bluuebunny/crossref_metadata_2025 huggingface dataset:
Bifunctional homopolymeric hydrogen‐bonded tapes
Authors: Ashton Peter R. , Brown George R. , Hayes Wayne , Menzer Stephan , Philp Douglas , Stoddart J. Fraser , Williams David J.
Published: May 2005

A novel cationic homopolymeric system has been constructed from a simple linear cationic pyridylphyridinium system by forming hydrogen bonds between the carboxylic acid termini of one molecule and the pyridine nitrogen atom of an adjacent molecule. The synthesis and characterization of the initial linear system are described and the X‐ray crystal structure of the final tape system presented. This work illustrates how molecular recognition can be utilized to assemble supramolecular structures with a degree of predictability.
A luminescent iridium(III) cyclometallated complex immobilized in a polymeric matrix as a solid‐state oxygen sensor
Authors: Di Marco Gaetano , Lanza Maurizio , Pieruccini Marco , Campagna Sebastiano
Published: May 2005

In luminescence‐based oxygen sensors the active luminescent species is usually a transition metal complex immobilized in a polymeric matrix—in most cases a ruthenium(II) polypyridine complex. In an attempt to overcome some of the disadvantages of these systems, a polymer‐immobilized iridium(III) complex has been prepared and used for the first time as the active species in such a sensor. The luminescence properties of this system are described and its drawbacks with regard to sensors technology discussed.
Kinetics of metallocene intercalation into layered metal dichalcogenide hosts
Authors: Price Stephen J. , Evans John S. O. , Francis Robin J. , O'Hare Dermot
Published: May 2005

Intercalation into lamellar host lattices is in general poorly understood with regard to mechanistic details. A study is reported here that utilizes energy dispersive X‐ray diffraction at a synchrotron source to determine the rate of intercalation of cobaltocene into a range of lamellar metal dichalcogenide lattices. The results are suggested to have general implications for how metallocene intercalation into metal dichalcogenides should be performed in order to maximize the rate of reaction.
Crystal growth and characterization of the organic salt 4‐N, N‐dimethylamino‐4′‐N‐methyl‐stilbazolium tosylate (dast)
Authors: Pan Feng , Wong Man Shing , Bosshard Christian , Günter Peter
Published: May 2005

The growth of bulk crystals of organic salts with large chromophoric has received little attention, despite the importance of crystal quality for both applications and research. Here, the growth of the title compound (DAST), see Figure, is reported and the main results of the linear, nonlinear, and electro‐optical characterization are presented DAST is shown to be of interest for nonlinear optical applications.

magnified image
Donor‐Linked Fullerenes: Photoinduced electron transfer and its potential application
Authors: Imahori Hiroshi , Sakata Yoshiteru
Published: May 2005

Redox‐active fullerenes can be covalently bound to a variety of donors, their photophysical properties have been investigated. Their photochemical processes. Including electron transfer and energy transfer, are varied, depending on the donor, linkage between the donor and C60, and solvent. Regardless of the solvent and linkage, the charge‐separated state is produced efficiently in zinc porphyrin‐C60 systems, showing that C6o is a good electron acceptor. The most intriguing characteristic of C60 in electron transfer is that C60 accelerates photoinduced charge separation and retards charge recombination in the dark. The long‐lived charge‐transfer state: of the C60–porphyrin dyad was successfully converted to photocurrent using a self‐assembled monolayer technique. These findings will provide a new strategy for the design and synthesis of artificial photosynthetic systems and photoactive materials using C60 as a building block.
Spectral narrowing in optically pumped poly (p‐phenylenevinylene) Films
Authors: Friend Richard H. , Denton Graham J. , Tessler Nir , Stevens Mark A.
Published: May 2005

Lasing in conjugated polymer thin films? Not so, according to the results presented here. As previously reported, for films of a variety of conjugated polymers on glass substrates the emission spectrum narrows with increasing optical‐pump intensity when pulsed excitation is used. A detailed study is described here of this spectral narrowing phenomenon using films of poly(p‐phenylenevinylene) (PPV). Evidence is presented that weakens the case for lasing being the mechanism involved and supports and supports amplification of spontaneous emission by waveguiding.
Phototropic discrimination of the polymerization behavior of diacetylene Langmuir–Blodgett films by an azobenzene‐containing monolayer
Authors: Seki Takahiro , Tanaka Keisuke , Ichimura Kunihiro
Published: May 2005

Modulation of the photopolymerization behavior of a diacetylene Langmuir–Blodgett film by means of a control azobenzene‐containing monolayer is reported. It is shown that the color change resulting from the photopolymerization of the diacetylenic overlayer is affected by secondary changes depending on the isomerization state of the azobenzene surface beneath the overlayer. Extensions of the process may eventually be useful as a new tool for the fabrication of displays and organic devices in optics and optoelectronics.
The UK research assessment exercise
Authors: Harris Jack
Published: May 2005

In the Research Assessment Exercise, carried out roughly every four years, each university department in the UK is given a “mark” according to research performance. In the recently announced 1996 results, the materials science and metallurgy departments did extraordinarily well, five scoring the top mark (5). A compilation of the results is presented.
Synthesis of cellular inorganic films from self‐organized Media
Authors: Walsh Dominic , Mann Stephen
Published: May 2005

Cellular and honeycomb structures of inorganic materials are of interest for applications requiring, e.g., catalyst supports or heat‐resistant membranes. The synthesis fo cellular films from solvent‐extracted metal‐ion‐containing microemulsions (the Figure shows a resulting hollow spherical shell of calcium carbonate) is extended here to FeIII, MnIII/IV, and CoIII oxides. The preparation is detailed and the mechanism of formation discussed.

