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The purpose of this paper is to modify the photostability of organic fluorescent dyes and to develop and evaluate a route of their derived polymeric fluorescent dyes.

A series of novel polymeric fluorescent dyes were prepared using 3-(2-benzimidazolyl)-7-(diethylamino)-coumarin (disperse yellow 8GFF, abbreviated as 8GFF) and polyethylene glycol (PEG) as raw materials. First, an intermediate of carboxyl functioned 8GFF was prepared by condensation reaction of 8GFF and pyromellitic dianhydride; and then the polymeric fluorescent dyes were synthesized by reacting PEG with the condensate intermediate.

FTIR, UV-vis, and PL showed that the polymeric fluorescent dyes had been successfully synthesised, and the photostability of organic fluorescent dyes was improved significantly.

In the present work, the polymeric fluorescent dyes had been successfully synthesized, and the photostability of organic fluorescent dyes was improved significantly. This methodology can be employed to prepare novel polymeric fluorescent materials and to improve the photostability of organic dyes for various applications.

Polycondensable dyes offer a new area of material science which can be widely used in coloured polymer materials production.

The method developed in the study reported in this paper provided a new strategy to develop new types of polycondensable dyes materials with fluorescent property.

This paper aims to focus on the most popular technique nowadays, the use of microwave irradiation in organic synthesis; in a few years, most chemists will use microwave energy to heat chemical reactions on a laboratory scale. Also, many scientists use microwave technology in the industry. They have turned to microwave synthesis as a frontline methodology for their projects. Microwave and microwave-assisted organic synthesis (MAOS) has emerged as a new “lead” in organic synthesis.

Using microwave radiation for synthesis and design of fluorescent dyes is of great interest, as it decreases the time required for synthesis and the synthesized dyes can be applied to industrial scale.

The technique offers many advantages, as it is simple, clean, fast, efficient and economical for the synthesis of a large number of organic compounds. These advantages encourage many chemists to switch from the traditional heating method to microwave-assisted chemistry.

This review highlights applications of microwave chemistry in organic synthesis for fluorescent dyes. Fluorescents are a fairly new and very heavily used class of organics. These materials have many applications, as a penetrant liquid for crack detection, synthetic resins, plastics, printing inks, non-destructive testing and sports ball dyeing.

The aim value of this review is to define the scope and limitation of microwave synthesis procedures for the synthesis of novel fluorescent dyes via a simple and economic way.

The aim of this paper was to prepare a stable fluorescent disperse yellow paste by wet grinding process by adding naphthalene sulphonic derivative dispersing agent.

The dispersants 2-naphthalenesulphonic acid (NNO), naphthalene-sulphonic acid (MF) and benzyl naphthalene sulphonate formaldehyde condensate (CNF) were used to disperse the yellow dye. The particle size of the paste was characterised by particle size analyser. The paste centrifugal stability, diffusion properties, morphology and thermal properties were also tested for assessing its stability which could be helpful to prepare inks with good stability.

The particle sizes of dye pastes with dispersing agent NNO, MF and CNF were 161.1, 150.0 and 136.0 nm, respectively, after grinding for 6 h. The dye paste grinded with dispersing agent CNF presented good centrifugal and thermal properties. TEM images demonstrated that the morphologies of dye pastes grinded with dispersing agent MF and CNF were homogeneous nearly spherical nanoparticle and rarely generated agglomeration and precipitation.

The paste used for aqueous inkjet ink exhibited excellent thermal stability.

The purpose of this study is evaluate the optical properties of polyacrylonitrile (PAN) nanofibers containing fluorescent agents such as fluorescent dye and carbon quantum dots (CQDs) by using image-processing technique of Fluorescence microscope image.

The fluorescence microscope image of the pure PAN, PAN/CQDs and PAN/fluorescent dye nanofibers composite was analyzed using several image-processing techniques such as color histogram, lookup table (LUT), Fourier transform, RGB profile and surface plot analysis.

