Oligomeric silsesquioxanes containing dye Rhodamine B in an organic shell

A method for the synthesis of amphiphilic reactive oligomeric silsesquioxanes (OSS) with fragments of Rhodamine B fluorescent dye and hydroxyl groups in organic shell (OSS-Rh) by the reaction between carboxyl groups of the dye and epoxy groups of the mixture of oligomeric silsesquioxanes (OSS-Ep) was developed. The structure of the synthesized substance was characterized by the methods of IR and 1H NMR spectroscopy. The UV-spectrum of the OSS-Rh compound in dimethylformamide (DMF) solution was characterized by absorption bands of both the colored zwitterion (562 nm and 350 nm) and the colorless lactone (318 nm) forms of Rhodamine B. The absorption band at 562 nm in the spectrum of OSS-Rh in DMF solution was more intense than the analogous band in the spectrum of the original Rhodamine B. Therefore, the attachment of Rhodamine B to the silsesquioxane core of an oligomeric silsesquioxanes mixture does not have a significant effect on the position of the absorption maxima in UV-spectrum and prevents dye’s fragments from converting to the colorless lactone form. In the fluorescence spectra of both Rhodamine B and OSS-Rh, obtained using ethyl alcohol as a solvent, a peak is observed at λmax = 570 nm (λex = 500 nm). In the fluorescence spectrum of OSS-Rh obtained in DMF, a fluorescence peak is observed at λmax = 586 nm (λex = 520 nm). Consequently, the replacement of ethanol by DMF is accompanied by a bathochromic shift of the fluorescence peak of OSS-Rh. In the fluorescence spectrum of Rhodamine B at the same conditions, the peak of fluorescence is absent because of transition of the dye to the lactone form. The compounds obtained can be used in formation of functional Langmuir-Blodgett films as well as in obtaining polymer nanocomposites by covalent bonding.

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OLIGOMERIC SILSESQUIOXANES COMBINING AZO- AND FLUORESCENT DYES IN ORGANIC SHELL

Ukrainian Chemistry Journal ◽

10.33609/0041-6045.85.4.2019.71-80 ◽

2019 ◽

Vol 85 (4) ◽

pp. 71-80

Author(s):

Mariana Gumenna ◽

Nina Klimenko ◽

Alexandr Stryutsky ◽

Alexandr Shevchuk ◽

Viktor Kravchenko ◽

...

Keyword(s):

Absorption Band ◽

Rhodamine B ◽

Fluorescent Dyes ◽

Hydroxyl Groups ◽

Uv Spectrum ◽

Absorption Bands ◽

Organic Shell ◽

Similar Band ◽

Inorganic Nanocomposites ◽

Epoxy Groups

A method for the synthesis of reactive oligomeric silsesquioxanes, combining fragments of azo dye 4-(phenylazo)phenol and fluorescent dye Rhodamine B in various proportions in an organic shell was developed. These compounds were obtained by the reaction between the oligosilsesquioxane nanoparticles consisting of a mixture of linear, branched, ladder and polyhedral structures with epoxy groups in an organic frame (OSS–Ep) and the dyes. The structure of the synthesized substances was characterized by the methods of IR and 1H NMR spectroscopy. The UV-Vis spectra of OSS–Pp–Rh in DMF solution contain absorption bands characteristic of both acidic (560 and 350 nm) and lactone (in the range of 318–326 nm) forms of Rhodamine B. The absorption band of 4-(phenylazo) phenol fragments corresponding to π−π* transition is observed at 348 nm and overlaps the absorption band of Rhodamine B at 350 nm.The intensity of the absorption bands of fragments of various dyes depends on their content in organic frame of the silsesquioxane core. The intensity of the absorption bands at 348 nm and at 560 nm increases with an increase in the content of 4-(phenylazo)phenol and Rhodamine B correspondingly.It should be noted that when using DMF as a solvent the absorption band corresponding to acidic form of Rhodamine B at 560 nm in the UV-Vis spectra of the compounds obtained is more intense than similar band in the spectrum of the original Rhodamine B. Therefore, the attachment of Rhodamine B to the silsesquioxane core of oligomeric silsesquioxanes mixture does not have a significant effect on the position of absorption maxima in the UV-spectrum and prevents dye’s fragments from converting to the colorless lactone form. In the fluorescence spectra of OSS–Pp–Rh obtained using DMF as a solvent a peak at λ max = 592 nm (λex= 520 nm) is observed. The position of the fluorescence peak and its intensity in the spectra at the same optical density of the medium practically do not depend on the ratio of fragments of 4-(phenylazo)phenol and Rhodamine B in organic frame of OSS–Pp–Rh. The combination of two different chromophores in organic shell of the silsesquioxane core broadens the range of absorbed light and the change of their ratio allows to adjust the absorption intensity in a certain area. The presence of hydroxyl groups makes it possible to introduce the obtained compounds into the composition of polymeric organic-inorganic nanocomposites by covalent bonding.

