Fluorescent Whitening Agents Research Articles

Novel cotton cellulose by cationisation during the mercerisation process—part 1: chemical and morphological changes

Cationisation is the modification of cotton cellulose by using quaternary ammonium compounds that block negative OH groups, thus resulting in electropositive cotton cellulose. It is an alternative method for achieving better adsorption of chemical compounds and substances, such as dyestuffs, fluorescent whitening agents, and other textile auxiliaries. The cationisation of cotton cellulose changes the surface electrical charge (electrokinetic potential) by significantly increasing its adsorption properties. The presented article investigated the chemical and morphological changes in cotton cellulose when cationised with an epihalohydrin, 2,3-epoxypropyl trimethyl ammonium chloride, after and during the mercerisation process. When comparing mercerised cotton with cationised cotton, it was concluded that cationisation during the mercerisation process using short-chain cationic compounds would result in a novel cotton cellulose that would bring a new dimension to cotton pre-treatment and finishing. The modified cotton would retain all the beneficial properties of mercerised cotton with a change of surface charge that would ensure further improvement in quality.

Microscopy Observations of Habitable Space in Biochar for Colonization by Fungal Hyphae From Soil

Biochar is a potential micro-environment for soil microorganisms but evidence to support this suggestion is limited. We explored imaging techniques to visualize and quantify fungal colonization of habitable spaces in a biochar made from a woody feedstock. In addition to characterization of the biochar, it was necessary to optimize preparation and observation methodologies for examining fungal colonization of the biochar. Biochar surfaces and pores were investigated using several microscopy techniques. Biochar particles were compared in soilless media and after deposition in soil. Scanning electron microscopy (SEM) observations and characterization of the biochar demonstrated structural heterogeneity within and among biochar particles. Fungal colonization in and on biochar particles was observed using light, fluorescence and electron microscopy. Fluorescent brightener RR 2200 was more effective than Calcofluor White as a hyphal stain. Biochar retrieved from soil and observed using fluorescence microscopy exhibited distinct hyphal networks on external biochar surfaces. The extent of hyphal colonization of biochar incubated in soil was much less than for biochar artificially inoculated with fungi in a soilless medium. The location of fungal hyphae was more clearly visible using SEM than with fluorescence microscopy. Observations of biochar particles colonized by hyphae from soil posed a range of difficulties including obstruction by the presence of soil particles on biochar surfaces and inside pores. Extensive hyphal colonization of the surface of the biochar in the soilless medium contrasted with limited hyphal colonization of pores within the biochar. Both visualization and quantification of hyphal colonization of surfaces and pores of biochar were restricted by two-dimensional imaging associated with uneven biochar surfaces and variable biochar pore structure. There was very little colonization of biochar from hyphae in the agricultural soil used in this study.

Study on the Factors Influencing the Fluorescence Index of Internal Fluorescent Whitening Agent

This study analyzed the effects of specific factors on the fluorescence index of the fluorescent whitening agent (FWA) that is used for internal addition. The specific factors were identified by the literature review, and a statistical survey was carried out to analyze the effects of those factors on the fluorescence index. Bulk, grammage, fillers and internal sizing agents were selected as the specific factors. The paper samples were prepared with internal FWA in a laboratory. The fluorescence indices of the model papers were measured, and p-values of the specific factors on the fluorescence index were calculated by the SPSS program. Most of p-values were greater than 0.05, so the specific factors do not have a significant impact on the internal FWA fluorescence index.

Photodegradation-based detection of fluorescent whitening agents in a mountain river

Fluorescent whitening agents (FWAs) are highly soluble and poorly biodegradable ingredients used in laundry detergents and in industries (paper, textile, plastic manufacturing). They are likely to pass through biological wastewater treatment systems. The presence of FWAs in a mountain river was detected by monitoring the decay of synchronous fluorescence intensity at λex=360nm after exposing samples to ultraviolet (UV) light (365nm), for mimicking sunlight, for 15min. The method was first validated on four commercial FWAs (DAS-1, FB28, DMA-X and CBS-X) in different water matrices (deionized water and pristine river water in the presence of humic acid and dyes). A 40% decay was observed after 15min for the least photosensitive FWA (CBS-X). A field application was then performed on samples collected along a mountain river in which impacts of FWAs from domestic sources (laundry greywater) and industrial sources (paper and textile mills) were suspected. Variations of fluorescence decay at λex=360nm could be explained by these potential sources of pollution. It is suggested that the fluorescence decay at λex=280nm also be considered as an indicator, as some FWAs can exhibit fluorescence at that excitation wavelength.

