Synthesis of dyes and pigments

Pereinamieji metalai (tokie, kaip gyvsidabris, švinas) yra itin toksiški ir net nedidelis jų kiekis organizme gali sukelti daugybinius organų pažeidimus, sutrikdyti medžiagų apykaitą, imuninę sistemą. Taip pat šie elementai yra kancerogenai, į organizmą daugiausiai patenkantys dėl oro/vandens/dirvožemio taršos, su maistu. Pereinamieji metalai kaupiasi organizme.
Šių elementų detekcijos tyrimai turi didelę reikšmę tiek Lietuvoje, tiek pasaulyje. Plačiausiai paplitę yra spektrofotometriniai ir elektroanalitiniai metalų jonų aptikimo metodai, tokie kaip atominės absorbcijos/emisijos spektroskopija, induktyviai susietos plazmos masės spektroskopija (ICP-MS).
Veikiant Brooker‘s Merocyanine solvatochrominį dažiklį pereinamųjų metalų tirpalais, jo spalva gali pakilti arba pagilėti. Pagal dažiklio ir metalo jono komplekso spalvos intensyvumą galima nustatyti, kokia pereinamojo metalo jonų koncentracija yra tiriamajame mėginyje.

Ląstelių dažai, skirti dažyti pagrindinius ląstelių komponentus, yra svarbūs reagentai daugelyje biologinių tyrimų aspektų.

Atliekant ląstelių mikroskopiją, jie leidžia tyrėjui paprasčiau nustatyti pagrindines struktūras ir sritis su ląstelėmis ar audiniais. Pagrindinės cheminės savybės taip pat lemia tam tikro dažiklio naudojimą, pavyzdžiui jo gebėjimas pereiti pro membraną ar prisirišti prie tam tikros ląstelės struktūros.

„Darrow Red“ yra paprastasis oksazino dažiklis , kuris gali būti naudojamas neuronų ląstelių kūnams dažyti. Šio dažiklio analogai yra taikomi vėžinių ląstelių tyrimams, tačiau pačio „Darrow Red“ dažiklio pritaikomumas šioms ląstelėms dar nėra ištirtas. „Darrow Red“ dažiklis šiuo metu nėra komerciškai parduodamas, taip pat nėra aprašyta jo sintezė. Dažiklis buvo sintetinamas pagal analogiškos struktūros junginių aprašus, o gautų nudažytų ląstelių tyrimų rezultatai lyginami su kitų jau žinomų dažiklių rezultatais.

Šio darbo tikslas – susintetinti „Darrow Red“ dažiklį ir naudojant HPLC-MS metodą nustatyti jo grynumą bei pritaikomumą gyvūninėms ląstelėms dažyti.

Darbo uždaviniai:
1.Išanalizuoti panašios struktūros dažiklių sintezę ir jų pritaikymą ląstelių dažymui teoriniu aspektu
2.Susintetinti „Darrow Red“ dažiklį ir išgryninti iki pakankamo grynumo ląstelių dažymui (>95%).
3.Susintetintą „Darrow Red“ pritaikyti dažant gyvūnines ląsteles, nustatyti jo sąveiką su ląstele ir geriausią dažiklio koncentraciją.

Darbe tirti Thermus aquaticus YT-1 bakterijų lizato skaidrinimo, naudojant tangentinio mikrofiltravimo sistemą, dėsningumai. Tarpusavyje lygintos komercinės 0,2 µm ir 0,65 µm skersmens porų membranos. Abiems membranoms parinktos optimalios proceso atlikimo sąlygos. Kiekvienai membranai nustatytas optimalus membranos savitasis našumas, įvertintos baltymų, nukleorūgščių, polisacharidų ir tikslinio produkto Taq DNR polimerazės išeigos, jų sulaikymo koeficientai bei praėjimo per membraną greičio konstantos. Nustatyta, kad membranos savitasis našumas yra didesnis naudojant 0,2 µm skersmens porų membraną, o produkto išeiga siekia 96,3 ±3,7 %. Taip pat parodyta, kad medžiaga, iš kurios pagaminta membrana, turi įtakos proceso našumui. Apibendrinus visus rezultatus nustatyta, kad T. aquaticus YT-1 bakterijų lizatui skaidrinti, gaunant didžiausią Taq DNR polimerazės išeigą, reikia naudoti 0,2 µm skersmens porų membraną.

