao Bing 
Published: June 2007

AbstractWe show in this paper how zinc oxide (ZnO)/silver (Ag) composite microspheres can be prepared by the reduction of Ag(NH3)2+ with the reducing agent formaldehyde in aqueous solution on the surface of ZnO microspheres. During the preparation, Sn2+ was absorbed on the surface of ZnO microspheres for sensitization and activation, and then Ag(NH3)2+ was reduced to Ag nanoparticles by the reducing agent to obtain ZnO/Ag composite microspheres. SEM and TEM images revealed silver nanoparticles with a diameter ranging from tens to 100 nm. X‐Ray photoelectron spectra (XPS), X‐ray diffraction (XRD) patterns and UV‐vis spectra were used to characterize the structure of the ZnO/Ag composite microspheres. The origin of the surface‐enhanced Raman scattering properties was traced to the surface of the ZnO/Ag composite microspheres. The enhancement factor was estimated in detail, and the enhancement mechanism for the SERS effect was also investigated. Copyright © 2007 John Wiley & Sons, Ltd.
Detection of protein molecules by surface‐enhanced Raman spectroscopy‐based immunoassay using 2–5 nm gold nanoparticle lables
Authors: Manimaran M. , Jana Nikhil R. 
Published: June 2007

AbstractHere we report the synthesis of 2–5 nm size gold nanoparticle labels for surface‐enhanced Raman Spectroscopy (SERS) based immunoassay to detect protein molecules. The Au nanoparticles were conjugated with fluorescein isothiocyanate (FITC) and goat anti‐h‐IgG (immunoglobin) and the resultant particles were used for the detection of h‐IgG. Commercially available nitrocellulose strip and silver enhancement method were used for SERS‐based immunoassays. The FITC acts as a Raman probe, and vibrational fingerprint of this molecule was used for the detection of h‐IgG in concentration ranging from 1 to 100 ng/µl. Our Raman probe is robust and small in size and has high water solubility with minimum steric effect during antigen–antibody binding. Copyright © 2007 John Wiley & Sons, Ltd.
Using Raman spectroscopy to investigate donor–acceptor reactions in the formamide/dimethylsulfoxide/acetonitrile system
Authors: Alves Wagner A. , Santos Paulo S. 
Published: June 2007

AbstractRaman spectra of binary and ternary solvent systems in different concentrations were carried out. The mixtures containing equimolar quantities of dimethylsulfoxide (DMSO) and acetonitrile (ACN), or those in different compositions, do not show any spectral evidence for the formation of a Lewis acid–base adduct. On the contrary, the formamide (FA), DMSO and ACN mixtures exhibit new bands. In the S stretching region, the band at 1025 cm−1 is assigned to the FA–DMSO adduct whereas, in the C stretching region, the 2257 cm−1 band corresponds to the FA–ACN adduct. The positions of these two new bands in the present system are in agreement with our recent works. In addition, in the NH2 bending region, the 1613 cm−1 band has been described as a mixture of both adducts. Quantitative analyses performed in the S and C stretching regions show that the association extent for the FA–DMSO adduct is greater than for the FA–ACN adduct, and this is in excellent agreement with the acid–base concepts commonly used to nonaqueous solvents. Preferential interactions between FA molecules as well as their dependence on the ternary mixture composition are also discussed. The results described here open up new possibilities to study the acid–base reactions nature involving FA adducts and can be useful for a better description of biological systems in which peptide groups have a special role. Copyright © 2007 John Wiley & Sons, Ltd.
General criterion to discern between coherent and incoherent synthesis of broadband coherent anti‐Stokes Raman spectra
Authors: Marrocco Michele 
Published: June 2007