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INVESTIGATION OF THE POSSIBILITY OF USING THE METHOD OF DIFFERENTIAL SPECTROPHOTOMETRY FOR THE ANALYSIS OF OVERLAPPING ABSORPTION BANDS OF TRITERPENE SAPONINS CHROMOPHORES AND THEIR QUANTITATIVE DETERMINATION IN AQUEOUS SOLUTIONS

chemistry of plant raw material ◽

10.14258/jcprm.2021049268 ◽

2021 ◽

pp. 267-276

Author(s):

Natal'ya Vladimirovna Mironenko ◽

Irina Viktorovna Shkutina ◽

Anastasiya Sergeyevna Kalmykova ◽

Vladimir Fedorovich Selemenev

Keyword(s):

Quantitative Determination ◽

Bathochromic Shift ◽

Aldehyde Group ◽

Carboxyl Groups ◽

Uv Spectrum ◽

Absorption Bands ◽

Quillaja Saponaria ◽

Differential Spectrophotometry ◽

Calibration Models ◽

High Concentrations

A detailed analysis of the absorption spectra of mono- and bidesmoside triterpene glycosides was performed. It is suggested that the maximum in the region of 198–208 nm is attributed to the absorption of the double bond in the cyclohexene ring of the aglycone. The second less seen maximum at a wavelength of 280 nm is observed in the spectrum of saponin Quillaja Saponaria and is almost completely absent in the spectrum of saponin Mukorossi Sapindus. Identification of this maximum is extremely difficult, since its presence can be due to both the aldehyde group in the aglycone and the hydroxyl and carboxyl groups in the carbohydrate molecules. Using the method of differential spectrophotometry, a method for decomposing the UV spectrum of saponins into its constituent components is proposed and justified. A spectral analysis was performed, including the assignment of the absorption bands to the functional groups of the studied compounds. The possibility of estimating changes in the spectral properties of glycoside solutions with changes in the acidity of the medium is considered. The possibility of a bathochromic shift of the maximum absorption of the aglyconic part of saponin depending on the microenvironment (the structure of the carbohydrate part) and changes in the pH of the solution is established. It is shown that the bands at 274, 280.5 nm correspond to n-π* transitions of carbonyl and carboxyl groups and are determined only in the regions of high concentrations in Quillaja Saponaria saponin solutions. Based on the results obtained, calibration models for the quantitative determination of saponins in solutions are proposed. The regression analysis of the calibration equations is carried out, the main statistical indicators are calculated.

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Synthesis and antimicrobial properties of oligomeric silsesquioxanes containing quaternized nitrogen atoms and hydroxyl groups in organic shell

Polymer journal ◽

10.15407/polymerj.39.03.188 ◽

2017 ◽

Vol 39 (3) ◽

pp. 188-194

Author(s):

M.A. Gumenna ◽

◽

N.S. Klimenko ◽

A.V. Stryutsky ◽

D.M. Hodyna ◽

...