Rapid detection of eight fluorescent whitening agents in textile by ultra performance convergence chromatography

An accurate quantitative and confirmative method has been developed for the deter- mination of eight fluorescent whitening agents (FWAs) in textile by ultra performance conver- gence chromatography (UPC2) coupled with photo diode array (PDA) detection, including 1,2-bis (5-methyl-2-benzoxazole) ethylene (PF), 7-diethylamino-4-methylcoumarin (SWN), 2, 2'-(2,5-thiophenediyl) bis(5-(1,1-dimethylethyl)-benzoxazol (OB), 2-[4-[2-[4-(2-benzox- azolyl) phenyl] ethenyl] phenyl] -5-methyl-benzoxazol (KSN), 1,4-bis (2-cyanostyryl) benzene (ER-I), 1-(2-cyanostyryl)-4-(4-cyanostyryl) benzene (ER-II), 2,2'-(1,4-naphthalenediyl) bis-benzoxazol (KCB), 4,4'-bis[2-(2-methoxyphenyl) ethenyl]-1,1'-biphenyl (FP). The sample was extracted with xylene and concentrated by a rotary evaporator, and then qualitatively and quantitatively analyzed by UPC2. The separation of target compounds was achieved on an ACQUITY UPC2 HSS C18 SB column (100 mm x 3.0 mm, 1.8 μm) by a gradient elution with supercritical carbon dioxide and methanol as mobile phases. External standard method was used for the quantitative determination and the calibration curves showed good linearity in the concentration range of 1.0-20.0 mg/L for the eight target compounds with correlation coefficients not less than 0.999 1. The limits of quantification of the eight compounds (LOQs, S/N = 10) were 0.70-0.95 mg/L. The average recoveries of the eight compounds ranged from 90.9% to 96.5% at the spiked levels of 2.0, 5.0, 10.0 mg/kg with the relative standard deviations (RSDs) of 2.8%-4.2%. The method is simple, accurate and time-saving with high sensitivity, and can be used for the rapid determination of the eight FWAs in textile.

Comparison of Microscopic Morphology of Fungi Using Lactophenol Cotton Blue (LPCB), Iodine Glycerol and Congo Red Formaldehyde Staining.

Comparison of Microscopic Morphology of Fungi Using Lactophenol Cotton Blue (LPCB), Iodine Glycerol and Congo Red Formaldehyde Staining.

Model-based three-way chemometric methods for quantitative analysis of linear alkylbenzene sulfonate and optical brightener in real samples using excitation–emission fluorescence data

The employed second-order calibration is one of the non-separative methods for simultaneous determination of LABS and OB in a complex matrix.

Unsustainable Land-Based Source Pollution in a Climate of Change: A Roadblock to the Conservation and Recovery of Elkhorn Coral <i>Acropora palmata</i> (Lamarck 1816)