magnified image
Highly ordered polymer–inorganic nanocomposites via monomer self assembly: In situ condensation approach
Authors: Gray David H. , Hu Sanlin , Juuang Elizabeth , Gin Douglas L.
Published: May 2005

A highly ordered organic inorganic nanocomposite can be synthesized by photopolymerizing an inverse hexagonal lyotropic liquid crystal phase consisting of an amphiphilic monomer and organic crosslinker as the organic matrix and a sol‐gel silica precursor solution as the hydrophilic component (see Figure). In situ silica condensation gives the ordered nanocomposite. A simple example is discussed.

magnified image
Controlling electronic properties of CdTe by adsorption of dicarboxylic acid derivatives: Relating molecular parameters to band bending and electron affinity changes
Authors: Cohen Rami , Bastide Stéphane , Cahen David , Libman Jacqueline , Shanzer Abraham , Rosenwaks Yossi
Published: May 2005

Surface modifications have great potential to control semiconductor properties such as band bending (BB) and electron affinity (EA). It is demonstrated that tailor‐made, surface‐binding molecules—discarboxylic acid derivatives with aromatic substituents in this case—can be used to modify systematically both the EA and BB of CdSe. The molecular parameters that affect each of these have been resolved and a semiquantitative model is put forward to rationalize the observed molecule‐induced band‐bending energies.
Spatially functionalized polymer surfaces produced via cell‐mediated lithography
Authors: Alexander Cameron , Vulfson Evgeny N.
Published: May 2005

Cell‐mediated lithography—which generates polymer particles with anisotropic patches of addressable functionality of exactly the same size and shape as the template microorganism—is described. The Figure shows the first step in the process. Similarities with lithography using self‐assembled monolayers of alkane‐thiolates on gold substrates are pointed out and some of the many practical applications indicated.

magnified image
Creation of thermo‐responsive ion‐track membranes
Authors: Yoshida Masaru , Asano Masaharu , Suwa Takeshi , Reber Nicole , Spohr Reimar , Katakai Ryoichi
Published: May 2005

Temperature‐responsive membranes have been produced by combining ion‐track membranes with a temperature‐responsive hydrogel, which swells and absorbs water below 14°C, releasing it and shrinking above this temperature. The preparation of the ion‐track membranes is described and how the polymer hydrogel is grafted onto the surfaces of the membrane and the walls of the cylindrical pores (formed by the etched ion tracks). An investigation of between fully open and fully closed pores at different temperatures.
An enhanced chemiluminescent enzyme immunoassay for serum carcinoembryonic antigen based on a modification of a commercial kit
Authors: Haggart R. , Thorpe G. H. G. , Moseley S. B. , Kricka L. J. , Whitehead T. P.
Published: May 2005

A conventional colorimetric peroxidase end‐point (ortho‐phenylenediamine substrate), used in an enzyme immunoassay for carcinoembryonic antigen, employing plastic beads as solid support, has been replaced by a much faster (30 seconds versus 30 minutes) enhanced chemiluminescent assay for the peroxidase label. Para‐iodophenol was used to enhance the light emission from the peroxidase catalysed chemiluminescent reaction between luminol and hydrogen peroxide. Values for precision and carcinoembryonic antigen concentration obtained with the chemiluminescent and colorimetric versions of the immunoassay on 62 serum specimens were in good agreement.
Luminol dependent chemiluminescence and thiol group oxidation provoked by neutrophils is attributable to different oxidizing species
Authors: Jenner David E. , Holt Mary E. , Campbell Anthony K.
Published: May 2005

Luminol‐dependent chemiluminescence and thiol group oxidation of glutathione and human serum albumin were measured in order to demonstrate whether the inhibition of polymorphonuclear leukocyte chemiluminescence by albumin was attributable to thiol group oxidation. We have shown that:

thiol groups on glutathione and albumin are oxidized by PMNL stimulated by soluble and phagocytic stimuli;

thiol group oxidation in albumin and glutathione did not correlate with the inhibitory effects of these substances on luminol‐dependent chemiluminescence with respect to time course, magnitude, effects of known scavengers or extracellular activity. It was therefore concluded that thiol group oxidation was not the cause of albumin inhibition of luminol‐dependent chemiluminescence;

a metastable oxidant was identified after PMNL activation which was capable of oxidizing thiol groups but unable to elicit chemiluminescence form luminol.
Dyakia bioluminescence—1. Bioluminescence and fluorescence spectra of the land snail, D. striata
Authors: Isobe Minoru , Uyakul Duangchan , Goto Toshio , Counsilman James J.
Published: May 2005

The luminescent land snail Dyakia striata displayed a bioluminescence spectrum with a maximum wavelength of 515 nm. A green fluorescent substance extracted from the photogenic organ of an adult snail had a similar wavelength maximum but its fluorescence spectrum differed from that of flavin chromophore substances involved in light emission in some other luminescent organisms.
Effect of surfactants on the intensity of chemiluminescence emission from acridinium ester labelled proteins
Authors: Bagazgoitia F. Javier , Garcia J. Luis , Diéquez Carlos , Weeks Ian , Woodhead J. Stuart
Published: May 2005

