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1

Cyclodextrin-assisted dispersive liquid-liquid microextraction based on solidification of floating organic droplets coupled with HPLC for the determination of pyrethroid residues in cereals

Jiang Haijuan, Bi Xinyuan, Huang Xin, Guo Xingle, Zou Ziyu, Li Ying, Jing Xu, Wu Junxue

Acta Chromatographica

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2023

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Vol. 35, no. 1

21--27

EN

A simple, rapid, and environmentally friendly sample preparation method for pyrethroids determination in cereals using cyclodextrin-assisted dispersive liquid-liquid microextraction based on solidification of floating organic droplets coupled with high-performance liquid chromatography was established. The cereal samples were extracted with acetonitrile, cleaned up, and concentrated by green extractant menthol via γ-cyclodextrin assisted extraction process. The extractant menthol dispersed as fine droplets in the cyclodextrin solution and then solidified at room temperature for efficient extraction and convenient collection. The optimized method provided good linearity in the range of 0.01–10 mg kg⁻¹ with limits of detection of 3.5–9.5 μg kg⁻¹. The fortified recoveries of three pyrethroids (i.e., lambda-cyhalothrin, deltamethrin, and bifenthrin) in four cereals (i.e., rice, wheat, maize, and millet) at three levels were in the range of 77.6–101.6% with relative standard deviations of 0.6–6.6%. Overall, the proposed method can be successfully applied for the determination of pyrethroids in cereals.

2

Grafting Modification of Natural Fibres with Cyclodextrin

Liu Jinshu, Ma Xiaoyan, Shi Wenzhao, Xing Jianwei, Ma Chaoqun

Fibres & Textiles in Eastern Europe

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2020

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Vol. 28, no. 6 (144)

15--23

EN

Over the years, a multiplicity of grafting modification techniques have been studied to combine the adsorption and wettability of natural fibres with the capacity of cyclodextrins (CDs) to form inclusion complexes. The fixation of CDs on fibres is possible using crosslinking agents or reactive derivatives of cyclodextrins. Various crosslinking chemicals are suitable to bind the hydroxyl groups of non-reactive cyclodextrins with those of natural fibres by way of spraying, padding, surface coating, and impregnation. Nano-composite dense polimer film could also be formed to anchor the cyclodextrin on the natural fibre surface by the methods of hydrogen binding or covalent binding in sol-gel. A vinyl monomer such as glycidyl methacrylate was used to form polymer coatings due to the pendant epoxy group coupled with the –OH of cyclodextrin and natural fibres. This review also focused on the derivatives of CDs with the reactive group reacting with the hydroxyl groups of natural fibres.

PL

Przez lata badano wiele technik szczepienia, aby połączyć adsorpcję i zwilżalność włókien naturalnych ze zdolnością cyklodekstryn (CD) do tworzenia kompleksów inkluzyjnych. Utrwalanie CD na włóknach jest możliwe przy użyciu środków sieciujących lub reaktywnych pochodnych cyklodekstryn. Różne chemikalia sieciujące są odpowiednie do wiązania grup hydroksylowych niereaktywnych cyklodekstryn z tymi z włókien naturalnych poprzez natryskiwanie, napawanie, powlekanie powierzchni i impregnację. W celu zakotwiczenia cyklodekstryny na powierzchni włókien naturalnych metodami wiązania wodoru lub wiązania kowalencyjnego w zolu-żelu można zastosować możliwość tworzenia nano-kompozytowej folii polimerowej. W pracy do utworzenia powłok polimerowych użyto monomeru winylu – metakrylan glicydylu. W artykule skupiono się również na pochodnych CD z grupą reaktywną reagującą z grupami hydroksylowymi włókien naturalnych.