The aim of the article is to acquaint restorers
and researchers of Buddhist painting on canvas
with traditional restoration methods combined with
modern equipment and materials that are used in the
Laboratory of Scientific Restoration of Oriental Painting
of the State Hermitage Museum. The relevance
of this work is dictated by the development restoration
practice of Buddhist painting in recent decades.
It is shown in the study how the emergence of new
high-tech materials, equipment and methods of
studying monuments allows the restorer to work with
them more effectively. Also in this paper, the results
of the study and study of two thangkas are shown.
Comprehensive the thangka study conducted by the
specialists of research laboratories made it possible
to choose the right restoration techniques. In addition,
a brief work of historical information about the
iconography and technology of creating a thangka is
provided. The restoration techniques and their choices
are analyzed in the article. Also the ethical problems
related to the permissible degree of interference in the
structure of the monument are examined. Using the
example of comparing approaches to the restoration
of two Buddhist thangkas restored in different years:
the “Dorje Lakpa Buddhist Image” thangka in 2018,
and the “Mahakala blue, 6-handed, 3-eyed, standing
on an elephant with a human figure” thangka in 2021,
various techniques are described. The analysis of the
restoration measures carried out includes a description
of the studies carried out on the monuments before
the restoration, and methods of cleaning the surface,
strengthening the paint layer, replenishing the soil,
leveling the base and replenishing the losses of the
paint layer. The article shows the practical significance
and effectiveness of the use of various materials,
equipment and methods of restoration of Buddhist
painting. In conclusion, the results of the restoration
of both monuments are summarized

To examine the steric effects of the in-plane ligands in dye-sensitized {RuNO} 6 nitrosyls on their NO photolability, two new ligands, namely, 1,2-Bis(pyridine-2-carboxamido)-4,5-dimethoxybenzene (H 2 (OMe) 2 bpb) and 1,2-Bis(Isoquinoline-1-carboxamido)-4,5-dimethoxybenzene (H 2 (OMe) 2 IQ1, H's are dissociable carboxamide protons) have been designed and synthesized. The syntheses and spectroscopic properties of {RuNO} 6 nitrosyls derived from these two ligands, namely, [((OMe) 2 bpb)Ru(NO)(Cl)] (4-Cl), [((OMe) 2 IQ1)Ru(NO)(Cl)] (5-Cl), [((OMe) 2 bpb)Ru(NO)(Resf)] (4-Resf), and [((OMe) 2 IQ1)Ru(NO)(Resf)] (5-Resf), are reported. The structures of 5-Cl, 4-Resf, and 5-Resf have been determined by X-ray crystallography. Removal of the in-plane ligand twist in the quinoline-based R 2 bQb 2ligand frame (because of steric interactions between the extended quinoline ring systems) in both R 2 bpb 2and R 2 IQ1 2-(pyridine and 1-isoquinoline rings, respectively, instead of quinoline rings in the equatorial plane) results in enhanced solution stability, as well as higher quantum yield values for NO photorelease upon exposure to 500 nm light. Both dyetethered {RuNO} 6 nitrosyls 4-Resf and 5-Resf exhibit greater sensitivity to visible light compared to the chloro-bound species 4-Cl and 5-Cl. In addition, the dye-tethered nitrosyls are fluorescent and hence can be used as trackable NO donors in cellular studies.

Patikslinta glikomakropeptido nustatymo liesame piene efektyviosios skysčių chromatografijos būdu metodika. Tirta pieno baltymų nusodinimo temperatūros ir sušaldymo temperatūros įtaka mėginyje nustatomai glikomakropeptido koncentracijai. Vietoj dviejų nuosekliai sujungų gelchromatografinių kolonėlių TSK-2000 SW naudojant vieną didesnės skiriamosios gebos kolonėlę TSK gel G 2000 SWXL, glikomakropeptidą atitinkančios chromatogramos smailės eliuavimo trukmė sumažėjo maždaug 7 min. Nustatyta, kad tiriant glikomakropeptido koncentraciją atšaldytuose (+8 °C) ar sušaldytuose (-18 °C) pieno mėginiuose, baltymus nusodinti galima ne tik 25 °C temperatūroje, kaip nurodyta metodikoje, bet ir pilant trichloracto rūgštį į atšaldytą ar sušaldytą mėginį ir po to jį pašildant iki 25 °C. Toks mėginių paruošimo režimas neturi statistiškai reikšmingos įtakos nustatomai glikomakropeptido koncentracijai piene. Raktažodžiai: glikomakropeptidas, efektyvioji skysčių chromatografija, baltymų nusodinimo temperatūra.

2007-2013 m. Žmogiškųjų išteklių plėtros veiksmų programos 2 prioriteto "Mokymasis visą gyvenimą" VP1-2.2-ŠMM-03-V priemonę "Mokymo personalo, dirbančio su lietuvių vaikais, gyvenančiais užsienyje, užsienio šalių piliečių vaikais, gyvenančiais Lietuvoje, ir kitų mokymosi poreikių turinčiais mokiniais, kompetencijų tobulinimas" projektas "Gamtos mokslų mokytojų eksperimentinės veiklos kompetencijos tobulinimas atnaujintų mokymo priemonių ir 9-12 klasių bendrųjų programų pagrindu (VP1-2.2-ŠMM-03-V-01-002)". Projekto vykdytojas-Lietuvos edukologijos universitetas. Partneriai-Vytauto Didžiojo universitetas ir Šiaulių universitetas.

Recent plans to clean and restore Vincent van Gogh's painting of his Bedroom in Arles (Van Gogh Museum, Amsterdam)sparked off a broad collaborative campaign of investigations to compare the materials and techniques used in all three painted versions of this theme, ...

