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Cationic Gemini Surfactants as Genes and Drug Carriers
Published in Yasser Shahzad, Syed A.A. Rizvi, Abid Mehmood Yousaf, Talib Hussain, Drug Delivery Using Nanomaterials, 2022
Mays Al-Dulaymi, Anas El-Aneed, Ildiko Badea
The tendency of gemini surfactants to interact with different kinds of active pharmaceutical ingredients along with their improved tissue permeability and enhanced residence time at the therapeutic target site make gemini surfactants favorable drug delivery candidates (Sanan et al. 2014; Sharma, Nandni, et al. 2014; Mahajan and Mahajan 2013). Casal-Dujat et al. highlighted the potential of bis-imidazolium gemini surfactants as nano carriers by investigating their ability to solubilize an anionic model drug, valproate (Casal-Dujat et al. 2013). Assessment of the interaction between the micelles and the drug indicated a progressive decrease in the self-diffusion coefficient of micelles as a function of an elevated drug concentration, providing insights about the solubility of the valproate (Casal-Dujat et al. 2013). The interaction of promethazine hydrochloride, an amphiphilic phenothiazine tranquilizer, with the pyridinium gemini surfactants was thoroughly evaluated (Mahajan et al. 2012). Results shown a cation-π interactions and hydrophobic interactions between the drug and gemini surfactants (Mahajan et al. 2012). Furthermore, it revealed a synergism in the mixed micelles system and spontaneity of the adsorption process (Mahajan et al. 2012).
Sustainable Biochar Derived from Agricultural Wastes for Removal of Methylene Green 5 from Aqueous Solution: Adsorption Kinetics, Isotherms, Thermodynamics, and Mechanism Analysis
Published in Tushar Kanti Sen, Air, Gas, and Water Pollution Control Using Industrial and Agricultural Solid Wastes Adsorbents, 2017
Hai Nguyen Tran, Sheng-Jie You, Huan-Ping Chao, Ya-Fen Wang
Methylene green 5 (MG5) is a cationic phenothiazine dye and heterocyclic aromatic chemical compound that can be considered as a nitro derivative of methylene blue. MG5 can be classed as a nitro-aromatic contaminant because it contains polar nitro-functional groups. In addition, MG5—commonly used in various industries—shows considerable solubility in both polar organic media and water. The investigation of MG5 adsorption onto various kinds of adsorbents has been published in the literature. These adsorbents were comprised of (1) pristine biosorbents derived from coconut shell (CC), orange peel (OP), and golden shower pod (GS) (Tran et al., 2017f); (2) hydrochars prepared from CC, OP, GS, and commercial glucose through hydrothermal carbonization (Tran et al., 2017a, 2017e); (3) activated carbons synthesized from OP, GS, and commercial saccharide precursors (i.e., glucose, xylose, and sucrose) (Huang et al., 2014; Tran et al., 2017d); (4) commercial activated carbons (Huang et al., 2014; Tran et al., 2017b); (5) hydrochar and activated carbon functionalized with triethylenetetramine (Tran et al., 2017a); and (6) others (i.e., silver and zinc oxide nanostructures loaded on activated carbons, mesoporous zeolite, and collagen-g-poly(acrylamide-co-maleic anhydride) hydrogel nanocomposite) (Lee et al., 2007; Marandi et al., 2013; Ghaedi et al., 2014). However, the capacity and mechanism of MG5 adsorption onto agricultural waste-derived biochar have not yet been investigated or presented in the scientific literature.
Chemistry of the Poly(alkylene oxide)s
Published in F. E. Bailey, Joseph V. Koleske, Alkylene Oxides and Their Polymers, 2020
F. E. Bailey, Joseph V. Koleske
Polyethers are susceptible to oxidation and usually are stabilized with an antioxidant. The oxidative attack of polyoxyethylene proceeds by an autooxidation mechanism that involves intrachain hydroperoxide formation, which decomposes and causes chain cleavage (117-119). The process is accelerated by ultraviolet light, strong acids, heavy metal ions (120), and certain oxidizing agents. McGary (117) investigated the attack inaqueous solution and found allyl, ethyl, and isopropyl alcohol to be effective stabilizers, with 2—5 percent isopropanol being particularly effective. In ethanol solution, no degradation was observed, and polymers precipitated from ethanol did not undergo chain scission at temperatures above 150°C (121). The investigation, which involved degradation in solution and in bulk, found that free-radical inhibitors had little effect, but the antioxidant, 2,4-di-t-butyl cresol, did retard decomposition in bulk and ethanol was effective in benzene solution. Additive systems consisting of 2,2’methylenebis(4-methyl-6-t-butyl phenol) and 2,6-di-t-butyl p-cresol (122) and phenothiazine or alkylpheno- thiazine and certain boron compounds (123) were found to be particularly effective stabilizers. Carbamates (124) and various phenols and cresols (125) have also been used. Other oxidative and thermal stabilizers for polyoxyethylene include piperazine and derivatives (126) and 2-mercaptoimidazoline and related compounds (127). Goldschmidt and coworkers (128) indicate that mixtures of aliphatic amines and phenolic compounds with at least two hydroxyl groups on the aromatic ring are good oxidative stabilizers. The aromatic compounds are the primary inhibitors and include hydroquinone, 1,2- and 1,4-dihydroxy naphthalene, di-t-butyl resorcinol, and similar compounds. The aliphatic amines are secondary inhibitors and include ethanolamine, isopropanolamine, ethylene diamine, etc.