In order to establish optimum conditions for the chemiluminescent (CL) reaction of two acridinium ester labelled proteins (human albumin and rabbit anti‐human albumin IgG), we investigated the effects of the following factors known to influence the CL emission: pH, presence of proteins, relative concentrations of components of CL reaction and presence of surfactants. Under optimal conditions of pH and hydrogen peroxide concentration, hexadecyl trimethyl ammonium chloride (CTAC) increased the intensity of the CL reaction of the acridinium ester labelled albumin by 42‐fold. Triton X‐100, Tween‐20, 23 lauryl ether (Brij 35) and sodium dodecyl sulphate (SDS) exerted a much smaller effect. In the case of the acridinium ester labelled antibody, the greatest increase was obtained with Triton X‐100 (15‐fold) followed by CTAC, Brij 35 and Tween 20 (SDS decreased the emission intensity).
Long‐term preservation of active luminous bacteria by lyophilization
Authors: Janda Ivan , Opekarová Miroslava
Published: May 2005

A simple method for long‐term preservation of luminous bacteria is described. Cells of Vibrio fischeri, Photobacterium leiognathi and four strains of P. phosphoreum were suspended in a protective medium of low ionic strength (1% NaCI) supplemented with 15% lactose and 2% soluble starch, and lyophilized. The freeze‐dried preparations were sealed under vacuum and stored at 4°C. Luminous bacteria were resuscitated affer six months by adding 2% NaCl up to the original volume. The rehydrated cells exhibited 16‐28% of initial bioluminescence so that they could be used for a microbial test of toxicity (the Microtox test). This method is also useful for maintaining luminous bacteria in strain collections.
Use of a microtitre plate chemiluminescence reader to study surface phagocytosis by human monocytes
Authors: Cree Ian A. , Blair Andrea L. , Beck J. Swanson
Published: May 2005

Human mononuclear cells were separated from freshly obtained peripheral venous blood by density centrifugation and the number of monocytes present estimated by volume spectroscopy. The mononuclear cells were then placed directly into the wells of a microtitre plate and incubated for one hour at 37°C to promote adherence of the monocytes to the plastic wells. Non‐adherent cells were then removed by washing, thus avoiding the need to treat the monocytes with EDTA or other reagents during cell preparation. The time course and dynamics of the chemiluminescence response of adherent monocytes towards opsonized zymosan was similar to those seen using non‐adherent cells.

The ability of adherent monocyte preparations to produce chemiluminescence following incubation for varying periods with T‐lymphocyte conditioned medium was investigated. The use of a microtitre plate chemiluminescence reader allows several plates to be assayed over the 24‐hour period and since small numbers of cells are required, many cultures can be analysed in one experiment. This technique (Patent applied for) promises to be a powerful tool for dissecting the cellular events which occur during macrophage activation and examining the effect of various lymphokines on the ability of monocytes to produce a chemiluminescence response.
Effect of a new fluorinated quinolone (ofloxacin) on the chemiluminescence of phagocytosing human neutrophils
Authors: Aquilini Donatella , Bartoloni Alessandro , Paradisi Franco
Published: May 2005

We measured the chemiluminescence (CL) of human neutrophils (PMNLs) exposed to different concentrations of ofloxacin (2, 4, and 6 μg/ml) readily achievable in therapy. CL reaction during zymosan phagocytosis by PMNLs obtained from human healthy volunteers was registered in a computer‐linked LKB 1251 luminometer. Ofloxacin did not induce significant variations on the respiratory burst of PMNLs.
Opsonic activity of ascitic fluids by a chemiluminescent method
Authors: Huu T. R. Pham , Bendahou M. , Sourbier P. , Mal F. , Beaugrand M. , Hakim J.
Published: May 2005

Cirrhotic ascites are highly susceptible to spontaneous bacterial infection, whereas carcinogenic ascites are seldom infected. This difference may be explained by differences in their chemotactic, bactericidal and/or opsomic activities. We measured the chemotactic and opsonic activity of ascitic fluids from 35 alcoholic cirrhotic ascites and of 12 peritoneal carcinogenic ascites. Chemotactic activity was measured by the under‐agarose technique and opsonic activity by a luminol‐enhanced method. Ascitic fluids from alcoholic cirrhosis had low chemotactic (62 ± 24.5% that of N‐formylated peptide) and opsonic (67 ± 50% of normal serum) activities on normal human neutrophils. In contrast, ascitic fluids from peritoneal carcinoma were found to possess high opsonic activity (114 ± 49% of normal serum) and chemotactic activity similar to that of N‐formylated peptide. During a 3‐month follow‐up, 11 spontaneous bacterial infections were observed among the first group against none in the carcinogenic group.
Bioluminescent assay of bacterial ATP for rapid detection of bacterial growth in clinical blood cultures
Authors: Nilsson L. E. , Molin Ö. , Ånséhn S.
Published: May 2005

A bioluminescent assay of bacterial ATP for rapid detection of bacterial growth in 512 clinical aerobic blood cultures was evaluated. At the detection limit of bacterial ATP (10−10 mol/l) in the blood cultures 94.2% of the true positive blood cultures were detected (sensitivity) and the specificity was 85.8%. If the cut‐off limit was increased the sensitivity decreased and the specificity increased and at 2 × 10−9 mol/l ATP the maximum correctly classified blood cultures was reached. At this cut‐off limit the sensitivity was 82.9% and the specificity was 99.6%. In 54.3% of the true positive blood cultures bacterial growth was detected more rapidly with the bioluminescent assay than with macroscopic examination and subculture.
An evaluation of the performance of ten commercial luminometers
Authors: Jago P. H. , Simpson W. J. , Denyer S. P. , Evans A. W. , Griffiths M. W. , Hammond J. R. M. , Ingram T. P. , Lacey R. F. , Macey N. W. , McCarthy B. J. , Salusbury T. T. , Senior P. S. , Sidorowicz S. , Smither R. , Stanfield G. , Stanley P. E.
Published: May 2005