Recent plans to clean and restore Vincent van Gogh's painting of his Bedroom in Arles (Van Gogh Museum, Amsterdam)sparked off a broad collaborative campaign of investigations to compare the materials and techniques used in all three painted versions of this theme, ...

Straipsnyje nagrinėjamas javų kombaino nuožulniojo transporterio guoliai vibro analizės metodu, kai kombainas dirba maksimaliais sūkiais. Tyrimų obektu pasirinkatas Jonh Deere firmos klavišiniai kombainai. Tiriamas nuožulniojo transporterio guolis AH231479.Matavimams pasi-rinktas Bruel&Kjaer įranga, kuris turi akselerometra 4370,duomenų kaupiklį 3580 ir kompiuterį su programine įranga (pulse). Iš atliktų bandymų ir apskaičiuotų dažnių galima teigti, kad pagal kombaine esančių guolių virpesius galime nustatyti guolių techninę būklę neišardant mazgoThe article examines the bearer conveyor bearings of the combine harvester by the vibration analysis method, when the combine works at maximum speed. Of the conventional Jonh Deere brand combines were chosen as the research object. Bruel & Kjaer equipment with accelerometer 4370, data carrier 3580 and computer with software (pulse) are selected for measurement. From tests performed and calculated frequencies, we can say that we can determin...

Problems of technology LOCOS, related with oxidation time, temperature, silicon oxide layer, patterned silicon nitride in CMOS structure was researched. During LOCOS most CMOS quality depend on gate channel shortening, diffusion region separation. LOCOS CMOS mathematical models are created using program SUPREM. It is determined, that most acceptable results are received when time t=360 min., temperature T=1000oC, SiO2 thickness = 0,02 μm., Si3N4 thickness = 0,1 μm. Ill. 10, bibl. 5 (in Lithuanian, summaries in Lithuanian, English and Russian).

Šis sukurtas metodas geba atpažinti kofeiną apie 205 ir 273 nm bangos ilgio naudojant HPLC. Šis metodas skirtas tolimesnei analizei, tiriant kofeino kiekį kavoje be kofeino. Šis validacijos protokolas yra skirtas patvirtinti HPLC metodą skitą kofeino kiekiui mėginiuose nustatyti.

Recent studies have shown that modern pigments produced after the Second Industrial Revolution are complex systems characterized by a high level of heterogeneities. Therefore, it is fundamental to adopt a multianalytical approach and highly sensitive methods to characterize the impurities present within pigments. In this work we propose time-resolved and spectrally resolved photoluminescence (PL) microscopy for the mapping of luminescent crystal defects and impurities in historical cadmium-based pigments. PL analysis is complemented by X-ray diffraction, X-ray fluorescence and Raman spectroscopies, and by scanning electron microscopy to determine the chemical composition and crystal structure of samples. The study highlights the heterogeneous and complex nature of historical samples that can be associated with the imperfect manufacturing processes tested during the period between the 1850s and 1950s. The results also allow us to speculate on a range of synthesis processes. Since it ...

Star-shaped charge transporting materials with a triphenylamine core and a varying number of diphenylethenyl sidearms, obtained using a one step synthesis procedure from commercially available and relatively inexpensive starting materials and possessing comparatively high hole drift mobility (up to 0.017 cm 2 V À1 s À1), are reported. Scheme 1 Synthesis of diphenylethenyl substituted triphenylamines 1-3.

Recent studies have shown that modern pigments produced after the Second Industrial Revolution are complex systems characterized by a high level of heterogeneities. Therefore, it is fundamental to adopt a multianalytical approach and highly sensitive methods to characterize the impurities present within pigments. In this work we propose time-resolved and spectrally resolved photoluminescence (PL) microscopy for the mapping of luminescent crystal defects and impurities in historical cadmium-based pigments. PL analysis is complemented by X-ray diffraction, X-ray fluorescence and Raman spectroscopies, and by scanning electron microscopy to determine the chemical composition and crystal structure of samples. The study highlights the heterogeneous and complex nature of historical samples that can be associated with the imperfect manufacturing processes tested during the period between the 1850s and 1950s. The results also allow us to speculate on a range of synthesis processes. Since it ...

Various diazotized aryl amines were coupled with N-(4-nitrophenyl)-2-[(4-phenyl-1,3-thiazol-2-yl)amino]acetamide to give the corresponding various azo disperse dyes (D1-D13). These dyes were applied to polyester fiber by HTHP method and their fastness properties were evaluated. Dyes were characterized by IR, elemental analysis, and NMR spectral studies. These dyes showed very good antibacterial and antifungal activities.