Keyword(s):

Antimicrobial Properties ◽

Hydroxyl Groups ◽

Organic Shell

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Self-Assembled Nanomaterials Based on Complementary Sn(IV) and Zn(II)-Porphyrins, and Their Photocatalytic Degradation for Rhodamine B Dye

Molecules ◽

10.3390/molecules26123598 ◽

2021 ◽

Vol 26 (12) ◽

pp. 3598

Author(s):

Nirmal K. Shee ◽

Hee-Joon Kim

Keyword(s):

Aqueous Solution ◽

Visible Light Irradiation ◽

Rhodamine B ◽

Self Assembly ◽

The Self ◽

Assembly Process ◽

Absorption Bands ◽

Ligand Coordination ◽

Rhodamine B Dye ◽

Metal Ligand

A series of porphyrin triads (1–6), based on the reaction of trans-dihydroxo-[5,15-bis(3-pyridyl)-10,20-bis(phenyl)porphyrinato]tin(IV) (SnP) with six different phenoxy Zn(II)-porphyrins (ZnLn), was synthesized. The cooperative metal–ligand coordination of 3-pyridyl nitrogens in the SnP with the phenoxy Zn(II)-porphyrins, followed by the self-assembly process, leads to the formation of nanostructures. The red-shifts and remarkable broadening of the absorption bands in the UV–vis spectra for the triads in CHCl3 indicate that nanoaggregates may be produced in the self-assembly process of these triads. The emission intensities of the triads were also significantly reduced due to the aggregation. Microscopic analyses of the nanostructures of the triads reveal differences due to the different substituents on the axial Zn(II)-porphyrin moieties. All these nanomaterials exhibited efficient photocatalytic performances in the degradation of rhodamine B (RhB) dye under visible light irradiation, and the degradation efficiencies of RhB in aqueous solution were observed to be 72~95% within 4 h. In addition, the efficiency of the catalyst was not impaired, showing excellent recyclability even after being applied for the degradation of RhB in up to five cycles.

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Synthesis and biotical activity of bacterial cellulose 6-(2-phthalimidoethanesulfonate)

Butlerov Communications ◽

10.37952/roi-jbc-01/20-61-2-29 ◽

2020 ◽

Vol 61 (2) ◽

pp. 29-36

Author(s):

Zoya P. Belousova ◽

Keyword(s):

Bacterial Cellulose ◽

Side Reaction ◽

Hydroxyl Group ◽

Hydroxyl Groups ◽

Cellulose Derivatives ◽

Wound Surface ◽

Reaction Products ◽

Absorption Bands ◽

Hydroxymethyl Group ◽

Antibacterial And Antifungal

Bacterial cellulose obtained by culturing Gluconacetobacter sucrofermentans in HS environment was converted to sulfonate derivatives using methane-, toluene- and 2-phthalimidoethanesulfonic acids in pyridine. When the ratio of the starting reagents is 1 : 1, the modification of bacterial cellulose according to the primary hydroxyl group of glucopyranose fragments is most likely. The formation of 6-substituted bacterial cellulose derivatives was observed in the reaction mixture. The IR spectra of the reaction products contain absorption bands, which are specific for (O–SO2) group in the region 1377-1338 cm−1 (as), 1178-1154 cm−1 (s), fragments of the corresponding sulfonic acids, as well as free hydroxyl groups of glucopyranose in the region 3495-3382 cm−1. Bacterial cellulose 2-phthalimidoethanesulfonate was dissolved in pyridine. After drying with a desiccant in a desiccator, it turned into a dense transparent film of brown color. The increased molecular film allows to explain the side reaction occurring between the oxo group and fragments of one of the chains of modified cellulose and the non-substituted hydroxymethyl group. The IR spectrum of bacterial cellulose 6-(2-phthalimidoethanesulfonate) contains absorption bands in the region 1711 cm−1, which are specific for (Ar–CO–O) group, and absorption bands in the region 1618 cm−1, which prove the presence of (CO–NH) group. In order to impart antibiotic properties to the bacterial cellulose 6-(2-phthalimido-ethanesulfonate) film, it was physically modified with clotrimazole. The obtained experimental data showed that the films subjected to treatment with a 1% solution of clotrimazole have antibacterial and antifungal effects and prevent the growth of pathogenic microbiota on the wound surface. The exit rates of clotrimazole from the bacterial cellulose 6-(2-phthalimidoethanesulfonate) film and from the pure bacterial cellulose film differed, but only slightly. 2-Phthalimidoethanesulfonate bacterial cellulose films can be used to form composites of effective wound covering, since in addition to the unique properties of bacterial cellulose itself (low allergenicity and adhesion to the wound surface, high hygroscopicity) they will have a regenerating effect.