An assessment has been carried out of the relative performance of ten instruments for quantification of adenosine triphosphate (ATP) by the firefly luciferase assay. The instruments evaluated were Amersham Amerlite Analyser, Dynatech Tube Luminometer, Dynatech Multiplate Luminometer, Dynatech Camera Luminometer, Hamilton Lumicon, LKB 1250 Luminometer, LKB 1251 Luminometer, Lumac Biocounter M2010A, Turner 20 TD Luminometer and a prototype version of the CLEAR Speed Tech 2000. An 800‐fold difference in sensitivity was found between the most sensitive (Lumac, Turner) and the least sensitive (Dynatech Tube) of the conventional instruments. The Dynatech Camera Luminometer which worked on a completely different principle to the other instruments was about 5000 times less sensitive than the best of the photomultiplier tube instruments. The relative sensitivity of the instruments was maintained regardless of whether solutions of ATP in water or trichloroacetic acid extracts of bacteria were analysed. An analysis of 960 ATP bioluminescence assays showed that data obtained from such measurements are normally distributed.
Method for reducing the rate of light emission from chemiluminescent and bioluminescent reactions using frozen reagents
Authors: Kricka Larry J. , Ogden Susan , Williams Thomas M. , Kant Jeffrey
Published: May 2005

Frozen assay reagents have been used to reduce the rate of light emission from the rapid chemiluminescent acridinium ester and the bioluminescent firefly luciferase reactions. Melting of the assay reagent delays the initiation of the light emission, thus eliminating the need to initiate these rapid reactions by injection of the assay reagents in front of the photodetector.
Organization of the lux genes of photobacterium phosphoreum
Authors: Mancini J. , Boylan M. , Soly R. , Ferri S. , Szittner R. , Meighen E.
Published: May 2005

The lux genes from Photobacterium phosphoreum (NCMB844) have been cloned into Escherichia coli in a plasmid containing the T7‐bacteriophage promoter. By specific expression in vivo under the T7 promoter, five structural genes (luxA‐E) coding for the fatty acid reductase and luciferase polypeptides were identified as well as a new gene, designated as luxF, which codes for a 26kDa polypeptide. This new gene is located between luxB and luxE and thus disrupts the structural gene order of luxCDABE found in the Vibrio genus. The luxF gene and the protein it codes for have recently been identified in other Photobacterium species and so appears to be widely distributed within this genus. Nucleotide sequencing of the luxF gene has shown it to code for a protein homologous to the luciferase subunits, coded by the luxA and luxB genes. Although this gene is not necessary for light emission in all luminescent bacteria, it must play an essential role in the biochemistry, physiology, or ecology of the luminescent system in species of the Photobacterium genus.
Chemiluminescent labelled streptavidin (STAV) as a universal marker in steroid and peptide immunoassays
Authors: Strasburger C. J. , Kohen F.
Published: May 2005

The tetrameric structure of streptavidin and its exceptionally strong affinity to biotin (Ka = 1015M−1) can be exploited to achieve an amplification of the signal in immunoassays. In the approach described here streptavidin (STAV) labelled with aminobutylethyl‐isoluminol (ABEI) served as a universal marker in immunoassays for both haptens and big antigens. The advantageous features of streptavidin can be applied to any immunoassay using biotinylated antibodies as the primary probe.

In two‐site immunometric assays for larger antigens the liquid phase ‘tracer’ antibody is biotinylated. In hapten assays the solid phase antigen technique (Wood et al., 1982) is employed, in which sample‐antigen and solid phase‐antigen compete for a biotinylated antibody. In this paper we demonstrate the use of STAV–ABEI as a universal chemiluminescent label in steroid assays and in an immunometric assay using human growth hormone (hGH) as an example.
Characteristics and detection principles of a new enzyme label producing a long‐term chemiluminescent signal
Authors: Jansen Eugène H. J. M. , van den Berg Rijk H. , Zomer Gijsbert
Published: May 2005

A new enzyme label system is described which is superior to all existing chemiluminescence labels used in immunoassays. The system consists of the enzyme xanthine oxidase with hypoxanthine as substrate. The signal reagent contains perborate, an Fe–EDTA complex and luminol. The enzyme preparation and the signal reagent are very stable upon storage. The main features of the system are a long duration of the chemiluminescent signal (half‐life time of 30 hours) and a very low limit of detection (about 3 amol). Possibilities and implications for the use of various measuring system are discussed.
Discrimination between different types of low‐level luminescence in mammalian cells: The biophysical radiation
Authors: Reiber H.
Published: May 2005

Cellular low‐level luminescence was measured after various disintegrative processes in brain cell preparations. In addition to known origins of low‐level luminescence, e.g. oxygen radical reactions or enzymatic and non‐enzymatic redox systems, a further source of photon emission is reported which is independent of external oxygen, oxygen radicals and enzyme activities.

