MyMedR

Displaying publications 1 - 20 of 66 in total

Abstract:

Sort:

Fulltext A Comparative Study on Suitability of Model-Free and Model-Fitting Kinetic Methods to Non-Isothermal Degradation of Lignocellulosic Materials

Mahmood H, Shakeel A, Abdullah A, Khan MI, Moniruzzaman M

Polymers (Basel), 2021 Jul 29;13(15).
PMID: 34372105 DOI: 10.3390/polym13152504

The thermal kinetic modeling is crucial for development of sustainable processes where lignocellulosic fuels are a part of chemical system and their thermal degradation eventuates. In this paper, thermal decomposition of three lignocellulosic materials (bagasse, rice husk, and wheat straw) was obtained by the thermogravimetric (TG) technique and kinetics was analyzed by both model-fitting and isoconversional (model-free) methods to compare their effectiveness. Two models selected from each class include Arrhenius and Coats-Redfern (model-fitting), and Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO) (model-free). The formal model-fitting approach simulating the thermal decomposition of solids by assuming a fixed mechanism was found to be unduly facile. However, activation energy (E) values calculated from two model-fitting techniques were considerably different from each other with a percentage difference in the range of 1.36% to 7.65%. Particularly, both model-fitting methods predicted different reaction mechanism for thermal disintegration of lignocellulosic materials (two-dimensional diffusion (D2) by Arrhenius and one-dimensional diffusion (D1) by Coat-Redfern method). Conversely, the model-free routine offers a transformation of mechanism and activation energy values throughout reaction and is, therefore, more authentic to illustrate the complexity of thermal disintegration of lignocellulosic particles. Based on the model-free kinetic analysis, the lignocellulosic materials may be devised in following order of activation energy: rice husk > bagasse > wheat straw, by both KAS and FWO methods with a percentage difference no more than 0.84% for fractional conversion up to 0.7. Isoconversional approach could be recommended as more realistic and precise for modeling non-isothermal kinetics of lignocellulosic residues compared to model-fitting approach.
Fulltext A novel approach for pineapple leaf fiber processing as an ultimate fiber using existing machines

Jalil MA, Moniruzzaman M, Parvez MS, Siddika A, Gafur MA, Repon MR, et al.

Heliyon, 2021 Aug;7(8):e07861.
PMID: 34485740 DOI: 10.1016/j.heliyon.2021.e07861

This research aims to study the spinnability of pristine PALF and PALF blended cotton using the existing spinning machines. Apron draft ring spinning frame and flyer jute spinning frame were used to produce 100% PALF yarn and the yarns count were found 121 tex and 138 tex separately. Besides, 90:10 and 80:20 cotton-PALF blended 30 tex yarn spun in a cotton spinning system with different twist factors. With both yarns, two samples; 1/1 plain and 3/1 twill fabrics, were fabricated through equal density. For plain and twill fabric, PALF yarn of 121 tex and 138 tex were used in the warp way, respectively and PALF blended cotton yarn of 60 tex was used in the weft way. Through the study, physio-mechanical properties of the samples were explored and FTIR & XRD patterns were analyzed to perform the task for diversified use as an ultimate fiber in industrial and domestic purposes.
A simple, sensitive, and straightforward LC-MS approach for rapid analysis of three potential genotoxic impurities in rabeprazole formulations

Yenugu VMR, Ambavaram VBR, Moniruzzaman M, Madhavi G

J Sep Sci, 2018 Nov;41(21):3966-3973.
PMID: 30138541 DOI: 10.1002/jssc.201800626

In the present study, a sensitive and fully validated liquid chromatography with mass spectrometry method was developed for the quantification of three potential genotoxic impurities in rabeprazole drug substance. The separation was achieved on Symmetry C18 column (100 × 4.6 mm, 3.5 μm) using 0.1% formic acid in water as mobile phase A and acetonitrile as mobile phase B in gradient elution mode at 0.5 mL/min flow rate. Triple quadrupole mass detection with electrospray ionization was operated in selected ion recording mode for the quantification of impurities. The calibration curves were demonstrated good linearity over the concentration range of 1.0-4.5 ppm for O-phenylenediamine, 1.8-4.5 ppm for 4-nitrolutidine-N-oxide and 1.0-4.5 ppm for benzyltriethylammonium chloride with respect to 10 mg/mL of rabeprazole. The correlation coefficient obtained in each case was >0.998. The recoveries were found satisfactory over the range between 94.22 and 106.84% for all selected impurities. The method validation was carried out following International Conference on Harmonization guidelines, from which the developed method was able to quantitate the impurities at 1.0 ppm for O-phenylenediamine, 1.8 ppm for 4-nitrolutidine-N-oxide and 1.0 ppm for benzyltriethylammonium chloride. Furthermore, the proposed method was successfully evaluated for the determination of selected impurities from bulk drug and formulation samples of rabeprazole within the acceptable limits.
Advances in the analytical methods for determining the antioxidant properties of honey: a review