Diazotized aryl amines were coupled with two stenhouse salt namely, N-(5-phenylaminopenta-4-ol-2,4-diene-1-ylidene)anilines hydrochloride [S 1 (R‚H) or S 2 (R‚OH)] to furnish two series of disazo disperse dyes (S 1 D 1-10 and S 2 D 1-10). The structure of all the dyes was established by estimating number of azo groups, elemental analysis and spectral studies (IR, 1 H-NMR, UV/ Visible). The structure-property relationship was discussed by using electronic absorption spectra of the dyes. These dyes were applied to polyester and nylon fabrics as disperse dyes by using temperature exhaust dyeing method. The relevant dyeing characteristics, such as dyeability on fabrics, wash-fastness and light-fastness were evaluated. Fabrics dyed with these dyes furnished generally deep and bright intense hues ranging from light yellow to orange to reddish brown. The color fastness of the dyed fabric was assessed by determining wash-fastness and light-fastness properties.

SUTRUMPINIMAI ATM-atominės jėgos mikroskopija, Atomic Force microscopy. AES-atominė emisinė spektrofotometrinė analizė, Atomic Emission spectrometry. CIE-L*a*b*-spektrofotometrinės kolorimetrijos metodas, rekomenduotas CIE, Commission Internationale de l'Eclairage. DCMA-sausų dažų gamintojų asosiacija, Dry Colours Manufacturers Association. EDS-energijos dispersinė spektrometrija. Energy-dispersive spectrometry. EDTA-etilen-diamin-tetra acto rūgštis. EDX-energijos dispersinė rentgeno spindulių analizė, Energy Dispersive Xray analysis. EDXRF-energijos dispersinė spindulių fluorescencinė analizė, Energy Dispersive X-ray Fluorescense analysis. EXAFS-Rentgeno spindulių absorbcijos spektroskopija, Extended X-ray absorption fine structure spectroscopy. FTIR-Furje transformacinė infraraudonoji spektroskopija, Furier transformative Infrared spectroscopy. IR-infraraudonoji spektroskopija, Infrared spectroscopy. Mikro-Sy-RFA-mikro-sinchrotroninė rentgeno spindulių fluorescencinė analizė, Mikro-Synchrotron induced X-ray Fluorescense analysis. MRS-mikro-Raman spektroskopija, Micro-Raman spectroscopy. PLM-poliarizuotos šviesos mikroskopija, Polarized light microscopy. PIXE-protonų indukcinė Rentgeno spindulių emisinė analizė, Proton induced X-ray Emission analysis. PIGE-protonų indukcinė gama spindulių emisinė analizė, Proton induced Gamma ray Emission analysis. RBS-protonų ir helio indukcinė Rutherfordo emisinė analizė, Proton and helium-Rutherford backscattering. REM-rastrinė elektroninė mikroskopija, Raster electron microscopy.

Nine variously substituted azo dye derivatives2–10of antipyrine were prepared. The effects of the nature and orientation of the substituents on the color and dyeing properties of these dyes for polyester fibers were evaluated. The newly synthesized compounds were characterized on the basis of elemental analyses and spectral data. On the other hand, the investigated dyes were applied to polyester fabrics and showed good light, washing, heat, and acid perspiration fastness. The remarkable degree of brightness after washings is indicative of the good penetration and the excellent affinity of these dyes for the fabric. The results in general revealed the efficiency of the prepared compounds as new monoazo disperse dyes. The newly synthesized compounds were screened for their antioxidant and cytotoxic activity against Vitamin C and 5-fluorouracil, respectively. The data showed clearly that most of the compounds exhibited good antioxidant and cytotoxic activities.

New tricyanofuran intramolecular charge transfer dyes comprising the hydrazone group were prepared and fully characterized in order to study their possible solvatochromism, dyeing ability, and antimicrobial activity. The preparation of the hydrazone dyes was achieved in relatively good yields starting from different aromatic amines. The hydrazone functional group was presented via the azo-coupling reaction of the tricyanofuran compound by the properly substituted diazonium chloride. Chemical structures of the prepared hydrazones were confirmed via nuclear magnetic resonance spectroscopy (1H- and 13C-NMR), Fourier-transform infrared spectroscopy (FT-IR), and elemental analysis (C, H, and N). The UV-visible absorption spectra of the produced sensor colorants displayed interesting solvatochromism in solvents with a different polarity, which was found to be affected by the substituents bonded to the aromatic hydrazone moiety. The pH molecular switching was investigated through tuning th...

The present work describes the synthesis of a series of four novel biologically active 2-amino-5-arylazothiazole disperse dyes containing the sulfa drug nucleus. The structures of the synthesized thiazole derivatives are confirmed using UV-spectrophotometry, infrared and nuclear magnetic resonance techniques and elemental analysis. The synthesized dyes are applied to polyester fabrics as disperse dyes and their fastness properties to washing, perspiration, rubbing, sublimation, and light are evaluated. The synthesized compounds exhibit promising biological efficiency against selected Gram-positive and Gram-negative pathogenic bacteria as well as fungi.