Vital cells from rat brain homogenates or pig oligodendrocytes could be kept for hours at 37 °C without any photon emission. Only after disintegrative processes a cellular photon emission could be induced. The maximal intensity of about 400 impulses/s/mg protein and a total radiation of about 6 × 106 I/mg depended on the type of cells. The signal could be retained completely at 4 °C or in frozen samples. Heating (10 min, 90 °C) did not suppress the photon emission. Luminol and lucigenin did not amplify the signal as is usually observed in oxygen radical‐producing cells. Non‐specific radical scavengers as well as detergents suppressed the cellular photon emission completely. It is suggested that this cellular luminescence represents a biophysical radiation which originates from the interruption of an intermolecular radiationless energy transfer.
Use of bioluminescence in nucleic acid hybridization reactions
Authors: Balaguer Patrick , Térouanne Béatrice , Boussioux Anne‐Marie , Nicolas Jean‐Claude
Published: May 2005

Luminescence reactions can be used to detect specific nucleic acid sequences hybridized with a nucleic probe. Different labels such as cytidine sulphone, fluorescein, and biotin can be incorporated into DNA or oligonucleotide molecules and detected by antibody or avidin conjugates coupled to glucose‐6P dehydrogenase.

On supports such as nitrocellulose filters, sensitivity is not greatly increased using luminescence, but detection is rapid and easy to perform using polaroid film. Moreover, hybridization can be performed with different labelled probes on the same sample.

In solution, luminescence can be used to monitor sandwich reactions. The method is less sensitive than detection on filters but can easily be automated. The performance of these assays can be increased considerably by enzymatic amplification of the target catalysed by a thermostable polymerase.
The complete nucleotide sequence of the lux regulon of Vibrio fischeri and the luxABN region of Photobacterium leiognathi and the mechanism of control of bacterial bioluminescence
Authors: Baldwin T. O. , Devine J. H. , Heckel R. C. , Lin J.‐W. , Shadel G. S.
Published: May 2005

We have determined the complete nucleotide sequence of a 7622 base pair fragment of DNA from Vibrio fischeri strain ATCC7744 that contains all the information required to confer plasmid‐borne, regulated bioluminescence upon strains of Escherichia coli. The lux regulon from V. fischeri consists of two divergently transcribed operons, L (left) and R (right), and at least seven genes, luxR (L operon) and luxICDABE (R operon) and the intervening control region. The luxA and luxB genes encode respectively the α and β subunits of luciferase. The gene order luxCDABE seen in V. fischeri is the same as for V. harveyi. We have determined the sequence of the luxAB and flanking regions from Photobacterium leiognathi and have found upstream sequences homologous with luxC from the Vibrio species, but between luxB and luxE, there is an open reading frame encoding a protein of 227 amino acids (26,229 molecular weight) that is not found in this location in the Vibrio species. The amino terminal amino acid sequence of the encoded protein is nearly identical to that determined by O'Kane and Lee (University of Georgia) for the non‐fluorescent flavoprotein from a closely related Photobacterium species (Dr Dennis O'Kane, personal communication). We have therefore designated this gene luxN.

There is a 20‐base inverted repeat ACCTGTAGGA×TCGTACAGGT, centred between bases 927 and 928 in the region between the two operons of V. fischeri. This region appears to fulfil two functions: it is critical for the LuxR protein to exert its effect and it is a consensus binding site for the E. coli LexA protein, a negative regulatory protein involved with the SOS response. There are sequences within the luxR coding region that appear to function in a cis‐acting fashion to repress transcription from both the leftward and rightward promoters in the absence of the respective transcriptional activator proteins, thereby resulting in low basal levels of transcription. It now appears clear that there are multiple levels of control on the lux system allowing for a modulation of the intensity of bioluminescence of over four orders of magnitude.
Acridinium ester‐labelled DNA oligonucleotide probes
Authors: Septak M.
Published: May 2005

Chemiluminescent acridinium ester derivatives have been synthesized and covalently attached to suitably modified synthetic DNA oligonucleotides. Attachment of acridinium ester label to primary aliphatic amine group(s) present in the synthetic DNA probe molecule is rapid and efficient. Methods have been developed for efficient separation of acridinium ester‐labelled DNA from unincorporated labelling reagent and underivatized DNA.

The basic hydrogen peroxide detection reaction and photon counting conditions for measurement of chemiluminescence emission from acridinium ester‐labelled DNA probes have been optimized. Under optimal conditions, the observed detection limit for the labelled DNA (1:1 mole ratio) is the same as for the free acridinium ester label, which is 2 attomole sensitivity in the best case studied.
Single photon counting imagery
Authors: Scott R. Q. , Inaba Humio
Published: May 2005

Advent of the multichannel plate and position sensitive detector has made possible true single photon counting imaging tubes. We have investigated the application of these detectors in studies of the ultraweak light emission of biological materials. Initially, we focussed our efforts on two objectives: (1) obtaining single photon counting images of living tissues using only the light (chemiluminescence) emitted by the specimen and (2) developing means of obtaining well‐resolved spectra of weakly emitting sources. We have obtained a variety of images. One striking result of this work is the first observation of tissue specific localization of photon emission in situ. Using this detector we have also obtained the first well‐resolved spectra of some important ultraweak emission processes. These results illustrate the potential use of single photon imaging in bioluminescence and chemiluminescence research.
A chemiluminescence automatic analyser for the measurement of biological compounds
Authors: Tabata Masayoshi , Totani Masayuki , Murachi Takashi
Published: May 2005