Moniruzzaman M, Khalil MI, Sulaiman SA, Gan SH

Afr J Tradit Complement Altern Med, 2012;9(1):36-42.
PMID: 23983317

Free radicals and reactive oxygen species (ROS) have been implicated in contributing to the processes of aging and disease. In an effort to combat free radical activity, scientists are studying the effects of increasing individuals' antioxidant levels through diet and dietary supplements. Honey appears to act as an antioxidant in more ways than one. In the body, honey can mop up free radicals and contribute to better health. Various antioxidant activity methods have been used to measure and compare the antioxidant activity of honey. In recent years, DPPH (Diphenyl-1-picrylhydrazyl), FRAP (Ferric Reducing Antioxidant Power), ORAC (The Oxygen Radical Absorbance Capacity), ABTS [2, 2-azinobis (3ehtylbenzothiazoline-6-sulfonic acid) diamonium salt], TEAC [6-hydroxy-2, 5, 7, 8-tetramethylchroman-2-carboxylic acid (Trolox)-equivalent antioxidant capacity] assays have been used to evaluate antioxidant activity of honey. The antioxidant activity of honey is also measured by ascorbic acid content and different enzyme assays like Catalase (CAT), Glutathione Peroxidase (GPO), Superoxide Dismutase (SOD). Among the different methods available, methods that have been validated, standardized and widely reported are recommended.
Aggregation, toxicity, and biodegradability study of an ionic liquid-based formulation for effective oil spill remediation

Nazar M, Ul Hassan Shah M, Ahmad A, Goto M, Zaireen Nisa Yahya W, Moniruzzaman M

Chemosphere, 2023 Dec;344:140412.
PMID: 37827466 DOI: 10.1016/j.chemosphere.2023.140412

Chemical dispersants are extensively used for marine oil spill remediation. However, the increased toxicity and low biodegradability of these dispersants restrict their employment in the marine environment. Hence, in this work, we have developed an eco-friendly formulation composed of an ionic liquid,1-butyl-3-methylimidazolium lauroyl sarcosinate [BMIM][Lausar] and sorbitan monooleate (Span) 80. Micellar and interfacial parameters, dispersion effectiveness, as well as the toxicity and biodegradability of the developed formulation were investigated. Micellar properties confirmed a high degree of synergism among the surfactant molecules and the formation of stable micelle. The dispersion effectiveness, at dispersant-to-oil ratio (DOR) of 1:25 (v/v), against three crude oils (Arab, Ratawi, and Doba) was assessed. We achieved a dispersion effectiveness of 68.49%, 74.05%, and 83.43% for Ratawi, Doba, and Arab crude oil, respectively, using a 70:30 (w/w) ratio of Span 80 to [BMIM][Lausar]. Furthermore, the results obtained from optical microscopy and particle size analysis (PSA) indicated that the oil droplet size decreased with higher DOR. Additionally, acute toxicity experiments were conducted on zebrafish (Danio rerio) using the developed formulation, confirming its non-toxic behavior, with LC50 values of 800 mg/L after 96 h. The formulation also exhibited high biodegradability, with only 25.01% of the original quantity remaining after 28 days. Hence, these results suggest that the new formulation has the potential to be a highly effective and environmentally friendly dispersant for oil spill remediation.
An Overview on the Toxicological Properties of Ionic Liquids toward Microorganisms

Sivapragasam M, Moniruzzaman M, Goto M

Biotechnol J, 2020 Apr;15(4):e1900073.
PMID: 31864234 DOI: 10.1002/biot.201900073