AbstractRecently, the ordinary qualitative criterion on how to distinguish between coherent and incoherent convolutions of broadband coherent anti‐Stokes Raman (CARS) signals generated by degenerate pump lasers has been revised in view of a quantitative analysis. The revision has established that incoherent CARS approach can be justified as unitary limit of the function $\sqrt{\pi} \Gamma \exp [(\Gamma/\sigma_{1})^{2}]$] erfc(Γ/σ1)/σ1, where Γ and σ1 are respectively the spectral widths of the Raman line and the degenerate pump lasers. The result was, however, limited to nonoverlapping Raman lines. In this work, the extension to a more common situation of closely spaced Raman transitions is considered. For large overlap between adjacent Raman lines, the new analysis suggests significant deviations from the previous result. Weak line mixing is also taken into consideration. Nonetheless, all types of deviations are characterized by a common tendency toward the incoherent limit. Copyright © 2007 John Wiley & Sons, Ltd.
Micro‐Raman and stratigraphic studies of the paintings on the ‘Cembalo’ model musical instrument (A.D. 1650) and laser‐induced degradation of the detected pigments
Authors: De Santis Alberto , Mattei Elisabetta , Pelosi Claudia 
Published: June 2007

AbstractMicro‐fragments of the painted part of the ‘Cembalo’ model by Michele Todini (1625–1689) are investigated. The technique used for painting the terracotta base was studied via the stratigraphic analyses. No background layer of inorganic materials, e.g. gypsum, was found. To prevent absorption effects due to the terracotta porosity, a very thin layer of proteinaceous material was probably used. The micro‐Raman analyses have revealed the use of pigments currently used in the post‐Renaissance period (lead white, indigo, yellow of iron hydroxide, gypsum, hematite and carbon black) mixed with a pigment, the Prussian blue, discovered in A.D. 1704. This raises the authenticity problem of the work of art, a problem analysed and discussed in presenting the history of the work of art, and after the pigment study. The presence of degraded lead white is recognized via the laser‐induced degradation of the irradiated material. The possibility of a restoring action of the painted parts, as opposite to the non‐originality of the work, is considered and discussed. Since most part of the investigated pigments shows laser‐induced effects, a careful study of this phenomenon is performed by using the modern counterparts of the ancient pigments. For different laser powers, the temperatures of the investigated zones have been obtained via the detailed balance principle and connected to the laser‐induced degradation effects. Copyright © 2007 John Wiley & Sons, Ltd.
Differences in quality and quantity of transgenic component in Roundup Ready soybean during bean curd preparation
Authors: Chen Ying , Wang Zhengfu , Ge Yiqiang , Wang Yuan 
Published: June 2007

AbstractUsing 2.5% (w/w) transgenic Roundup Ready soybean as raw material, the effects of critical processing procedures on the fragment sizes of endogenous gene lectin and transgenic gene epsps and the quantity of transgenic component during bean curd preparation were analysed. The results showed that the different processing procedures differed in their impact on the degradation of endogenous and transgenic genes and that the transgenic content of the intermediate products and final product was consequently changed. Physical mechanical action such as jordaning caused both endogenous and transgenic genes to degrade but had more effect on the latter. The jordaning process degraded the DNA of endogenous gene from 1883 to 836 bp and that of transgenic gene from 1512 to 408 bp. The adding CaSO4 process, predominantly a chemical reaction, had less influence on the transgenic gene than on the endogenous gene, the latter being degraded from 836 to 407 bp. The extrusion moulding process resulted in a significant degradation of DNA in transgenic gene from 408 to 190 bp but had no obvious effect on the endogenous gene. After the critical processing procedures of jordaning, syruping, adding CaSO4 and extrusion moulding during bean curd preparation the transgenic content of the intermediate products and final product was 1.656, 0.435, 1.150 and 0.797% respectively. Copyright © 2007 Society of Chemical Industry
Studies on the synthesis and properties of hydroxypropyl derivatives of cassava (Manihot esculenta Crantz) starch
Authors: Jyothi Alummoottil N , Moorthy Subramoney N , Rajasekharan Kallikat N 
Published: June 2007