A compact automated analyser which could analyse constituents in biological fluids with a small sample volume and in a short time has been developed. The instrument was composed of a flow injection analysis system equipped with chemiluminometric detection and an immobilized enzyme column reactor used in combination. Chemiluminescence has high sensitivity, and its reaction proceeds very quickly. Furthermore, an immobilized enzyme column reactor can produce a sufficient amount of hydrogen peroxide from compounds in serum in a short time. When enzymes are used as reagents for the analysis of substances in blood or blood serum, the final signals emitted by different enzyme reactions are usually not only hydrogen peroxide but also ammonia, NAD(P)H and so on. However, the practical chemiluminescence method for ammonia and NAD(P)H has not been established. We have discovered a new practical method for ammonia and NAD(P)H using an enzyme column reactor consisting of both immobilized L‐glutamate dehydrogenase and L‐glutamate oxidase. The determinations of glucose and uric acid in serum by chemiluminometry after production of hydrogen peroxide by the respective oxidases are presented. A newly chemiluminometric determination of ammonia, NAD(P)H and its applications to other enzymatic analyses that give ammonia and NAD(P)H as a final signal are also described.
Configuration and optimization of a common two‐site immunoassay for human prolactin using a chemiluminescent tracer and an enzymatic tracer
Authors: Farina L. , Comuzio S. , Bolelli G. , Mimmi P. , Messeri G. , Orlandini A.
Published: May 2005

We have developed a two‐site immunoassay for human prolactin using two monoclonal antibodies: one of them immobilized on the solid phase and the other labelled with biotin. The serum is incubated simultaneously with the antibody‐coated bead, the biotinylated antibody and the tracer (streptavidin–isoluminol or avidin–peroxidase complex). Our experimental work has been directed towards a common set of reagents to capture the prolactin and then, with different tracers, towards obtaining on the calibration curve the same results for unknown samples.

On the basis of the positive results we obtained, we have developed a kit that can be used by the customer or as an enzyme‐immunoassay or as a chemiluminescent immunoassay, depending on instrumentation available, spectrophotometer or luminometer.
Future applications of magic lite technology
Authors: Krodel Elizabeth , Unger John
Published: May 2005

The features that Magic Lite products offer as an immunoassay delivery system are discussed. The use of paramagnetic particles and acridinium ester labels confers advantages of speed, sensitivity, and stability. The technology has been used to measure analytes of widely varying molecular weights and serum concentrations, indicating its potential to detect the full range of clinically relevant analytes. Initial development efforts have indicated that the advantages of the system can be effectively exploited in an automated instrument.
Magnesium‐dependent induction of phagocytosis‐associated chemiluminescence of adherent human polymorphonuclear leukocytes by non‐opsonized zymosan
Authors: Roschger Paul , Graninger Wolfgang , Klima Herbert
Published: May 2005

A severe dysfunction in the cellular response of human polymorphonuclear leukocytes (PMNL) to non‐opsonized zymosan was observed under a deficiency of extracellular Mg2+. The phagocytosis‐association native (luminol‐independent) luminescence (NL), as well as luminol‐dependent luminescence (LDL) (detected simultaneously and discriminated by spectral methods), was strongely inhibited. Apart from a general decrease of total light production, a Mg2+‐concentration‐dependent delay of the maximum of NL and LDL was observed. A disorder in recruitment of activated membrane‐bound NADPH‐oxidase of PMNL is suggested. The presence of extracellular Ca2+ did not compensate for the Mg2+ deficit. In the presence of Mg2+ only a slight Ca2+‐dependent reduction of NL was obtained, but Ca2+ seemed to selectively promote LDL. This may indicate a positive influence of Ca2+ on the myeloperoxidase release from the cells. Experiments with the metalions‐chelating agents EDTA and EGTA, which complex Mg2+ to differing extents, confirmed the important role of Mg2+ in PMNL‐activation by non‐opsonized zymosan.
Enhanced chemiluminescent immunoassay for aldosterone
Authors: Hubl W. , Thorpe G. H. G. , Hofmann F. , Meissner D. , Thiele H. J.
Published: May 2005

A solid phase immunoassay for aldosterone using enhanced chemiluminescent detection has been developed. Monoclonal antibodies against aldosterone were used for the immune reaction and compared with polyclonal antibodies. Uniform Protein A coated polystyrene tubes were used as solid phase for the monoclonal antibody and second (anti‐rabbit) antibody coated tubes for the polyclonal antibody. Horseradish peroxidase was covalently linked to aldosterone as enzyme label. Optimum conditions were established for the generation and measurement of the luminescent reactions using luminol, p‐iodophenol as enhancer and hydrogen peroxide.

The advantages of this assay are the high sensitivity with a detection limit of 100fg/tube, the prolonged luminescence signal with a simplification of the measurement (simpler detectors, external start pipetting) and the short measure time with the possibility of repeated measurement. The coefficients of variation were 4.2%–7.3% in the concentration range 140–1180 pmol/l. The assay showed a significant correlation (r = 0.91) with the ELISA.

The aldosterone concentrations in plasma and saliva of patients with Conn's syndrome were significantly increased, and in patients with Addison's disease were found near the detection limit.
Influence of gluten‐derived fractions on chemiluminescence production by human neutrophils
Authors: Roccatello D. , Amprimo M. Claudia , Coppo Rosanna , Cavalli G. , Quattrocchio G. , Gianoglio B. , Ferrerc A. , Mauro Clelia Di , Sena L. M. , Piccoli G.
Published: May 2005

The effects of gliadin and glyc‐gli on leukocyte chemiluminescence response were assessed in vitro. A dose‐dependent increase in chemiluminescence response of neutrophils stimulated by zymosan was observed by using gliadin at concentrations ranging between 1 and 20 μg. By increasing glyc‐gli concentration, a bimodal response was observed with an enhancement up to 50 μg/ml, followed by suppressive effects, which were again dose‐dependent. The possible implications of these findings in human pathology are discussed.
Enhanced chemiluminescence ELISA for Listeria specific antigen in cerebrospinal fluid using an FITC‐anti‐FITC system
Authors: Samuel Dhanraj , McLauchlin James , Taylor Anthony G.
Published: May 2005

An enzyme‐linked immunosorbent assay (ELISA) is described for the detection of a soluble Listeria monocytogenes serogroup 4 antigen in cerebrospinal fluid samples (CSFs). In the ELISA an anti‐Listeria monoclonal antibody, immobilized onto assay wells, was used to capture antigen from CSFs. the captured antigen was then reacted with a fluorescein isothiocyanate (FITC) conjugate of the same anti‐Listeria antibody, which was detected with a horseradish peroxidase conjugate of a monoclonal antibody to FITC. The presence of antigen was detected by an enhanced chemiluminescence assay using a camera luminometer.