Chronic eutrophication and turbidity are critical detrimental factors impacting coral reef ecosystems, adversely affecting their ecological functions, services, benefits, and resilience across multiple spatial scales and over prolonged periods of time. Inadequate land use practices and lack of appropriate sewage treatment can adversely contribute to increase land-based source pollution (LBSP) impacts in coastal waters and to magnify impacts by sea surface warming trends associated to climate change. Fringing coral reefs off Vega Baja, Puerto Rico, support extensive remnant patches of Elkhorn coral Acropora palmata (Lamarck 1816), which was listed in 2006 as a threatened species under the US Endangered Species Act. Chronic impacts by LBSP have significantly affected local downstream fringing reefs. We characterized the spatial extent of a water quality stress gradient across 12 reefs along the Vega Baja coast through monthly measurements of multiple physico-chemical parameters. Most parameters, particularly PO4, , chlorophyll-a, and the concentration of optical brighteners (OABs), showed a statistically significant increase (PERMANOVA, p 4, , and chlorophyll-a, exceeded recommended concentrations for coral reef ecosystems by factors of 7 - 50 times, 600 - 1240 times, and 17 - 83 times, respectively, depending on the source of the effluents and the distance from sewage pollution sources. Also, water turbidity exceeded 4 - 10 times the recommended value for pristine coral reefs. Coral reefs showed significant decline in close proximity to the polluted zone, showing a significantly different benthic community structure (PERMANOVA, p i.e., macroalgae, algal turf) and bare substrate. Percent coral cover and abundance of A. palmata, showed a significant increase with distance. Coral species richness, species diversity index, and the variance in taxonomic distinctness were very low on reef patches adjacent to the polluted zone, increased at a moderate distance with increasing coral cover and co-existence of multiple species, and declined far from the pollution source due to dominance exerted by A. palmata. This study suggests that chronic LBSP resulted in a major decline of one of the largest and most dense remnant stands of A. palmata across the northeastern Caribbean and that nutrient and chlorophyll-a concentrations were unsustainable for coral reefs. This situation requires immediate solution to prevent further damage to these unprecedented resources. It further suggests that chronic LBSP may synergistically magnify sea-surface warming impacts driving corals to an increased state of risk in face of forecasted climate change impacts. Actions to mitigate and adapt to climate change impacts on coral reefs must require a priori controls of LBSP to be effective.

Light and perspiration stability of triazinylstilbene fluorescent brighteners on cotton fabrics

Light and perspiration stability of triazinylstilbene fluorescent brighteners (TFBs) for cotton fabrics was investigated and many factors affecting the photo-fading of TFBs viz. substituent groups, artificial perspirations and their components were discussed. The experimental results indicated that the TFB with morpholine groups appeared to be the most sensitive one under simultaneous exposure to light and perspiration, whereas the TFBs containing sulfonic acid and diethanolamine groups exhibited the best stability. Among the three selected standards of artificial perspiration, the alkaline Association for Textile Technical Study standard perspiration retarded the photo-fading of TFBs on cotton fabrics remarkably. Furthermore, the study on the contribution of artificial perspiration components disclosed that the sodium salt played the predominant role in decelerating the photo-reaction of TFBs on cotton fabrics, while the influence of lactic acid was usually depended on two factors: the pH value and its reducibility.

Comparative study on the Efficacy of Agrotis segetum Granulosis virus (AgseGVEG) against Agrotis ipsilon under semi-field conditions

The present work was carried out to evaluate the efficacy of Agrotis segetum granulosis virus (AgseGVEG) against Agrotis ipsilon larvae in semi-field experiments using spray and wheat bran bait method. A Fluorescent brightener (Tinopal UNPA-GX) was added for enhancement of Agrotis segetum granulosis virus (AgseGVEG). Results showed that, addition of F. brightener 1% to AgseGVEG suspension using surface contamination technique of semi synthetic diet increased the susceptibility of 3rd and 4th instars of A. ipsilon larvae; the LC50 was 2.08×108 OB / ml and 6.10×108 OB/ml, respectively. The LT50 values of AgseGVEG (9.07×1010 OB/ml) +F. brightener 1% was7.67 and 7.85 days for 3rd and 4th instars. In addition, semi-field conditions, F. brightener 1% as sun screen enhanced AgseGVEG persistence on Cotton foliage after spray, the calculated lethal inactivation median time for 50 % reduction in virulence (lethal median inactivation time, LIT50) for 2nd instar larvae was0.97 or 2.27 days for virus alone-treatment and AgseGV+ F. brightener additive, respectively. The calculated potency value for F. brightener was 2.335 Fold. Mixture of AgseGVEG+ F. brightener 1% in bran bait formulation increased mortality% of A. ipsilon in two concentrations of AgseGVEG (9.07×109 and 9.07×108 OB/ ml) + F. brightener 1% and decreased the number of cut cotton plants infested with 3rd instar larvae of A. ipsilon compared to untreated control. The damage reduction to Cotton seedlings with A. ipsilon, was 83.33% and 70% for 3rd and 4th instars larvae, respectively, in the AgseGVEG (9.07×109 OB/ml) + F. brightener 1% compared to control. In conclusion in both spray and bran tested treatments larvae infected with AgseGVEG+ F. brightener 1% died more rapidly than those infected with AgseGVEG alone ; indicating that AgseGVEG appears to have better potential as a control agent for A. ipsilon by adding enhancement additive.