The fluorescence microscope image indicates that the fluorescence emission of nanocomposites depends on the type of fluorescent agent. The fluorescence intensity of nanofiber containing CQDs is more than nanofiber containing fluorescent dye. Various image-processing methods provide similar results for optical property of nanocomposites. Analyzing the LUT, the blue value of CQDs/PAN nanocomposite image was significantly higher than other nanocomposites. This was confirmed by other methods such as Fourier transform, color histogram and 3D topography of the electrospun nanofibers. According to analysis of colorimetric parameters, higher negative value of b* indicates bluer color for CQDs/PAN nanofibers than other nanocomposites. The obtained results indicate that the image-processing technique can be used to evaluate the optical property of fluorescent nanocomposite.

This study evaluates the optical properties of fluorescent nanocomposites by using image-processing techniques such as Fourier transform, color histogram, RGB profiles, LUT, surface plot and histogram analysis.

The purpose of this paper is to explore the optic performance of extended stilbene derivative.

Five steps were adopted to synthesise novel 4, 4′-bis (2-cyanostyryl) stilbene, which contained three vinyl units in the skeleton (S3E). The structure of S3E was characterised by ¹H NMR and EI-MS. Its absorption and emission spectra were also given.

Compared to C.I. Fluorescent Brightener 199, which contains two vinyl units in the skeleton, S3E showed obvious bathochromic shifts in both UV-VIS and FL spectra. The maximum absorption wavelength and fluorescent wavelength were at 390 nm and 464 nm, respectively, with Stoke’s shift of 74 nm. The absolute fluorescence quantum yield was 0.42. Thermogravimetric analysis (TGA) revealed that the weight loss of S3E was less than 5 per cent at 300 °C. Moreover, the light resistance test showed that S3E in PVC plate can keep the good fluorescent intensity for more than seven days exposed to xenon light. Therefore, it is believed that S3E could satisfy the requirements of colouring PVC as a fluorescent dye.

S3E can be used as a candidate of fluorescent dye in the development of thermoplastics.

The present paper designed and synthesised a new derivative of stilbene, which showed its preference to be a colourant of thermoplastics.

A disperse fluorescent yellow paste was mixed with a dispersant naphthalene sulfonic derivative via wet grinding process to prepare thermal transfer ink with good fluorescence. The paper aims to discuss these issues.

The surface tension, viscosity, pH value, zeta potential, stability and the morphology of ink samples were tested after the storing process.

The morphology of paste was homogeneous nearly spherical nanoparticles and the particle size was about 100 nm from the transmission electron microscopy (TEM), which was similar to the average particle size obtained from the particle size analyser.

The paste particle size was 126.8 nm after storing at 50°C for one week. The addition of diethylene glycol was conducive to high fluorescent reflectivity and gave good line image quality both in warp and weft directions due to the low viscosity. Inkjet printed polyester fabrics achieved excellent rubbing, laundering and thermal subliming fastnesses.

The polyester fabrics thermal transferred with the ink contained diethylene glycol represented higher fluorescent reflectivity and gave better line image quality both in warp and weft directions. The inkjet printed polyester fabrics showed excellent colour reproducibility and all the fastnesses, including rubbing, laundering and thermal subliming, were higher than Grade 4.

The purpose of this study is to develop a non-enzymatic based glucose-sensing platform composed of Bodipy-BBV dual system which can be monitored by a photodetector under the blue LED excitation.

The sensor has been developed from a dual system including a fluorescent dye, an aldehyde derivative of boron dipyrromethene (Bodipy) and a quencher, orto-boronic acid linked viologen (o-BBV) where their combination resulted in a ratiometric fluorescence quenching in ethanol: PBS (1:1, pH:7.4) solution under UV light excitation. By glucose addition, o-BBV has been released from the Bodipy and binded to cis-diol groups of glucose, thereby fluorescence emission of Bodipy has been regained. Furthermore, a setup consisting of a light emitting diode (LED) and a photodiode (PD) was used to prove electrical detection of glucose without the need for expensive and bulky optical equipment, enabling the development of a miniaturized and low-cost glucose-sensing platform.