Antigen was detected in the CSFs taken from five out of seven patients with culture proven L. monocytogenes serogroup 4 central nervous system infections, and in none of the CSFs taken from 25 other patients.
Detection of Legionella pneumophila serogroup 1 urinary antigen using an enhanced chemiluminescence ELISA
Authors: Samuel Dhanraj , Harrison Timothy G. , Taylor Anthony G.
Published: May 2005

An enhanced chemiluminescence enzyme‐linked immunosorbent assay has been developed for the detection of soluble antigen in the urine of patients with Legionnaires' disease (LD). In the assay antigen(s) in the urine samples are captured by a rabbit anti‐L. pneumophila antibody coated onto microtitre strips. A fluorescein‐isothiocyanate (FITC) conjugate of the same antibody is then added which binds to the captured antigen. Any immobilized FITC‐labelled antibody is then detected with a horseradish peroxidase (HRP) conjugate of a monoclonal anti‐FITC antibody. HRP activity is monitored after oxidation of luminol in the presence of H2O2 and iodophenol. The resulting luminescence is recorded using a camera luminometer.

Urine specimens were available for testing from 31 patients with evidence of ongoing L. pneumophila serogroup 1 infection. A positive result was obtained in the cases of 12/12 specimens from culture‐proven LD patients, and 16/19 specimens from patients with serological evidence of LD. Thus the sensitivity is estimated to be 28/31 (90%) The specificity was estimated using urine specimens from eight patients with non‐L. pneumophila pneumonias of known aetiology. All eight specimens gave a negative result.
Affinity purification of bacterial luciferase and NAD(P)H:FMN oxidoreductases by FMN‐sepharose for analytical applications
Authors: Lavi Jukka T. , Raunio Raimo P. , Stahlberg Tom H.
Published: May 2005

A modified purification method for bacterial luciferases and NAD(P)H:FMN oxidoreductases is described which uses FMN‐Sepharose alone or coupled to DEAE ion exchange chromatography for the simultaneous purification of luciferase and the various oxidoreductases from Vibrio harveyi, a bright mutant of Vibrio harveyi, Vibrio fischeri, and Photobacterium phosphoreum. This purification method is compared with DEAE‐Sepharose CI 6B fractionations from these organisms. Both methods allow the separation of oxidoreductases specific for either NADH or NADPH. The use of FMN‐Sepharose coupled to DEAE‐Sepharose fractionation allows the isolation of highly purified enzymes. Lacking interfering factors, these are very suitable for various analytical applications based on bacterial bioluminescence enzymes. The partially purified enzymes from the affinity column have higher specific activities than those obtained using DEAE‐Sepharose.
Chemiluminescence of irradiated animal blood plasma
Authors: Kavetsky R. E. , Serkyz Ya. I. , Druzhina N. A. , Pinchouk V. G.
Published: May 2005

Spontaneous and induced chemiluminescence of rat blood plasma following irradiation of the animals with fast neurons was studied. Dynamics of the luminescence reflected the degree of radiation injury and an oscillatory response of blood chemiluminescent effect was observed.
Chemiluminescent reactions in the Belousov‐Zhabotinskii oscillating system
Authors: Zhuravlev A. I. , Trainin V. M.
Published: May 2005

Chemiluminescence (CL) occurs during reactions of several of the components of the CH2 (COOH)2KBrO3MnSO4H2SO4 self‐sustained system. In contrast to the kinetics determined using potentiometry and spectrophotometry, the CL intensity kinetic curve during the oxidation of manganese (II) ions by acidic bromate has an extremum. Experimental dependences of the maximum CL intensity value on the initial reagent concentrations have been determined and compared with the results of the numerical simulation based on the commonly accepted Noyes‐Field‐Thompson mechanism.
Three‐peaked chemilluminescent response of human peripheral blood leukocytes following stimulation with phytohaemagglutinin (PHA)
Authors: Warren N. , Jones A. E. , Bater A. J.
Published: May 2005

Luminol‐enhanced chemiluminescence (CL) was used to examine the response of various leukocyte populations following stimulation with a crude extract of Phaseolus vulgaris, namely phytohaemagglutinin (PHA‐C). Populations stimulated included a human peripheral mixed leukocyte preparation (MLP), and purified preparations of lymphocytes, monocytes and polymorphonuclear leukocytes (PMNL). Mouse peritoneal exudate cells and the lymphocytic cells lines Molt #4 and Daudi were also stimulated. Following stimulation, a characteristic three‐peaked chemiluminescent response was obtained from the MLP population. Little or no response was obtained from the purified lymphocytes. Monocytes produced a sharp peak corresponding to the second peak of the MLP response and PMNL produced a broad peak corresponding to the third peak of the MLP response. Mouse peritoneal exudate cells containing lymphocytes and monocytes/macrophages showed a two‐peaked stimulation which corresponded to the first two peaks of the MLP response. Molt #4 and Daudi showed no chemiluminescence if stimulated individually, but if added to a MLP substantial enhancement of the first and second peaks was observed. These results indicate some form of lymphocyte/monocyte interaction leading to enhanced CL following PHA‐C stimulation.
In memoriam Toshio Goto
Authors: Tsuji Akio
Published: May 2005