Staining ofTrichomonas vaginaliswith Fluorescent Brighteners

Objective: Infection with Trichomonas vaginalis ( T. vaginalis) is an important and common sexually transmitted infection that often is unsuspected and undiagnosed. While sensitive laboratory tests such as culture and those based on genetic probes or antigen detection are available, many laboratories still use a relatively insensitive microscopic examination of an unstained wet preparation to diagnosis this infection. Cultured T. vaginalis expresses chitin on its cell surface that fluoresces when stained with calcofluor white (CFW). This study investigated whether CFW improves the sensitivity of microscopic detection of trichomonads. Methods: Uvitex 2B and 7 different commercial preparations of CFW were tested with 23 urine and 20 vaginal specimens positive by microscopy for trichomonads. In addition to adding the fluorescence brighteners (FBs) to wet preparations, air-dried smears were stained with the FBs using a variety of fixation methods, FB concentrations, and staining duration. Ten recently isolated strains of T. vaginalis in cultures were also examined. Results: In 40 clinical specimens, no fluorescence was seen with any of the FB staining procedures used, either in wet preparations or smears; 3 vaginal specimens produced only minimal fluorescence. Some of the cultured trichomonads produced fluorescence, depending upon the age of the culture and fixation method. Conclusion: For laboratories using microscopy to detect T. vaginalis in vaginal smears and urine specimens, FBs do not appear to improve sensitivity compared with unstained wet preparations. * T. vaginalis : Trichomonas vaginalis ; FB : fluorescent brightener; CFW : calcofluor white; U2B : uvitex 2B; PBS : phosphate buffered saline; AO : acridine orange; NNDSS : National Notifiable Disease Surveillance System; RT : room temperature

Determination of trace Hg2+ ions based on the fluorescence resonance energy transfer between fluorescent brightener and CdTe quantum dots

The fluorescence resonance energy transfer between fluorescent brightener (FB, donor) and CdTe quantum dots (CdTe QDs, acceptor) was studied and a new method for detecting Hg2+ ions in water samples was accordingly developed in this paper. It was found that the effective energy transfer occurred from FB to CdTe QDs in Tris–HCl buffer solution at pH=8.2, in which the QDs' fluorescence intensity increased greatly. Then the fluorescence quenching occurred as Hg2+ interacted with CdTe. Under the optimized conditions, there was a linear relationship between the fluorescence quenching intensity and the concentration of Hg2+. Hg2+ could be determined in the concentration range of 8.0×10−9–8.0×10−7gL−1 with a detection limit of 6.6×10−10gL−1 (S/N=3). The method was applied to the determination of Hg2+ in water samples via the standard addition method, and the recovery rate obtained was 97.3–105.5%.

Low Consistency Refining of Eucalyptus Pulp: Effects on Surface Chemistry and Interaction with FWAs

The surface chemistry of eucalyptus pulp fibers prior to and after low-consistency (LC) refining was studied using a state-of-the art laboratory refining device and advanced surface analysis techniques. It was found that LC refining could generate fines and fibrillation and change the surface chemical composition of fiber surfaces. Both of these two effects can facilitate the adsorption of fluorescent whitening agents (FWAs) by the combination of increased specific surface area, electrostatic forces, and hydrophobic interactions, thus compensating for the loss of optical properties resulting from LC refining. The mechanical hydraulic force generated by the high refining energy disturbed the FWA retention. Therefore, high refining energy could improve the adsorption of FWAs when they are added after refining, but for better performance, the refining energy should be controlled and lowered. In addition, small amounts of calcium salt added after refining can also ameliorate the adsorption of FWAs.