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SYNTHESIS AND SPECTRAL CHARACTERISTICS OF PERSPECTIVE NANOSIZED CARBON QUANTUM DOTS FOR ADSORPTION AND CATALYTIC PROCESSES

Ukrainian Chemistry Journal ◽

10.33609/0041-6045.86.1.2020.3-11 ◽

2020 ◽

Vol 86 (1) ◽

pp. 3-11

Author(s):

Volodymyr Ogenko ◽

Svitlana Orysyk ◽

Ljudmila Kharkova ◽

Oleg Yanko

Keyword(s):

Quantum Dots ◽

Bathochromic Shift ◽

Spectral Characteristics ◽

Carbon Quantum Dots ◽

Hypsochromic Shift ◽

Absorption Bands ◽

Rhodium Chloride ◽

Electron Transitions ◽

Trivalent State ◽

Adsorption Processes

Processes of interaction between carbon quantum dots (CQDs) and solutions of rhodium, ruthenium and palladium chlorides in the surface layer have been investigated by electron and IR spectroscopy. When rhodium chloride is added to a solution of CQDS, a bathochromic shift of the β- and p-absorption bands (ABs) at 48725 and 41711 cm-1 as well as hypsochromic shift of the α-AB at 28935 cm-1 indicate that rhodium adsorption occurs on the surface of CQDs. The bathochromic shift of the absorption bands at 22400 сm1 together with the hypsochromic shift of ABs corresponding to d-d electron transitions in the metal ions indicates the formation of rhodium with CQDs. When ruthenium and palladium chlorides are added to an aqueous solution of CQDs, the intensive of ABs characterizing the complex anions [RuCl6]3-, [RuCl6]2- or [PdCl4]2- are absent in the UV-Vis spectra. This indicates the passage of adsorption processes of metals on the surface of CQDs. The present of ABs (at 27055 and 25125 сm-1) indicate the trivalent state of ruthenium ion; the p-ABs bathochromic shift as well as α-ABs hypsochromic shift indicates the probable complex formation of CQDs with Ru3+ ions. The change in the position of the absorption bands of d-d electron transitions (at 25448 сm1) together with the bathochromic shift of p-ABs and hypsochromic shift of α-ABs indicates a change in coordination environment in the palladium ion with the possible formation of Pd → N bond. The IR-spectra data of CQDs showed the presence of a number of characteristic ABs for functionalized CQDs: ν(N–H) at 3260 сm1, (C=O) at 1830, 1840 and 1850 сm1, –С=O(NH) at 1770 сm1, ν(C=N) at 1680 and δ(N–H) at 1640 сm1, which confirms the coordination of metals on the surface of CQDs.