AbstractCassava starch was subjected to hydroxypropylation in three different media, which included water, water in the presence of a phase transfer catalyst, and 2‐propanol, all at 30 ± 2 °C for 24 h. Propylene oxide was used in four different concentrations (50, 100, 150 and 200 g kg−1 of starch dry weight). The products were characterized by determining their molar substitution (MS), structural and functional properties. The analyses were done in triplicate and the data were analyzed using the statistical package 8.01. The MS of the products ranged from 0.26 to 1.41. The MS of the hydroxypropyl derivatives were found to be higher when the reaction was carried out in the aqueous medium in the presence of tetrabutylammonium bromide, a phase transfer catalyst, when compared to the reaction in 2‐propanol, which was found to be not very effective at 30 ± 2 °C. The etherification altered the granular properties of starch, as could be seen from scanning electron micrographs. Hydroxypropylation resulted in starch pastes which were stable and with higher swelling volume, solubility, light transmittance and water binding capacity as compared to native starch. The hydroxypropyl starches showed significantly lower pasting temperatures and setback viscosities. The enzyme digestibility of the derivatives was seen to decrease with increase in MS and there was a significant reduction in the syneresis of the starch pastes of hydroxypropyl derivatives. Texture profile analysis showed that hydroxypropylated starch gels exhibited higher hardness, springiness (elasticity) and gumminess and lower cohesiveness than the native starch. Copyright © 2007 Society of Chemical Industry
Effect of processing and cooking on the content of minerals and protein in pasta containing buckwheat bran flour
Authors: Manthey Frank A , Hall Clifford A 
Published: June 2007

AbstractResearch was conducted to determine the effect of processing and cooking on the ash content and mineral composition and on protein content and amino acid composition of spaghetti that was fortified with 250 g kg−1 buckwheat bran flour (BBF). Extrusion and drying temperature had little or no effect on ash and mineral content of spaghetti containing BBF. Drying temperature did not affect protein content; however, a 31% reduction in lysine content was observed in spaghetti containing BBF dried at 90 °C. Cooking spaghetti fortified with BBF reduced ash content by 28%. Reduction in ash content was reflected by an average decrease in potassium of 62%, in copper of 45%, and in zinc of 11%. Cooking had little or no effect on content of calcium, iron, magnesium, or manganese. As a result of material leaching from spaghetti during cooking, the protein content and content of each amino acid (db) were greater in cooked than uncooked spaghetti. Copyright © 2007 Society of Chemical Industry
Production of low antigenic cheese whey protein hydrolysates using mixed proteolytic enzymes
Authors: Shin Hyun Soo , Kim Sang Bum , Kang Soo Cheol , Khan Muhammad Ajmal , Kim Hyeon Shup , Shin Hyun Jung , Chang Chi Hoon 
Published: June 2007

AbstractThis study examined the effect of different proteolytic enzymes on the production of cheese whey protein (CWP) hydrolysates with low antigenicity. Four enzyme combinations (1:1) trypsin + papain W‐40 (TP), trypsin + neutrase 1.5 (TN), papain W‐40 + protease S (PP) and papain W‐40 + neutrase 1.5 (PN) were added at the rate of 1% of the CWP and it was incubated for 15, 30, 60, 90, 120 and 180 min at 50 °C. CWP hydrolysis and its non‐protein nitrogen concentrations were higher with TP and TN compared with PP and PN at all incubation times. The SDS‐PAGE revealed complete removal of α‐lactalbumin (α‐LA) and β‐lactoglobulin (β‐LG) from hydrolysates produced by trypsin‐containing enzyme mixtures. Reverse‐phase HPLC analysis ascertained the CWP hydrolysis and SDS‐PAGE results. The lowest antigenicity in CWP hydrolysates was observed with the use of trypsin‐containing enzyme mixtures compared with other enzyme combinations. Present results suggested that TP and TN combinations were the most effective for CWP hydrolysis for the removal of β‐LG from CWP. Further research is warranted to identify the peptides in CWP hydrolysates produced with these enzyme combinations that may help enhance the utilisation of whey protein in human food. Copyright © 2007 Society of Chemical Industry
Influence of agricultural practices on the quality of sweet pepper fruits as affected by the maturity stage
Authors: Pérez‐López Antonio José , del Amor Francisco Moisés , Serrano‐Martínez Ana , Fortea María Isabel , Núñez‐Delicado Estrella 
Published: June 2007