Triphenylamine (TPA), a propeller shaped optoelectronic molecule, has been used to generate stimuli-responsive smart fluorescent organic materials and correlate the effect of subtle structural change on the molecular packing and mechanochromic fluorescence (MCF). The substituent (OCH 3) position in the TPA phenyl ring and acceptors (malononitrile, cyanoacetamide, cyanoacetic acid, ethyl cyanoacetate and diethylmalonate) influenced strongly on the solid state and mechanochromic fluorescence as well as molecular packing. The structure-property studies revealed that (i) TPA derivatives without OCH 3 substituent exhibit strong fluorescence (Φ f = 85 % (TCAAD-1, 55 % (TDEM)), (ii) higher dihedral angle (τ) between donor (aminophenyl) and acceptor lead to weak/non fluorescent material, (iii) substituent at ortho position to acceptor increased the dihedral angle (τ = 26.49 (TCAAD-2), τ = 27.14 (TDMM)) and (iv) the increase of alkyl groups produced self-reversible high contrast off-on fluorescence switching materials (TDEM). PXRD studies indicate that stimuli induced reversible phase transformation from crystalline to amorphous and vice-versa was responsible for fluorescence switching. The computational studies also supported that OCH 3 substitution at ortho to acceptor increased the dihedral angle and optical band gap. Thus, the present studies provide a structural insight for designing TPA based organic molecules for developing new smart organic materials.

Maya blue is a marvelous pigment with extraordinary properties. It was invented by the Maya around VII-VIII century and used by many Mesoamerican peoples in prehispanic times. It is made by encapsulating natural indigo into an inorganic clay matrix of palygorskite. The palygorskite-indigo mixture becomes acid-resistant when a moderate thermal treatment is applied. The chemical reasons of the unusual stability of the pigment and the exact mechanism of interaction between the indigo and the clay are not well understood. We present a Raman study of different preparations of Maya blue and other mixtures of indigo with other inorganic materials. We found that the unheated mixture of indigo with palygorskite presents the same Raman spectrum as Maya blue, indicating that the differences with respect to the indigo spectrum are not due to the interaction produced during the thermal treatment, which makes the mixture acid-resistant. Moreover, indigo mixed with other clays, like sepiolite or montmorillonite, presents a Raman spectrum very similar to that of Maya blue. Some chemical mechanisms that could explain these spectra, and the suitability of Raman spectroscopy for identifying Maya blue are discussed.

This work reports the results of a study of the influence of the structure of some open-chain diamines on their retention in highperformance ion chromatography (HPIC). We examine a set of eight diamines, in which the N atoms are separated by two C atoms and are differently N-and C-alkyl substituted; four of these diamines have the same formula weight. In the other two sets, the diamines are different from each other, either in terms of the length of the alkyl chain between the N atoms or in terms of the length of the substituent(s) on the nitrogen atom(s). The mobile phase is a mixture of HClO 4 0.100 mol/L, 0.160 < C NaClO 4 < 1.50 mol/L, and 0 < acetonitrile% ≤ 15 (v/v). The amines are detected by integrated amperometry. Interpretation of experimental data shows that (a) elution occurs for both ionic and hydrophobic interactions and is dependent on all the components of the mobile phase, (b) the diamines are eluted in any case as dications, and (c) steric hindrance significantly influences elution times. Some examples of separation are proposed.

A series of some new substituted 5-antipyrinylazo-4-phenyl-2-aminothiazole disperse dyes was synthesized by diazocoupling of 4-antipyrinyldiazonium chloride with aminothiazole derivatives. The synthesized dyes were characterized by UV-Vis absorption, IR, 1 H NMR, and MS spectroscopy. The dyes gave orange to reddish-violet shades with very good depth and levelness when applied to polyester fabrics as disperse dyes and their fastness properties were evaluated on polyester fibers. Also the position of color in CIELAB coordinates (L à , a à , b à , H à , and C Ã) was assessed.

New tricyanofuran intramolecular charge transfer dyes comprising the hydrazone group were prepared and fully characterized in order to study their possible solvatochromism, dyeing ability, and antimicrobial activity. The preparation of the hydrazone dyes was achieved in relatively good yields starting from different aromatic amines. The hydrazone functional group was presented via the azo-coupling reaction of the tricyanofuran compound by the properly substituted diazonium chloride. Chemical structures of the prepared hydrazones were confirmed via nuclear magnetic resonance spectroscopy (1H- and 13C-NMR), Fourier-transform infrared spectroscopy (FT-IR), and elemental analysis (C, H, and N). The UV-visible absorption spectra of the produced sensor colorants displayed interesting solvatochromism in solvents with a different polarity, which was found to be affected by the substituents bonded to the aromatic hydrazone moiety. The pH molecular switching was investigated through tuning th...

The aim of this study was to synthesize disperse dyes in the derivative of 2-amino-4-chloro-5-formylthiazole by conventional diazotization and couplings with pyridone and resorcinol. The dyes were characterized by visible absorption spectroscopy, IR spectral studies, and 1H and 13C NMR. The pyridone and resorcinol substituted dyes exhausted well with good depth on 100% polyester fabrics with a shade of brown and purple colours, respectively. The heteroatom and the intrinsic conjugation in the thiazole structure results in high bathochromic shifts and lead to brightness of shades. The dyed fabrics showed very good to excellent wash fastness and moderate to good light and perspiration fastness properties.