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Cell adhesion to hydroxyl groups of a monolayer film

Journal of Cell Science ◽

10.1242/jcs.91.2.269 ◽

1988 ◽

Vol 91 (2) ◽

pp. 269-279

Author(s):

N.F. Owens ◽

D. Gingell ◽

A. Trommler

Keyword(s):

Cell Adhesion ◽

Flow Chamber ◽

Cell Contact ◽

Hydroxyl Groups ◽

Adjacent Area ◽

Oh Groups ◽

Monomolecular Films ◽

Langmuir Blodgett Films ◽

Long Chain Alcohol ◽

Minimal Measure

We have studied cells on chemically defined monomolecular films of the long-chain alcohol docosanol. Langmuir-Blodgett films of the alcohol were deposited on glass coverslips, previously made hydrophobic with octadecyl groups. This gives films in which the alcohol headgroups face outwards to the water. Molecular orientation and film integrity were shown by a fluorescence adsorption test. Cell contacts on the films were observed in media without proteins by interference reflection microscopy (IRM) and the mechanics of detachment were examined by hydrodynamic shearing in a flow chamber. Cell contact with docosanol was compared with that on an adjacent area of octadecyl glass without a monolayer. Dictyostelium amoebae settled and spread on both docosanol and octadecyl glass, but little or no locomotion was seen on docosanol. On octadecyl glass the amoebae moved actively, forming ultrathin cytoplasmic lamellae, which look dark under IRM, and left distinctive trails of membranous debris. Hydrodynamic shearing showed that the amoebae stuck strongly to both surfaces and could not be removed from either at the maximum attainable wall shear stress of 6Nm-2. Red blood cells also adhered to both surfaces and removal from both occurred between 1 and 3Nm-2. IRM and scanning electron microscopy (SEM) studies indicated that this force leads to a minimal measure of red cell adhesion, since removal often involved the breakage of cytoplasmic tethers. Our results show that alcoholic -OH groups, in a two-dimensional array, provide a surface that is strongly adhesive for cells. No other method has made it possible to demonstrate cell adhesion purely to -OH groups, in a known orientation and density, and in the absence of any other functional groups on the interface.

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Simultaneous measurement of the fluorescence spectrum and lifetime of Rhodamine B in solution with a fluorometer based on streak-camera technologies

Analytical Chemistry ◽

10.1021/ac00099a005 ◽

1995 ◽

Vol 67 (3) ◽

pp. 511-518 ◽

Cited By ~ 9

Author(s):

Mitsuru. Ishikawa ◽

Motoyuki. Watanabe ◽

Tsuyoshi. Hayakawa ◽

Musubu. Koishi

Keyword(s):

Fluorescence Spectrum ◽

Rhodamine B ◽

Simultaneous Measurement ◽

Streak Camera

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Six-fold C–H borylation of hexa-peri-hexabenzocoronene

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.16.37 ◽

2020 ◽

Vol 16 ◽

pp. 391-397 ◽

Cited By ~ 1

Author(s):

Mai Nagase ◽

Kenta Kato ◽

Akiko Yagi ◽

Yasutomo Segawa ◽

Kenichiro Itami

Keyword(s):

Density Functional ◽

Bathochromic Shift ◽

Density Functional Theory Calculations ◽

Absorption Bands ◽

Functional Theory ◽

X Ray ◽

X Ray Crystallography ◽

Polycyclic Aromatic ◽

Direct Functionalization ◽

Poorly Soluble

Hexa-peri-hexabenzocoronene (HBC) is known to be a poorly soluble polycyclic aromatic hydrocarbon for which direct functionalization methods have been very limited. Herein, the synthesis of hexaborylated HBC from unsubstituted HBC is described. Iridium-catalyzed six-fold C–H borylation of HBC was successfully achieved by screening solvents. The crystal structure of hexaborylated HBC was confirmed via X-ray crystallography. Optoelectronic properties of the thus-obtained hexaborylated HBC were analyzed with the support of density functional theory calculations. The spectra revealed a bathochromic shift of absorption bands compared with unsubstituted HBC under the effect of the σ-donation of boryl groups.

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