The Design of UV Absorbing Systems for Horticultural Applications

The synthesis and fluorescence behavior of a series of bis(trisilylalkyl)anthracene molecules is described. The photodegradation of these molecules under UV light has been monitored and compared to a commercially available fluorescent optical brightener. There is a relationship between the structure and the rate of photo decay. The materials with more bulky substituents exhibit the greater stability towards UV. For bis(triphenylsilyl)anthracene the photostability appears to be comparable with a commercially available optical brightener, but the molecule may be susceptible to thermal decay.

The Determination of Fluorescent Whitening Agent VBL by Fluorescence Spectroscopy

Comprehensive method for determining the fluorescent agents was studied through studying the fluorescence spectra of different concentration of VBL. The emission and excitation wavelength in the measurement was 275nm, and 434nm, respectively. When the concentrations of VBL are changing from 0 to 1.0 μg/mL, they have a linear relationship with the emitted fluorescence intensity. In this interval, the calibration curve is y= 1 6.713x+0.7879, showing strong correlation (correlation coefficient R2 is 0.9979). The average percentage of recovery is 89.9%, which meets the measuring requirements. The interaction between VBL and CTAB is preliminary studied.

Stage‐specific insecticidal characteristics of a nucleopolyhedrovirus isolate from Chrysodeixis chalcites enhanced by optical brighteners

Chrysodeixis chalcites is a major noctuid pest of banana crops in the Canary Islands. The stage-specific susceptibility of this pest to C. chalcites single nucleopolyhedrovirus (ChchSNPV-TF1) was determined, as well as the effect of selected optical brighteners as enhancers of primary infection. Susceptibility to ChchSNPV-TF1 occlusion bodies (OBs) decreased as larval stage increased; second instars (L2) were 10,000-fold more susceptible than sixth instars (L6). Virus speed of kill was 42 h faster in L2 than in L6 . OB production increased in late instars; L6 larvae produced 23-fold more OBs than L4 . Addition of 10 mg mL(-1) Tinopal enhanced OB pathogenicity by 4.43- to 397-fold depending on instar, whereas 10 µL mL(-1) Leucophor resulted in potentiation of OB pathogenicity from 1.46- to 143-fold. Mean time to death decreased by 14 to 26 h when larvae consumed OBs in mixtures with 10 mg mL(-1) Tinopal, or 10 µL mL(-1) Leucophor, although in these treatments OB yields were reduced by up to 8.5-fold (Tinopal) or up to 3.8-fold (Leucophor). These results have clear applications for the use of ChchSNPV-TF1 as a biological insecticide in control programs against C. chalcites in the Canary Islands.

Synthesis and Characterization of Fluorescent Brightening Agents with Chiral 2(5H)-Furanone and Bis-1,2,3-triazole Structure

The multifunctional fluorescent brightening agents (FBAs) simultaneously possessing chiral 2(5H)-furanone and bis-1,2,3-triazole moieties are synthesized as designed via the Click reaction of N-[(5S)-5-menthoxy-2(5H)-furanonyl] amino acid propargyl esters with 4,4′-diazidostilbene-2,2′-disulfonate sodium salt tetrahydrate in high yields (over 90%). Their structures are systematically characterized. In addition, the testing results of their properties from fluorescence spectroscopy, photoisomerization, and ultraviolet (UV) protection factor (UPF) test show that the novel FBAs have excellent fastness to acid and light, as well as UV resistance. Especially, when a larger alkyl group in the side chain of amino acid moiety is introduced into the structure of the FBA, the designed compound has a better fluorescent brightening effect as anticipated. Moreover, in the experiments of its sorption on paper fibers, the scanning electron microscopy (SEM) images with it show a rough surface, while others without it sho...

Fluorescent Brighteners with Nitrocellulose, Nylon, and Polyvinyl Chloride Membrane Filters for In Situ Staining of Fungi in Cultures