Interaction of promethazine hydrochloride with TX-165 in aqueous, NaCl and urea media: a tensiometry and FTIR analysis
Published in Molecular Physics, 2023
M. Alfakeer, Malik Abdul Rub, Naved Azum, Anish Khan, Hadi M. Marwani, Khalid A. Alamry, Abdullah M. Asiri
Several amphiphilic drugs, at higher concentrations, also form micellar structures in an analogous way to a conventional surfactant [21–23]. Due to the high cmc of pure amphiphilic drugs, their self-association analysis for any intention is generally out of focus owing to the high quantity of the drug used, which might result in numerous side effects [24]. It is therefore common to use amphiphilic drugs in conjugation with carriers like nonionic surfactants, which usually form mixed micelles [21,25]. The cmc value of the mixture was reduced more than ten times, resulting in a very small amount of drug used for any application as well as it is possible to boost the absorption of many drugs using it in combination with a carrier such as surfactant (mixed micellar system) [25]. The amphiphilic tricyclic phenothiazine promethazine hydrochloride (PMT) consists of two main portions: one is the tail that has tricyclic large rigid hydrophobic ring, and the other one is the head that has an alkyl amine, which undergoes association, but at higher concentration (Figure 1) [21,25,26]. Among its uses are anticholinergics, sedatives, analgesics, antihistaminic, along with antipsychotics. The drug PMT is protonated (cationic) at low pH levels (lower than 7) but deprotonated at higher pH levels (over 7) [27]. Besides their usefulness, this drug also had some undesirable effects. Therefore, surface tension and FTIR measurements were used to study the interaction of PMT in different media with TX-165 (Figure 2) as the drug carrier to reduce PMT's unwanted effect.
Multivariate comparison of photocatalytic properties of thirteen nanostructured metal oxides for water purification
Published in Journal of Environmental Science and Health, Part A, 2019
Jakub Trawiński, Robert Skibiński
Amongst the studied pharmaceuticals, phenothiazine derivatives were marked by the shortest half-lives (Table 3), to such an extent, that some of them were undetectable after 10 min of the experiments (chlorpromazine and fluphenazine). The other – promazine, thioridazine and, possessing similar structure, chlorprothixene – had 10 to 20 min half-lives. Rapid photodegradation of those substances should be attributed to their high susceptibility to the direct photolysis. In fact their half-lives were sometimes lower in the ultrapure water experiment than in any of the photocatalytic ones (e.g. moclobemide). Slightly lower degradation rates were observed in the case of doxepin, fluvoxamine, olanzapine, fluoxetine, paroxetine and amisulpride (half-lives 10–40 min).
Comparative Evaluation of Cavities Disinfected with Ozone Gas and Photodynamic Therapy and Restored with Two Different Reinforced Glass Ionomer Cements on Microleakage and Color Change
Published in Ozone: Science & Engineering, 2022
Antimicrobial photodynamic therapy (PDT) is a new technique assumed to control dental caries successfully. The photo-activated disinfection is used in combination with the light of a wavelength and a photosensitizer fluid, which produces single oxygen and other radical species to remove microorganisms from dentin tubules, ensuring rapid and selective destruction of target cells (Raghavendra, Koregol, and Bhola 2009). Phenothiazine-based dyes such as Toluidine Blue, Methylene Blue, and Malachite Green are currently the most commonly used photosensitizers in PDT (Carvalho et al. 2011; Garcez et al. 2008; Nunes et al. 2011). However, because they are dyes, these photosensitizers may change the color of the tooth structure (Carvalho et al. 2011).