AbstractBackground:Peppers are popular vegetables because of their colour, taste and nutritional value. The levels of vitamin C, carotenoids and phenolic compounds in peppers and other vegetables depend on several factors, including cultivar, agricultural practice and maturity stage.Results:In this study the effects of maturation and type of agricultural practice (organic or conventional) on the ascorbic acid, total carotenoid and total phenolic contents and colour parameters of sweet peppers (Capsicum annuum cv. Almuden) grown in a controlled greenhouse were determined. Levels of vitamin C, phenolic compounds and carotenoids increased during ripening, with red sweet peppers having higher contents of these bioactive compounds. Moreover, peppers grown under organic culture had higher vitamin C, phenolic and carotenoid levels than those grown under conventional culture. With respect to colour parameters, organic red peppers had higher values of L*, a*, b*, C* and Hab than conventional red peppers, giving them a higher intensity of red colour.Conclusion:Thus organic farming had a positive effect on the nutritional content of peppers, increasing the vitamin C activity and the level of phenolic compounds, both implicated in the antioxidant activity of vegetables, and the content of carotenoids, implicated in the colour variance observed in pepper fruits. Copyright © 2007 Society of Chemical Industry
Chemical genetics: catalysing pathway exploration and new target discovery
Authors: Armstrong Joshua I 
Published: June 2007

AbstractChemical genetics couples the availability of diverse chemistry with the strengths of molecular genetics to dissect signalling pathways in complex organisms. Plant biology laboratories have integrated this approach into their repertoire for probing hormone signalling, physiology and pesticide mode of action. These studies have led to the discovery of compounds that regulate development and the response to environmental stress. Chemical genetics facilitates our understanding of genetic signalling pathways and offers a new approach to pest management and plant health by enabling the direct chemical modulation of plant defence signalling. Copyright © 2007 Society of Chemical Industry
Determination of the pesticides considered as endocrine‐disrupting compounds (EDCs) by solid‐phase extraction followed by gas chromatography with electron capture and mass spectrometric detection
Authors: Valsamaki Vasiliki I. , Sakkas Vasilios A. , Albanis Triantafyllos A. 
Published: June 2007

AbstractAn SPE method followed by GC‐electron capture detection (ECD) with confirmation by MS for the trace determination of four pesticides considered as endocrine‐disrupting compounds (EDCs) in natural waters and sediments has been developed. Target analytes, fenarimol, fenvalerate, pendimethalin, and vinclozolin, belong to different chemical groups and are used mainly in agriculture. In the present study, analysis employs an offline SPE step for the extraction of the target analytes from natural waters. Sonication and subsequent SPE clean‐up was used for extraction and purification of the sediment samples which were finally treated with activated copper powder. The type of SPE disk, eluents as well as solution parameters including pH value, and concentrations of salts and humic substances were examined for the efficiency of the method. The recoveries of all pesticides were in relatively high levels, ranging from 75 to 97% for waters and 71 to 84% for sediment samples. Both methods were applied to real water and sediment samples and the presence of the tested compounds was investigated.
High‐performance liquid chromatographic separation of stereoisomers of N‐phthaloyl‐protected amino acids and dipeptidomimetics
Authors: Ilisz István , Ballet Steven , Van Rompaey Karolien , De Wachter Rien , Tourwé Dirk , Armstrong Daniel W. , Péter Antal 
Published: June 2007

AbstractThe stereoisomers of N‐phthaloyl‐protected amino acids and dipeptidomimetics were separated on macrocyclic glycopeptide and cellulose‐based chiral stationary phases (CSPs) in the RP and polar‐ionic modes. The effects of the organic modifier, the mobile phase composition, and the pH on the separations were investigated. Optimization of these separations was achieved through variation of the mobile‐phase additive combinations. The elution sequence was determined for some of the samples. A practical application for the monitoring of the reaction conditions for N‐phthaloylation of (S)‐Phe was demonstrated.
Application of a new zwitterionic hydrophilic interaction chromatography column for determination of paralytic shellfish poisoning toxins
Authors: Diener Marc , Erler Katrin , Christian Bernd , Luckas Bernd 
Published: June 2007