3

Cyclodextrine vs D-glucose in the solutions of the derivative of 1,4-DHP

Kaczmarek-Klinowska Milena, Hornowski Tomasz

Vibrations in Physical Systems

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2019

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Vol. 30, nr 1

art. no. 2019110

EN

Hydrophilic and hydrophobic cyclodextrins (CDs) have found a lot of applications in medicine pharmacology, food processing and cosmetology. They can function as a drug carrier material and parent host molecules, increasing drug biocompatibility, optimizing the efficiency of drug activity, and controlling drug release at the desired level. The effectiveness of CD complexation depends on many factors such as the type and the size of both the CD molecule itself and the guest molecule, pH of the solution, and temperature. In aqueous solution of glucose the aggregation of molecules can occur leading to the formation of CD-like structures. In the paper the possibility of the formation of the inclusion complexes of CD and glucose with Nimodipine was investigated with the aid of ultrasonic spectroscopy. By comparing the efficiency of industrial saccharides and glucose in the formation of the inclusion complexes the cost effectiveness of the use of glucose as a substitute for CD can be determined.

4

Properties of the Gamma-Cyclodextrin/CL-20 System

Maksimowski P., Rumianowski T.

Central European Journal of Energetic Materials

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2016

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Vol. 13, no. 1

217--229

EN

Cyclodextrin (CD) is a cyclic compound with a spatial structure in the shape of a toroid. It is characterized by specific properties. The outer portion of the structure has hydrophilic properties, while the cavity of the toroid is hydrophobic. This enables cyclodextrin to form inclusion complexes with the enclosure of lipophilic molecules in the interior. This paper presents the results of attempts to form a complex of γ-CD/CL-20. This study determined unambiguously that a γ-CD with CL-20 complex in a mole ratio 1:1 is formed as a result of mixing of solutions of γ-CD and CL-20. This conclusion was corroborated by FTIR, 1H NMR, UV-Vis spectroscopic techniques and by measurement of the density of the complex obtained. The resulting complex of γ-CD/CL-20 is characterized by much lower sensitivity to friction and impact than CL-20 itself.

5

Eco-Friendly Simultaneous Chromatographic Determination of Amiloride Hydrochloride, Atenolol, and Hydrochlorothiazide in Urine

Albishri H. M., El-Hady D., Tayeb R. A.

Acta Chromatographica

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2015

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Vol. 27, no. 3

461--476

EN

Pharmaceutical industry concerned recently with eco-friendly analytical methods to reduce the environmental pollution. The using of toxic organic solvents for the analysis of drugs is critical. In the current work, several simple and less costly approaches such as micellar and/or cyclodextrin liquid chromatography were discussed. A new eco-friendly and simple chromatographic analysis of the ternary mixture of amiloride hydrochloride (AM), atenolol (AT), and hydrochlorothiazide (HZ) in urine by hydroxypropyl-beta-cyclodextrin (HP-β-CD) bonded stationary phase was investigated. The experimental conditions were optimized and validated based on International Conference on Harmonization (ICH) Q2R1 guidelines to detect analytes by isocratic mobile phase of phosphate buffer (5.0 mmol L-1, pH 7.0) in the presence of 0.5 mL min-1 flow rate, 25.0 °C, and 280 nm. Linearity, accuracy, and precision were found to be acceptable over the concentration range of 0.05–20.0 μg Ml-1 for AM, 0.05–50.0 μg Ml-1 for AT and 0.05–50.0 μg Ml-1 for HZ. The proposed method was precise, selective, and sensitive enough for the routine analysis of ternary mixture at therapeutic urine levels. The inclusion complexation and the appendant hydroxyl groups of HP-β-CD were considered the main reasons for assisting in adequate separation of the drugs. On the other hand, the presence of kosmotropic phosphate ions could solubilize the protein and could strengthen the selective inclusion of drugs inside HP-β-CD cavity. Urinary excretion studies showed that the detection of drugs is possible up to 24 h after their ingestion.

6

Inclusion complexation of 2-aminopyrimidines with β-cyclodextrin, physico-chemical and nuclear magnetic spectroscopic studies

Celin T S, Nagarajan S

Materials Science Poland

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2014

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Vol. 32, No. 1

39--44

EN

Inclusion complexation of 2-aminopyrimidines with b-cyclodextrin was studied in the solid state by infrared spectroscopy (IR), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). The aminopyrimidine-b-CD complexes were also investigated in a solution by nuclear magnetic resonance spectral techniques (1H-NMR and 13C-NMR). Qualitative modifications in the position and number of peaks or bands obtained from spectral methods as well as thermal analysis indicated the inclusion.