Ionic liquids (ILs), a class of materials with unique physicochemical properties, have been used extensively in the fields of chemical engineering, biotechnology, material sciences, pharmaceutics, and many others. Because ILs are very polar by nature, they can migrate into the environment with the possibility of inclusion in the food chain and bioaccumulation in living organisms. However, the chemical natures of ILs are not quintessentially biocompatible. Therefore, the practical uses of ILs must be preceded by suitable toxicological assessments. Among different methods, the use of microorganisms to evaluate IL toxicity provides many advantages including short generation time, rapid growth, and environmental and industrial relevance. This article reviews the recent research progress on the toxicological properties of ILs toward microorganisms and highlights the computational prediction of various toxicity models.
Assessment of dispersive liquid-liquid microextraction conditions for gas chromatography time-of-flight mass spectrometry identification of organic compounds in honey

Moniruzzaman M, Rodríguez I, Rodríguez-Cabo T, Cela R, Sulaiman SA, Gan SH

J Chromatogr A, 2014 Nov 14;1368:26-36.
PMID: 25441341 DOI: 10.1016/j.chroma.2014.09.057

The suitability of the dispersive liquid-liquid microextraction (DLLME) technique for gas chromatography (GC) characterization of minor organic compounds in honey samples is evaluated. Under optimized conditions, samples were pre-treated by liquid-liquid extraction with acetonitrile followed by DLLME using carbon tetrachloride (CCl4, 0.075 mL) as extractant. The yielded settled phase was analyzed by GC using high resolution time-of-flight (TOF) mass spectrometry (MS). The whole sample preparation process is completed in approximately 10 min, with a total consumption of organic solvents below 4 mL, relative standard deviations lower than 12% and with more than 70 organic compounds, displaying linear retention index in the range from 990 to 2900, identified in the obtained extracts. In comparison with HS SPME extraction, higher peak intensities were attained for most volatile and semi-volatile compounds amenable to both extraction techniques. Furthermore, other species such as highly polar and water soluble benzene acids, long chain fatty acids, esters and flavonoids, which are difficult to concentrate by HS SPME, could be identified in DLLME extracts. Some of the compounds identified in DLLME extracts have been proposed as useful for samples classification and/or they are recognized as markers of honeys from certain geographic areas.
Assessment of gas chromatography time-of-flight accurate mass spectrometry for identification of volatile and semi-volatile compounds in honey

Moniruzzaman M, Rodríguez I, Ramil M, Cela R, Sulaiman SA, Gan SH

Talanta, 2014 Nov;129:505-15.
PMID: 25127626 DOI: 10.1016/j.talanta.2014.06.019

The performance of gas chromatography (GC) combined with a hybrid quadrupole time-of-flight (QTOF) mass spectrometry (MS) system for the determination of volatile and semi-volatile compounds in honey samples is evaluated. After headspace (HS) solid-phase microextraction (SPME) of samples, the accurate mass capabilities of the above system were evaluated for compounds identification. Accurate scan electron impact (EI) MS spectra allowed discriminating compounds displaying the same nominal masses, but having different empirical formulae. Moreover, the use of a mass window with a width of 0.005 Da provided highly specific chromatograms for selected ions, avoiding the contribution of interferences to their peak areas. Additional information derived from positive chemical ionization (PCI) MS spectra and ion product scan MS/MS spectra permitted confirming the identity of novel compounds. The above possibilities are illustrated with examples of honey aroma compounds, belonging to different chemical classes and containing different elements in their molecules. Examples of compounds whose structures could not be described are also provided. Overall, 84 compounds, from a total of 89 species, could be identified in 19 honey samples from 3 different geographic areas in the world. The suitability of responses measured for selected ions, corresponding to above species, for authentication purposes is assessed through principal components analysis.
Fulltext Association of Arterial Stiffness and Atherosclerotic Burden With Brain Structural Changes Among Japanese Men

Azahar NM, Yano Y, Kadota A, Shiino A, Syaifullah AH, Miyagawa N, et al.