An active methylene compound, malononitrile, was introduced into the structures of a series of disperse dyes previously prepared by coupling phloroglucinol, barbituric acid, and α and β-naphtho to 4-amino-3-nitrobenzaldehyde. The dyes were purified by recrystallization from ethanol. The purity of the dyes was examined by thin-layer chromatography (TLC) and the dyes were characterized by visible absorption and Fourier transform infrared spectroscopy (FTIR). The malononitrile-condensed dyes produced deeper colours and shades with better fastness to wash, light, and perspiration on application to polyester and nylon fabrics when compared to their uncondensed analogue.

„Nile Red“ yra fluorescencinis, lipofilinis organinis dažiklis naudojamas fluorescencinėje  mikroskopijoje mikroplastikų selektyviam atpažinimui ir biologiniuose tyrimuose norint lokalizuoti ląstelės
lipidus ir kiekybiškai juos nustatyti. Mikroskopijai tinkamo „Nile Red“ komercinė kaina yra apie 150 eurų už 100 mg. Klasikinis „Nile Red” sintezės metodas paremtas DMF (N,N-dimetilformamidas) panaudojimu.

DMF tirpiklio panaudojimo apribojimas [3] buvo patvirtintas 2021 m. lapkričio 19 d. ir turi būti taikomas visoje ES nuo 2023 m. gruodžio 12 d., todėl yra aktualu optimizuoti metodą, paremtą kitu tirpikliu, kuris galėtų pakeisti  DMF „Nile Red“ sintezėje, išlaikant optimalią junginio savikainą.

Tyrimo tikslas. Atlikti fluorscenciniai mikroskopijai tinkamo grynumo „Nile Red“ sintezę ir grynimą, nenaudojant N,N-dimetilformamido.

Metodai. Sintezės metodas: nitrozinimo reakcijos metu iš 3-dietilaminofenolio gaunamas 5-dietilamino-2-nitrosofenolis – tarpinis reakcijos produktas. Tarpinis produktas su 1-naftoliu ištirpdomi
organiniame tirpiklyje. Atliekant „Nile Red“ sintezę naudojami penki skirtingi organiniai tirpikliai: acetonas, N,N-dimetilformamidas, dimetilsulfoksidas, metanolis, toluenas.

Analizės metodas: po reakcijos mėginys analizuojamas naudojant HPLC-MS metodą. Gautoje chromatogramoje analazijuoma „Nile Red“ procentinė dalis reakcijos mišinyje.

Gryninimo metodas: naudojama sausos kolonėlės vakuuminė chromatografija su pasirinkta heksano-izopropanolio sistema reakcijos mišiniui gryninti. Surinktos frakcijos tikrinamos TLC metodu siekiant patikrinti komponentų atsiskyrimą. Švariausios frakcijos sujungiamos, rotaciniu garintuvu pašalinamas tirpiklis. Nustatyti grynumui naudojamas HPLC-MS metodas.

Rezultatai. „Nile Red“ išeiga, naudojant skirtingus reakcijos tirpiklius: N,N-dimetilformamidas (26%);  dimetilsulfoksidas (21%); metanolis (21%); toluenas (9%). Acetone „Nile Red“ sintezė neįvyko. Atlikus „Nile Red“
gryninimą pasiektas 92% grynumas.

Naudojant išgrynintą „Nile Red“ paruoštas 1 mM dimetilsulfoksido
tirpalas. Tirplas buvo testuotas fluorescenciniu mikroskopijos metodu, kas patvirtino junginio tinkamumą.

Išvada. Optimizuotas sintezės metodas leidžia atsisakyti N,N-dimetilformamido, kuris, atsižvelgiant į tyrimo rezultatus, gali būti pakeists į dimetilsulfoksidą ar metanolį beveik be išeigos praradimo, o gauto produkto grynumas tinkamas taikymui gyvybės moksluose. Tikslinga optimizuoti reakcijos laiką siekiant  padidinti „Nile Red“ sintezės išeigą.

An active methylene compound, malononitrile, was introduced into the structures of a series of disperse dyes previously prepared by coupling phloroglucinol, barbituric acid, and α and β-naphtho to 4-amino-3-nitrobenzaldehyde. The dyes were purified by recrystallization from ethanol. The purity of the dyes was examined by thin-layer chromatography (TLC) and the dyes were characterized by visible absorption and Fourier transform infrared spectroscopy (FTIR). The malononitrile-condensed dyes produced deeper colours and shades with better fastness to wash, light, and perspiration on application to polyester and nylon fabrics when compared to their uncondensed analogue.

• The rheological properties of 19th century white paint formulations have been compared. • Lead and zinc white paints both exhibit viscoelastic properties, characteristic of paste suspensions. • Yield stress and elastic moduli are strongly dependant on the nature, treatment and proportion of oil. • At all studied concentrations, yield stress and elastic modulus at 1 Hz are higher for zinc white paints.