7

Electrospinning of Poly(acrylonitrile-acrylic acid)/β Cyclodextrin Nanofibers and Study of their Molecular Filtration Characteristics

Amiri P, Bahrami S H

Fibres & Textiles in Eastern Europe

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2014

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Vol. 22, no. 1 (103)

14--21

EN

Acrylonitrile acrylic acid copolymer was synthesised using suspension polymerisation and β-cyclodextrin was mixed with this copolymer in different ratios. then poly(acrylonitrileacrylic acid)/-cyclodextrin (PANAA/-CD) nanowebs were produced using the electrospinning process. The effect of different electrospinning parameters such as polymer concentration, distance, flow rate and voltage on nanofibre properties was studied. The presence of CD molecules in the PANAA solutions did not affect the diameter of nanofibres significantly. The presence of CD molecules in the PANAA/CD nanofibres produced was studied by means of Fourier transform infrared (FTIR) spectroscopy. The molecular filtration capability of the nanowebs produced was studied using phenolphthalein as a model organic molecule, by means of a UV-Vis Spectrophotometer. Results show that the nanofibres produced are able to remove phenolphthalein effectively from the solution. These nanowebs have the potential to be used as a molecular filter and/or nanofilter for filtration/purification/separation purposes.

PL

Syntezę kopolimeru akrylonitrylu i kwasu akrylowego przeprowadzono w zawiesinie, β-cyklodextran był mieszany z kopolimerem w zróżnicowanych ilościach. Następnie runo (PANAA/-CD) było wytwarzane metodą elektroprzędzenia. Badano wpływ różnych parametrów procesu, takich jak stężenie polimeru, odległość od filiery, szybkość przepływu i napięcie, na właściwości nanowłókien. Obecność molekuł CD w roztworach PANAA nie wpływała istotnie na średnicę nanowłókien. Badania przeprowadzono stosując metodę spektroskopii FTIR. Zdolność runa do filtracji molekularnej badano przy zastosowaniu fenoloftaleiny oraz spektrofotometrii UV-Vis. Badania wykazały, że wyprodukowane nanowłókna są zdolne do eliminacji fenoloftaleiny z roztworu. Wyprodukowane runa potencjalnie mogą być wydajnie zastosowane jako filtry molekularne oraz dla filtracji, oczyszczania i separacji.

8

Wpływ środowiska achiralnego na rozróżnienie chiralne pochodnych pirolidyno-2-onu w kolumnie cyklodekstrynowej

Górska M., Bielejewska A., Kulig K., Leś A., Widomski P., Żukowski J.

Przemysł Chemiczny

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2012

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T. 91, nr 9

1834-1841

PL

Zbadano retencję i rozdzielenie na enancjomery serii 15 racemicznych pochodnych pirolidyn-2-onu w kolumnie tri(3,5-dimetylolfenylokarboilo)-β-cyklodekstrynowej, stosując zróżnicowany skład fazy ruchomej z jednym lub z dwoma modyfikatorami w układzie fazy normalnej, w fazie odwróconej i w fazie organicznej. Jako modyfikatory w układzie faz normalnych stosowano mieszaninę n-heksanu z etanolem lub 2-propanolem, w układzie faz odwróconych wodę z acetonitrylem, a w polarnej fazie organicznej acetonitryl z kwasem octowym lub acetonitryl z kwasem octowym i trietyloaminą. Zamiana układu faz normalnych na fazy odwrócone spowodowała zmianę kolejności elucji badanych związków. W układzie faz normalnych mieszanina n-heksanu z etanolem powoduje lepsze rozdzielenie enancjomerów niż mieszanina n-heksanu z 2-propanolem. Retencja i enancjoselektywność zależą od pH fazy ruchomej w układzie faz odwróconych. Lepszą separację enancjomerów uzyskano przy niskim pH (ok. 3). Niewielki dodatek trietyloaminy jako drugiego modyfikatora zwiększył sprawność układu i wpłynął na rozdzielenie enancjomerów trzech badanych związków. Znaczący wpływ achiralnych modyfikatorów na rozdział enancjomeskazuje na występowanie silnie zróżnicowanych oddziaływań międzymolekularnych w badanych układach. Podobny wniosek można było wysnuć na podstawie analizy równań QSRR.