It was with great sadness that we received news of the sudden death on 29 August 1990 of Professor Toshio Goto who was a member of the Editorial Board of this Journal.
A luminometric method for the determination of ATP and phosphocreatine in single human skeletal muscle fibres
Authors: Wibom R. , Söderlund K. , Lundin A. , Hultman E.
Published: May 2005

A sensitive method for the analysis of ATP and phosphocreatine (PCr) in single human skeletal muscle fibres is described. Muscle tissue was freeze‐dried and single fibres were dissected free with the aid of low‐power microscopy. The fibres were then extracted in trichloroacetic acid and neutralized with KHCO3. The assay is based on the continuous monitoring of light produced as a result of ATP degradation in the firefly luciferase reaction. PCr is measured as the amount of ATP formed in the creatine kinase reaction. The coefficient of variation was less than 4% for both ATP and PCr determination. The amount of tissue required for the assay is approximately 0.5 μg (dry weight). The assay showed good agreement with spectrophotometric and high‐performance liquid chromatographic (HPLC) measurements made upon extracts of whole muscle tissue.
Bovine serum albumin interacts with bacterial luciferase
Authors: Makemson John C. , Hastings J. Woodland
Published: May 2005

Bovine serum albumin (BSA) affects the amount of light obtained from bacterial luciferase by competing with luciferase for one of the luciferase substrates, the aldehyde. At low aldehyde concentrations BSA behaves as an inhibitor, but at high aldehyde concentrations BSA relieves substrate inhibition. BSA reversibly binds decanal with a Ksi = 3.36 μmol/l, approximately half the affinity of luciferase for decanal (KM = 1.5 μmol/l). BSA also increased the rate of intermediate II dark decay. The data suggest that this involves a direct protein‐protein (BSA‐luciferase) interaction.
Differences in the respiratory burst of human polymorphonuclear leukocytes induced by virulent and avirulent Legionella pneumophila Serogroup 1
Authors: Rajagopalan‐Levasseur Premavathy , Dournon Eric , Vilde Jean‐Louis , Pocidalo Jean‐Jacques
Published: May 2005

Two strains of Legionella pneumophila of different virulence were examined for their influence on the metabolic oxidative activity of human polymorphonuclear leukocytes. The leukocytes exhibited decreased rates of oxygen consumption and diminished chemiluminescence activity following phagocytosis of a virulent strain of L. pneumophila serogroup 1. In contrast, phagocytosis of its multipassaged derivative rendered avirulent, was accompanied by increased rates of both oxygen consumption and chemiluminescence activity. Although no differences were observed in oxygen uptake induced by the virulent legionellae compared to leukocytes at rest, statistically significant differences were observed in the chemiluminescence responses. These observations were not unexpected, since the luminol‐enhanced chemiluminescence assay, is more sensitive than the oxygen uptake assay. In spite of decreased metabolic activity of PMN in the presence of virulent legionellae, electron microscope studies showed higher numbers of intracellular L. pneumophila than the avirulent subtype. Thus, virulent and avirulent L. pneumophila can be differentiated on the basis of oxygen consumption and chemiluminescence assays.
Leukocytes as immunosensors: An immunoassay without labelled reagents
Authors: Lilius Esa‐Matti , Kankaanpää Anne , Lahti Reijo
Published: May 2005

A novel quantitative nonlabel immunoassay is described. It is based on the recognition of antigen‐antibody complexes by the Fc‐receptors of phagocytic leukocytes and the subsequent activation of these cells. Activation which is proportional to the amount of immune complexes present can be detected by measuring the intensity of chemiluminescence emitted by the activated cells. In addition to determinations of an antigen and an antibody, the binding capacity of complement to antigen‐antibody complexes can be estimated.
Reactions of copper complexes with oxygen radicals generated by human neutrophils
Authors: Haseloff Reiner F. , Gruner Stefan , Wischnewsky Gerd G.
Published: May 2005

The intensity of the chemiluminescence of unstimulated human neutrophils in the presence of luminol was used to investigate the effects of low‐molecular‐weight copper complexes at the cellular level. In different models (superoxide dismutase mimetic activity, inhibition of haematoporphyrin derivative/light‐induced lysis of cells), the biological activity of the complexes exceeded the activity of the ligands alone.
Light‐induced biophotonic emission from plant tissues
Authors: Bajpai R. P. , Bajpai P. K.
Published: May 2005

The emission of biophotons in the visible range, following a delay time of 2‐200 seconds after exposure to light, has been measured in germinating seeds, roots, flowers, leaves, and cells. It was found that the biophotonic signals are reproducible and light‐induced. The observed signals from germinating seeds of Phaseolus aures and decaying leaves of Eucalyptus are presented to show that the signals have characteristic kinetics and intensity. The kinetics of the signal was found to be independent of the stage of growth or decay, though its intensity varied with biological factors. The kinetics in the first minute is characterized by a single exponential decay term while that in the region t ≤ 200 s is characterized by two exponentials. The variation in the intensity of the signal with mass, state of hydration, and growth, and the effect of inhibitors in various systems (e.g. leaves, lichen, Chlorella) are reported.