The present study concerns the technology of Tibetan wall painting i.e. the pigments, binding medium and stratigraphic build-up. Original Tibetan materials were brought to the School of Conservation in Denmark by two Tibetan artists. Pigments and binding medium were analysed by Attenuated Total Reflection Fourier-transformed Infrared Spectroscopy (ATR-FTIR), Micro-Raman Spectroscopy (MRS), X-ray powder Diffraction (XRD), Scanning Electron Microscopy Energy Dispersive X-ray spectroscopy (SEM-EDX), High Performance Liquid Chromatography with Diode-Array Detector (HPLC-DAD) and thermally assisted Hydrolysis and Methylation Gas Chromatography-Mass Spectrometry (THM-GC-MS). The proteinaceous binding medium which was expected to be Yak ox (Bos grunniens) glue was identified by DNA analysis. The painting techniques of the Tibetan artist were followed during their painting of a traditional wall painting. The results show that several pigments were adulterated compared to the artists’ belief...

New tricyanofuran intramolecular charge transfer dyes comprising the hydrazone group were prepared and fully characterized in order to study their possible solvatochromism, dyeing ability, and antimicrobial activity. The preparation of the hydrazone dyes was achieved in relatively good yields starting from different aromatic amines. The hydrazone functional group was presented via the azo-coupling reaction of the tricyanofuran compound by the properly substituted diazonium chloride. Chemical structures of the prepared hydrazones were confirmed via nuclear magnetic resonance spectroscopy (1H- and 13C-NMR), Fourier-transform infrared spectroscopy (FT-IR), and elemental analysis (C, H, and N). The UV-visible absorption spectra of the produced sensor colorants displayed interesting solvatochromism in solvents with a different polarity, which was found to be affected by the substituents bonded to the aromatic hydrazone moiety. The pH molecular switching was investigated through tuning th...

Purpose – The purpose of this paper is to synthesise some new 5-arylazothiazole disperse dyes and study their application in dyeing polyester fibres. Design/methodology/approach – A series of 5-arylazo-2-(arylidenehydrazino)-4-substituted-thiazole dyes were prepared ...

3-Hydrazine-4,5,6-triphenylpyridazine was used as key intermediate for synthesis of 3-(4-arylazo-3,5-disubstituted pyrazol-1-yl)-4,5,6-triphenylpyridazines. Some of the dyes produced were applied to polyester as disperse dyes, and their color, and fastness properties were evaluated.

ABSTRACT The synthesis of novel cycloalkane ring-fused arylazopyrazolo[1,5-a]pyrimidines, using 4-arylazo-3-aminopyrazol-5-ones as starting components, is described in this paper. The dyeing application and the dyeing characteristics of the dyes synthesised are also reported.

Combination of mercaptothiazoles and mercury phenyl chloride synthesized some new compounds of thiazoles. Firstly some mercaptothiazoles with different sorts have been synthesized, and then synthesized compounds were reacted with different mercury phenyl chloride structures. At last, each of these synthesized compounds was purified. Consequently, these structures were recrystallized using oil ether. Forming product through chromatogram (TLC) and combination ofRfwith other compound&#39;sRfof were identified, and their purity percent was recognized. The1H-NMR and other methods like FT-IR and mass spectroscopy have determined all of compounds. Obtained results of synthesized compounds showed that reactions were carried out with suitable speed and high yield.

This work presents an algorithm to reduce the multiplicative computational complexity in the creation of digital holograms, where an object is considered as a set of point sources using mathematical symmetry properties of both the core in the Fresnel integral and the image. The image is modeled using group theory. This algorithm has multiplicative complexity equal to zero and an additive complexity (k-1)N2 for the case of sparse matrices or binary images, where k is the number of pixels other than zero and N2 is the total of points in the image.

Raman and infrared spectroscopy are two complementary spectroscopic techniques that can produce fast, efficient and accurate detection of the pigments and/or binders used in automotive topcoats. Micro-Raman spectroscopy, due to its non-destructiveness, has been extensively used for identification of pigments and dyes in forensic investigation of hit-and-run accidents. This technique provides very useful and significant information from very small samples of evidence without any previous preparation of the sample. The recorded Raman spectra of the unknown/ suspected samples can be compared with a spectrum of the referent sample, which can coincide with the one already existing in the Raman database of pigments. In order to form our own spectral database of automotive paints for forensic investigations in hit-and-run offences in Republic of Macedonia, an investigation of automotive topcoats of different origins was carried out. In our previous study, pigments in some automotive topcoa...

Various diazotized aryl amines were coupled with N-(4-nitrophenyl)-2-[(4-phenyl-1,3-thiazol-2-yl)amino]acetamide to give the corresponding various azo disperse dyes (D1-D13). These dyes were applied to polyester fiber by HTHP method and their fastness properties were evaluated. Dyes were characterized by IR, elemental analysis, and NMR spectral studies. These dyes showed very good antibacterial and antifungal activities.