J Am Heart Assoc, 2023 Jun 06;12(11):e028586.
PMID: 37232267 DOI: 10.1161/JAHA.122.028586

Background Little is known regarding whether arterial stiffness and atherosclerotic burden are each independently associated with brain structural changes. Simultaneous assessments of both arterial stiffness and atherosclerotic burden in associations with brain could provide insights into the mechanisms of brain structural changes. Methods and Results Using data from the SESSA (Shiga Epidemiological Study of Subclinical Atherosclerosis), we analyzed data among 686 Japanese men (mean [SD] age, 67.9 [8.4] years; range, 46-83 years) free from history of stroke and myocardial infarction. Brachial-ankle pulse wave velocity and coronary artery calcification on computed tomography scans were measured between March 2010 and August 2014. Brain volumes (total brain volume, gray matter, Alzheimer disease signature and prefrontal) and brain vascular damage (white matter hyperintensities) were quantified using brain magnetic resonance imaging from January 2012 through February 2015. In multivariable adjustment models including mean arterial pressure, when brachial-ankle pulse wave velocity and coronary artery calcification were entered into the same models, the β (95% CI) for Alzheimer disease signature volume for each 1-SD increase in brachial-ankle pulse wave velocity was -0.33 (-0.64 to -0.02), and the unstandardized β (95% CI) for white matter hyperintensities for each 1-unit increase in coronary artery calcification was 0.68 (0.05-1.32). Brachial-ankle pulse wave velocity and coronary artery calcification were not statistically significantly associated with total brain and gray matter volumes. Conclusions Among Japanese men, higher arterial stiffness was associated with lower Alzheimer disease signature volumes, whereas higher atherosclerotic burden was associated with brain vascular damage. Arterial stiffness and atherosclerotic burden may be independently associated with brain structural changes via different pathways.
Binary mixture of ionic liquid and span 80 for oil spill remediation: Synthesis and performance evaluation

Nazar M, Ahmad A, Hussain SMS, Moniruzzaman M

Mar Pollut Bull, 2024 Apr 02;202:116311.
PMID: 38574502 DOI: 10.1016/j.marpolbul.2024.116311

The synthesis of new surfactants helps to mitigate the environmental and financial effects of oil spills by providing efficient cleanup options. Herein, this study provides the development of a binary mixture of Span 80 and Choline myristate [Cho][Mys], a surface-active ionic liquid (SAIL) as green dispersant for oil spill remediation. The synergistic interaction at a 60:40 (w/w) ratio significantly lowered the critical micelle concentration (cmc) to 0.029 mM. Dispersion efficiency tests with Arab crude oil showed optimal performance at a 60:40 ratio of Span 80 and [Cho][Mys] (1:25 dispersant to oil ratio, v/v), achieving 81.16 % dispersion effectiveness in the baffled flask test. The binary mixture demonstrated superior emulsion stability (6 h) and the lowest interfacial tension (1.12 mN/m). Acute toxicity experiments revealed the dispersant's practical non-toxicity with an LC50 value of 600 mg/L. Overall, this environmentally benign surfactant combination shows promise as a safe and effective oil spill dispersant.
Biocompatible Ionic Liquid-Mediated Micelles for Enhanced Transdermal Delivery of Paclitaxel

Ali MK, Moshikur RM, Wakabayashi R, Moniruzzaman M, Goto M

ACS Appl Mater Interfaces, 2021 May 05;13(17):19745-19755.
PMID: 33891816 DOI: 10.1021/acsami.1c03111

Chemotherapeutic cytotoxic agents such as paclitaxel (PTX) are considered essential for the treatment of various cancers. However, PTX injection is associated with severe systemic side effects and high rates of patient noncompliance. Micelle formulations (MFs) are nano-drug delivery systems that offer a solution to these problems. Herein, we report an advantageous carrier for the transdermal delivery of PTX comprising a new MF that consists of two biocompatible surfactants: cholinium oleate ([Cho][Ole]), which is a surface-active ionic liquid (SAIL), and sorbitan monolaurate (Span-20). A solubility assessment confirmed that PTX was readily solubilized in the SAIL-based micelles via multipoint hydrogen bonding and cation-π and π-π interactions between PTX and SAIL[Cho][Ole]. Dynamic light scattering (DLS) and transmission electron microscopy revealed that in the presence of PTX, the MF formed spherical PTX-loaded micelles that were well-distributed in the range 8.7-25.3 nm. According to DLS, the sizes and size distributions of the micelle droplets did not change significantly over the entire storage period, attesting to their physical stability. In vitro transdermal assessments using a Franz diffusion cell revealed that the MF absorbed PTX 4 times more effectively than a Tween 80-based formulation and 6 times more effectively than an ethanol-based formulation. In vitro and in vivo skin irritation tests revealed that the new carrier had a negligible toxicity profile compared with a conventional ionic liquid-based carrier. Based on these findings, we believe that the SAIL[Cho][Ole]-based MF has potential as a biocompatible nanocarrier for the effective transdermal delivery of poorly soluble chemotherapeutics such as PTX.
Fulltext Biocompatible and Biodegradable Surfactants from Orange Peel for Oil Spill Remediation