The fluorescence intensity of the Bodipy derivative in the solution (2 × 10⁻⁶ M) was diminished by 93% in the presence of o-BBV solution (5 × 10⁻³ M). Upon the glucose addition, 81% of the Bodipy fluorescence intensity has been recovered after introduction of 30 mM of glucose, where the ratio of o-BBV/Bodipy was 35:1. A linear response between 10 and 30 mM glucose concentration was obtained, which covers the biologically significant range. A high correlation between the photodiode current and Bodipy fluorescence intensity was achieved.

Even though Bodipy molecules are known with their superior optical properties and applied to the fluorescence-based detection of glucose, to the best of the authors’ knowledge, no work has been reported on Bodipy-BBV dual system to detect glucose molecules as a non-enzymatic based method. This design enables the dye and the quencher to independently coexist in the solution, allowing for tuning of their individual concentrations to optimize the glucose sensitivity. Furthermore, an electrical light detection scheme consisting of a LED and a photodiode has been implemented to eliminate the bulky optical equipment from the measurement setup and further this work for the development of a compact and inexpensive sensor. The results presented here demonstrate the feasibility of this system for the development of a novel glucose sensor.

The other day I visited an exhibition of paintings in an art gallery. It was not too well lit, and one painting stood out immediately because of a small but extremely brightly coloured area on it. As I went closer I saw that the bright area was painted with a daylight fluorescent colour which was applied over a white background. The artist stood nearby, but I did not have the heart to tell him that, if he ever became famous, his fame would outlast the bright fluorescent area in his painting.

The purpose of this paper is to visualize protein manipulation using dielectrophoresis (DEP) as a substantial perspective on being an effective protein analysis and biosensor method as DEP is able to be used as a means for manipulation, fractionation, pre-concentration and separation. This research aims to quantify DEP using an electrochemical technique known as cyclic voltammetry (CV), as albumin is non-visible without any fluorescent probe or dye.

The principles of DEP were generated by an electric field on tapered DEP microelectrodes. The principle of CV was analysed using different concentrations of albumin on a screen-printed carbon electrode. Using preliminary data from both DEP and CV methods as a future prospect for the integration of both techniques to do electrical quantification of DEP forces.

The size of the albumin is known to be 0.027 µm. Engineered polystyrene particle of size 0.05 µm was selected to mimic the DEP actuation of albumin. Positive DEP of the sample engineered polystyrene particle was able to be visualized clearly at 10 MHz supplied with 20 Vpp. However, negative DEP was not able to be visualized because of the limitation of the apparatus. However, albumin was not able to be visualized under the fluorescent microscope because of its translucent properties. Thus, a method of electrical quantification known as the CV technique is used. The detection of bovine serum albumin (BSA) using the CV method is successful. As the concentration of BSA increases, the peak current obtained from the voltammogram decreases. The peak current can be an indicator of DEP response as it correlates to the adsorption of the protein onto the electrodes. The importance of the results from both CV and DEP shows that the integration of both techniques is possible.

The integration of both methods could give rise to a new technique with precision to be implemented into the dialyzers used in renal haemodialysis treatment for manipulation and sensing of protein albumin.

FLAW detection processes utilizing dye penetrants are now extensively used throughout the aircraft industry. They are a logical development of the lard oil and chalk method popular in the early days, a system which is still occasionally used for economic reasons and where only the more obvious flaws are of significance. Briefly, this method consists of immersing the parts to be tested in hot lard oil, wiping off the excess, and then applying a film of chalk; oil which has seeped into surface flaws eventually exudes out and is absorbed into the chalk, revealing itself as typical oily stains. It was reasoned that if lard oil were substituted by a penetrating medium which was highly coloured, the exudations would then become much more obvious and from then on intensive research programmes were started which have culminated in the very efficient processes now available.