EN

Fifteen racemic derivatives of pyrrolidin-2-one were sepd. on a tri(3,5-dimethylphenylcarboilo)-β-cyclodextrin column by using n-hexane/EtOH or n-hexane/Me₂CHOH in normal mobile phases, H₂O/MeCN reversed phases and MeCN/AcOH or MeCN/AcOH/Et₃N org. phases. EtOH was more efficient than Me₂CHOH in normal phases. The addn. of Et₃N resulted in an improvement of sepn. in reversed phase, where the best results were achieved at pH 3.

9

Cosmetotextiles: State of Art

Singh M. K., Varun V K, Behera B K

Fibres & Textiles in Eastern Europe

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2011

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Vol. 19, no. 4 (87)

27--33

EN

The main aim of this article is to collect the scattered knowledge of Cosmetotextiles and present it to the world scientific community for scrutiny. Various aspects of Cosmetotextiles are compiled systematically and oriented towards product development. The technology of Cosmetotextiles is at the neonatal stage. The joint efforts of textile technologists, biochemists, cosmetic experts and medicos can achieve challenging targets in the field of Cosmetotextiles. Various derivatives of metals, plants and animals are used in pure and derivative form to generate cosmetic functionality in textiles. Various routes for the incorporation of cosmetic potentail in textiles are available, of which microencapsulation and the use of cyclodextrin as cage material are the most popular. The content of moisture on skin surface is a key parameter in maintaining skin elasticity and glowing potential. The characterization of Cosmetotextiles is a difficult task, but the Europeans have taken the lead by classifying and standardising the testing of the cosmetic effects of cosmetotextiles.

PL

Celem artykułu jest przedstawienie wiedzy rozrzuconej w różnych źródłach na temat nowo wprowadzonego pojęcia kosmotekstyliów. Przedstawiono podział kosmotekstyliów, kierunki możliwych aplikacji, stosowane zróżnicowane technologie dla otrzymania pożądanego efektu, środki wywołujące odpowiedni efekt wprowadzane do włókien przędz, tkanin lub dzianin oraz gotowych produktów. Opisano również stosowane sposoby badań i testów. Podano także liczne przykłady współcześnie stosowanych kosmotekstyliów.

10

Positron annihilation and speed of sound in the systems containing beta-cyclodextrin

Jerie K., Baranowski A., Burakowski A., Gliński J.

Nukleonika

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2010

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Vol. 55, No. 1

65-68

EN

Positron annihilation measurements were performed in aqueous solutions of beta-cyclodextrin, as well as in solid mixtures of this sugar with a long-chained alcohol, n-nonanol. Additionally, acoustic (sound speed, density and compressibility) experiments were done in aqueous beta-cyclodextrin and tert-butanol systems and in a three-component water-beta-cyclodextrin-tert-butanol system. The results show that in aqueous solution cyclodextrin does not form inclusive complexes with alcohol, while solid sugar-alcohol mixtures undergo slow changes in time, most probably caused by exchange of guest between interior and exterior of the host molecule.

11

Acoustical Spectroscopy of Carbohydrate Aqueous Solutions: Saccharides; Alkyl Glycosides; Cyclodextrins. Part II. Association and Complexation

Kaatze U.

Archives of Acoustics

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2010

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Vol. 35, No. 4

739-762

EN

Results from broadband acoustical spectroscopy for aqueous solutions of mono- and disaccharides with salts added, of various alkyl glycosides, and of α-cyclodextrin with n-octyl-β-D-glucopyranoside added are briefly summarized in view of their relevance in the study of molecular association and complexation processes. Mono- and tridentate complexes of alkali earth ions with saccharides are discussed as well as the monomer exchange between micellar structures and the suspending phase in the alkyl glycoside surfactant solutions. Particular attention is given to the behaviour at solute concentrations close to the critical micelle concentration or aggregate concentration, respectively. Also described is the competition between inclusion complex formation and self-aggregation in solutions containing cyclodextrin and alkyl glycoside surfactant.