Objective: To test the fluorescent brightening (FB) staining method, in which fungi are grown on cellulose nitrate filter membranes, dried, and rendered transparent with oil after staining with lactophenol cotton blue and to encourage use of FBs to eliminate the need for drying and clearing the membranes, therefore simplifying the procedure and reducing the time to perform it. Methods: Uvitex 2B (U2B) and 9 calcofluor white (CFW) reagents were used with 25 genera or species of fungi grown on nitrocellulose (NC), nylon (N), and polyvinyl chloride (PVC) filter membranes placed on a variety of growth media. For microscopic examination, membranes were removed from the surface of the growth medium and placed on microscope slides, with a drop of FB added to each; the preparations were then coverslipped and examined via violet light epi-illumination. Results: With many of the fungi tested, if growth was not completely inhibited, it was restricted on the PVC compared to that on the NC and N membranes and directly on a medium surface. The fluorescence of fungal structures and their contrast with the background were favorable with all 3 types of membranes and all the FBs tested. For staining yeasts on membranes from media containing polysorbate 80 (TWEEN 80), U2B is preferable to CFW because TWEEN 80 interferes with CFW staining. Conclusion: FB staining of fungi grown on NC or N membrane filters provides a rapid and simple method to examine fungal growth, especially young cultures, with minimal disturbance. * LPCB : lactophenol cotton blue; FBs : fluorescent brighteners; CFW : calcofluor white; U2B : uvitex 2B; NC : nitrocellulose; N : nylon; PVC : polyvinyl chloride; PBS : phosphate-buffered saline; cSt : centistokes

The Synthesis and Properties of Asymmetrically Substituted 4,4'-Bis(1,3,5-triazine-6-yl)diaminostilbene-2,2'-disulfonic Acid Derivatives as Fluorescent Brighteners [II

E-mail: yhmkang@hanyang.ac.krReceived February 27, 2013, Accepted April 24, 2013In this work, the key intermediate, 4-amino-4'-(2-amino-4-anilino-1,3,5-triazine-6-yl)-aminostilbene-2,2'-di-sulfonic acid, was prepared from 4-(2-amino-4-anilino-1,3,5-triazine-6-yl)amino-4'-nitrostilbene-2,2'-disulfonateby using Tin(II) chloride as the reducing agent. Using this intermediate, nineteen new asymmetrically substitutedbistriazinylstilbene fluorescent brightening agents were synthesized. Chemical structures of the obtainedcompounds 5a-s were analyzed by proton NMR spectrum. The physical properties of the new compounds5a-s were characterized by fastness test and whiteness measurement test and the obtained data were comparedto measurements obtained from CI 86.Key Words : Bistriazinylstilbene fluorescent brightening agents, 2,4,6-trichloro-1,3,5-triazine, Asymmetrical,Whiteness, FastnessIntroductionFluorescent brightening agents (FBAs) are fluorescentorganic compounds with affinity for various organic materialssuch as fiber, paper, and plastic. Typical FBAs are directdyes which can absorb ultraviolet ray (330-380 nm) andemit visible blue lights (400-450 nm).

Evaluation of land use and water quality in an agricultural watershed in the USA indicates multiple sources of bacterial impairment

Pathogens are the number one cause of impairments of assessed rivers and streams in the USA and pose a significant human health hazard. The Dry Run Creek Watershed in Northeast Iowa has been designated as impaired by the State of Iowa because of high levels of Escherichia coli bacteria. To investigate the nature of this impairment, land use and stream bank assessments were coupled with comprehensive water quality monitoring. Physical, chemical, and biological parameters were measured at 13 different sites in the watershed, including pH, temperature, conductivity, dissolved oxygen, turbidity, total Kjeldahl nitrogen, ammonia-N, nitrate + nitrite-N, total phosphorus, and E. coli. In addition, benthic macroinvertebrate communities were analyzed at seven sites, and optical brightener tests were performed late in the season. Results identified segments of the watershed that were more prominent contributors of E. coli, and correlations were observed between levels of E. coli and several chemical parameters, including ammonia-N, total Kjeldahl nitrogen, and total phosphorus. Interestingly, distinct sites emerged as more prominent contributors of these elements during rain vs. non-rain events, suggesting different types of sources. Both the amount of rainfall and the time elapsed between the rain event and the sampling influenced E. coli levels during wet weather conditions. Nitrate + nitrite-N displayed a unique response to rain events compared with the other parameters, suggesting a different delivery route. Analyses of benthic macroinvertebrate communities were consistent with pollution trends. Collectively, these data suggest distinct agriculturally related E. coli contributions, as well as specific areas and practices for water quality improvement strategies. This study can serve as a resource for evaluating agricultural watersheds that are impaired for bacteria.