Four imines, the condensation products of 2,4-dioxo-4-phenylbutanal with four primary amines, were condensed with mercapto acetic acid to obtain thiazolidinon-4-ones which on subsequent condensation with vanillin and isatin separately yielded eight thiazolidin-4-one derivatives. The chemical structures of the synthesized compounds were elucidated by elemental analysis, molecular weight determination, IR and1H and13C NMR spectral measurements. Antibacterial and antifungal properties were studiedin vitroagainst two bacteria and two fungi. The dyeing potential of synthesized reactive dyes was investigated with regard to silk, wool, cotton, and polyester fabrics under hot and cold dyeing conditions.

A detailed spectroscopic analysis of two dichloro substituted phenyl-N-(1,3-thiazol-2-yl)acetamides at 2,4 and 3,4 positions of the phenyl ring has been carried out by using B3LYP method with 6-31+G(d, p) basis set within density functional scheme. The scaled theoretical wave numbers are in perfect agreement with the experimental values and the vibrational modes are interpreted in terms of potential energy distribution (PED). The internal coordinates are optimized repeatedly to maximize the PED contributions. The molecular HOMO-LUMO surfaces, their respective energy gaps, and MESP surfaces have also been drawn to explain the chemical activity of both molecules. Various thermodynamic parameters are presented at the same level of theory.

Synthesis of new acid dyes, mono azo and diazo derived from 3-[2-(cyanomethyl)-thiazol-4-yl]coumarin and 3-(2-amino-thiazol-4-yl)coumarin using various derivatives amine, and their utilization in dyeing of textile fabrics is attempted in this article. The prepared dyestuffs were established using melting point, elemental analysis, infrared, ultraviolet-visible spectroscopy (UV/VIS) and nuclear magnetic resonance (1 H-NMR) data. The suitability of the prepared dyestuffs for dyeing of wool and silk fabrics has been investigated. The dyed fabric show good light fastness, very good rubbing, perspiration, washing and excellent sublimation fastness. These dyes have been color shade from blue to violet with very good depth and levelness on fabrics. The dye bath exhaustion and fixation on fabric has been found to be very good.

Various diazotized aryl amines were coupled with N-(4-nitrophenyl)-2-[(4-phenyl-1,3-thiazol-2-yl)amino]acetamide to give the corresponding various azo disperse dyes (D1-D13). These dyes were applied to polyester fiber by HTHP method and their fastness properties were evaluated. Dyes were characterized by IR, elemental analysis, and NMR spectral studies. These dyes showed very good antibacterial and antifungal activities.

Diazotized aryl amines were coupled with 3-substituted 5-amino pyrazoles to produce a series of novel 3-substituted 5-amino-4-arylazopyrazoles. Also, 3-substituted 5-amino-pyrazoles were diazotized and coupled with different phenols to give the corresponding novel 3-substituted 5-aryl azo pyrazoles. These dyes were characterized by elemental analysis and spectral data, applied to different types of fibres (wool, polyester and a blend of wool/polyester as

Maya blue is a marvelous pigment with extraordinary properties. It was invented by the Maya around VII-VIII century and used by many Mesoamerican peoples in prehispanic times. It is made by encapsulating natural indigo into an inorganic clay matrix of palygorskite. The palygorskite-indigo mixture becomes acid-resistant when a moderate thermal treatment is applied. The chemical reasons of the unusual stability of the pigment and the exact mechanism of interaction between the indigo and the clay are not well understood. We present a Raman study of different preparations of Maya blue and other mixtures of indigo with other inorganic materials. We found that the unheated mixture of indigo with palygorskite presents the same Raman spectrum as Maya blue, indicating that the differences with respect to the indigo spectrum are not due to the interaction produced during the thermal treatment, which makes the mixture acid-resistant. Moreover, indigo mixed with other clays, like sepiolite or montmorillonite, presents a Raman spectrum very similar to that of Maya blue. Some chemical mechanisms that could explain these spectra, and the suitability of Raman spectroscopy for identifying Maya blue are discussed.

Maya blue is a marvelous pigment with extraordinary properties. It was invented by the Maya around VII-VIII century and used by many Mesoamerican peoples in prehispanic times. It is made by encapsulating natural indigo into an inorganic clay matrix of palygorskite. The palygorskite-indigo mixture becomes acid-resistant when a moderate thermal treatment is applied. The chemical reasons of the unusual stability of the pigment and the exact mechanism of interaction between the indigo and the clay are not well understood. We present a Raman study of different preparations of Maya blue and other mixtures of indigo with other inorganic materials. We found that the unheated mixture of indigo with palygorskite presents the same Raman spectrum as Maya blue, indicating that the differences with respect to the indigo spectrum are not due to the interaction produced during the thermal treatment, which makes the mixture acid-resistant. Moreover, indigo mixed with other clays, like sepiolite or montmorillonite, presents a Raman spectrum very similar to that of Maya blue. Some chemical mechanisms that could explain these spectra, and the suitability of Raman spectroscopy for identifying Maya blue are discussed.