AbstractA novel method for paralytic shellfish poisoning (PSP) toxins which is based on the chromatographic separation of the toxins using a zwitterionic (ZIC) hydrophilic interaction chromatography (HILIC) column is presented. Efficient retention of the polar PSP toxins on the ZIC‐HILIC column allowed their selective and sensitive determination by the application of mass spectrometric (MS/MS) detection or as derivatives after oxidation prior to fluorescence detection (FD). Low buffer concentrations and the omission of ion‐pair reagents decreased the limits of detection (LODs) by MS/MS analysis and showed a good linearity for both methods of detection. This method can be applied for the qualitative and quantitative determination of PSP toxins in various types of phytoplankton, and for the routine analysis of seafood.
Proteomic approach for purification of seminal plasma proteins involved in tumor proliferation
Authors: Hassan Md Imtaiyaz , Kumar Vijay , Kashav Tara , Alam Neelima , Singh Tej P. , Yadav Savita 
Published: June 2007

AbstractHuman seminal plasma contains a large array of proteins required for the normal physiology and metabolism of spermatozoa. These are mainly secreted from prostate epithelium, testes, and seminal vesicles. Fortunately, many of these are found to be present at elevated concentration in seminal plasma and act as a biomarker of different carcinomas as their levels are also enhanced in serum and are found to be involved in tumor progression and metastasis apart from fertility. The proteins which were overexpressed in the seminal plasma of prostate carcinoma patients were identified by 2‐DE and MALDI‐TOF/MS. We have designed a strategy to purify these four proteins prostate specific antigen (PSA), prostatic acid phosphatase (PAP), Zinc α2‐glycoprotein (ZAG), and progastricsin (PG), together in homogeneity by using simple chromatographic techniques. Acidic and basic fractions of human seminal plasma were separated by ion exchange chromatography and further purified by gel permeation chromatography. Our results form a new and valuable resource for those attempting structure‐based drug designing for prostate and other cancers where the amount of proteins is required in plenty and in native form.
Recent developments in the high‐performance chelation ion chromatography of trace metals
Authors: Nesterenko Pavel N. , Jones Phil 
Published: June 2007

AbstractThere have been a number of significant developments in the high‐performance chelation ion chromatography (HPCIC) of trace metals in recent years. This review focuses on these developments, while giving important information on the fundamental parameters controlling the chelation sorption mechanism, including type of chelating group, stability constants, kinetics, and column temperature. The discussion pays particular attention to the types and properties of efficient chelating stationary phases which have been fabricated for certain groups of metals. The review also describes a number of major improvements in postcolumn reaction detection including the use of the latest reagents and noise reduction strategies to improve sensitivity and reduce LOD. In the final section, an indication of the applicability of HPCIC to a range of complex sample types is given with some key examples and chromatograms using the latest high‐efficiency chelating phases.
Microtomographic analysis of healing of femtosecond laser bone calvarial wounds compared to mechanical instruments in mice with and without application of BMP‐7
Authors: Girard B. , Cloutier M. , Wilson D.J. , Clokie C.M.L. , Miller R.J.D. , Wilson B.C. 
Published: June 2007

AbstractBackground and ObjectiveThis study investigated the healing of femtosecond laser created wounds in an animal model.Study DesignWe have assessed the healing of critical size wounds in mice calvaria using three different wounding techniques: carbide bur, diamond end‐cutting bur, and ultrafast femtosecond laser, and in the presence or absence of bone morphogenetic protein‐7 (BMP). Wound closure was examined using microcomputerized tomography at 3, 6, 9, and 12 weeks.ResultsResults have shown partial closure at up to 12 weeks with all techniques that did not involve the use of BMP, with the least closure noted in the laser groups as suggested by two‐dimensional radiographic analysis. Bone volume measurements appeared slightly lower for the laser than for the mechanical groups, however statistically significant differences were seen only at week 6. No significant differences in closure were noted for the different methods in the BMP treated groups.ConclusionsFemtosecond laser cutting demonstrated an unsurpassed precision when compared to mechanical instruments. The addition of BMP led to very rapid healing with complete closure seen as early as 3 weeks and overcomes any potential healing delays that may arise from laser tissue cutting. Lasers Surg. Med. 39:458–467, 2007. © 2007 Wiley‐Liss, Inc.