12

Cyclodextrins as drug carriers

Mianowska B., Śliwa W.

Prace Naukowe. Chemia i Ochrona Środowiska / Akademia im. Jana Długosza w Częstochowie

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2008

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Vol. 12

155-162

EN

In the paper selected examples of cyclodextrin inclusion complexeswith drugs are presented, pointing out advantages of their encapsulation.

PL

W artykule przedstawiono wybrane przykłady kompleksów inkluzyjnych cyklodekstryn z lekami, podkreślając pozytywne zmiany właściwości leków spowodowane ich kompleksowaniem.

13

Differences between DeltaH and DeltaS Values of the 1:2 Complexes of Camphor Enantiomers with alfa-Cyclodextrin Determined by NMR Titrations and by Other Techniques

Dodziuk H., Kozminski W., Dolgonos G.

Polish Journal of Chemistry

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2003

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Vol. 77 / nr 2

251-255

EN

DeltaH12 andDeltaS12 values for the 1:2 complexes of camphor enantiomers with alfa-cyclodextrin by NMR titrations, carried out from 25 to 48 graduateC, yielded -16.0 +-0.2 kcal/mol and 28.3 0.3 e.u. for 1a@2 and -9.8 0.2 kcal/mol and 9.10.2 e.u. for 1b@2. A comparison of the values obtained by other groups, using isothermal titration calorimetry and reversed-phase liquid hromatography, showed considerable differences except the Delta H12 and DeltaS12 for 1a@2, obtained by NMR and ITC methods. The reason of the differences, involving RPLC, are not discussed in view of internal inconsistencies of this method. On the other hand, the disagreement between the ITC andNMRresults seems to be due to the difference in solvents (H2O and D2O, respectively) used in both methods, which causes deuteration of all 36 OH groups of the host cyclodextrins. Interestingly, the deuteration causes a lowering of the absolute values of DeltaH12 and DeltaS12 for 1b@2, while the corresponding values of the complex with the second enantiomer are either unchanged or undergo only small changes upon the complexation.

14

Textile slow-release systems with medical applications

ten Breteler M. R., Nierstrasz V. A., Warmoeskerken M. M. C. G.

Autex Research Journal

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2002

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Vol. 2, no. 4

175--189

EN

In the development of medical drug delivery systems, attention has been increasingly focused on slow- or controlled delivery systems in order to achieve an optimal therapeutic effect. Since the administration of drugs often requires a defined or minimum effective dosage in the human body, more conventional delivery systems such as tablets require relatively high doses, which can result in undesired toxic effects. Subsequent degradation of the drug in the human body will result in a drug concentration below the minimum effective level. Furthermore, there are situations where oral administration is less advisable, such as in cases of prolonged treatment or with people that are forgetful, which again results in ineffective treatment. Textile slow-release systems have the potential to overcome these negative aspects. Drugs containing transdermal patches for ex-vivo applications are already familiar; however, this paper will not deal with such applications, but with more advanced in-vivo textile slow-release systems. Due to enormous progress over the years in the fields of supramolecular chemistry, nanotechnology, and polymer science & technology, a number of promising drug delivery technologies have been developed. This review will focus on the opportunities of textiles bearing cyclodextrins, aza-crown ethers or fullerenes, as well as ion-exchange fibres, drug-loaded hollow fibres, textiles treated with nanoparticles and fibres with bioactive compounds in their embodiment. In this paper, the delivery systems will be discussed and compared in terms of biostability, biodegradability, controllability, toxicity, carcinogenicity, interface reactions, material costs and the fabrication process.

15

Cyklodekstryny jako modyfikatory rozdzielania amin i jonów nieorganicznych metodą elektroforezy kapilarnej

Maruszak W.

Analityka : nauka i praktyka

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2001

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nr 3

12--15

PL

Poznanie składu badanego materiału jest celem analizy chemicznej. Coraz większe wymagania stawiane analizie chemicznej stwarzają konieczność nieustannego rozwoju nowych, doskonalszych metod analizy. Do zestawu wysokosprawnych technik analitycznych od wielu już lat należy elektroforeza kapilarna.