Wang PS, Ahmad A, Nazar M, Rahmah AU, Moniruzzaman M

Molecules, 2023 Aug 01;28(15).
PMID: 37570764 DOI: 10.3390/molecules28155794

Oil spill remediation plays a vital role in mitigating the environmental impacts caused by oil spills. The chemical method is one of the widely recognized approaches in chemical surfactants. However, the most commonly used chemical surfactants are toxic and non-biodegradable. Herein, two biocompatible and biodegradable surfactants were synthesized from orange peel using the ionic liquid 1-butyl-3-methylimidazolium chloride (BMIMCl) and organic solvent dimethylacetamide (CH3CN(CH3)2) as reaction media. The acronyms SOPIL and SOPOS refer to the surfactants prepared with BMIMCl and dimethylacetamide, respectively. The surface tension, dispersant effectiveness, optical microscopy, and emulsion stability test were conducted to examine the comparative performance of the synthesized surfactants. The Baffled flask test (BFT) was carried out to determine the dispersion effectiveness. The toxicity test was performed against zebrafish (Danio rerio), whereas the closed bottle test (CBT) evaluated biodegradability. The results revealed that the critical micelle concentration (CMC) value of SOPIL was lower (8.57 mg/L) than that of SOPOS (9.42 mg/L). The dispersion effectiveness values for SOPIL and SOPOS were 69.78% and 40.30%, respectively. The acute toxicity test demonstrated that SOPIL was 'practically non-toxic' with a median lethal concentration of more than 1000 mg/L after 96 h. The biodegradation rate was recorded as higher than 60% for both surfactants within 28 days, demonstrating their readily biodegradable nature. Considering these attributes, biocompatible and biodegradable surfactants derived from orange peel emerge as a promising and sustainable alternative for oil spill remediation.
Biocompatible ionic liquids assisted transdermal co-delivery of antigenic protein and adjuvant for cancer immunotherapy

Chowdhury MR, Moshikur RM, Wakabayashi R, Moniruzzaman M, Goto M

Int J Pharm, 2021 May 15;601:120582.
PMID: 33872711 DOI: 10.1016/j.ijpharm.2021.120582

Human skin contains numerous antigen-presenting cells that are a potential target for several immune-based therapies, including vaccination and cancer immunotherapy. However, the outermost layer of the skin-the stratum corneum-acts as a major physical barrier against the permeation of antigens that have a molecular weight > 500 Da. In this study, an ionic liquid-assisted delivery system (ILDS) was developed, which enabled the successful transdermal delivery of an antigenic protein, ovalbumin (OVA), with a toll-like receptor agonist, imiquimod, as an adjuvant, to stimulate a specific immune response. Both the ionic liquids and ILDS were completely biocompatible for topical or transdermal application for therapeutic purposes. The skin permeation of the antigenic protein and adjuvant was found to be significantly enhanced because of the incorporation of a surface-active ionic liquid in the ILDS. An in vivo immunization study showed that there was a high level of OVA-specific IgG antibody production because of the enhanced permeation of the antigen and adjuvant across and into the skin. In a preclusive anticancer study, vaccination through ILDS showed stronger tumor-growth inhibition compared to control group. These results indicated that the ILDS could be a promising strategy for transdermal immunization as future therapeutics.
Characterization and cytotoxicity evaluation of biocompatible amino acid esters used to convert salicylic acid into ionic liquids

Moshikur RM, Chowdhury MR, Wakabayashi R, Tahara Y, Moniruzzaman M, Goto M

Int J Pharm, 2018 Jul 30;546(1-2):31-38.
PMID: 29751143 DOI: 10.1016/j.ijpharm.2018.05.021

The technological utility of active pharmaceutical ingredients (APIs) is greatly enhanced when they are transformed into ionic liquids (ILs). API-ILs have better solubility, thermal stability, and the efficacy in topical delivery than solid or crystalline drugs. However, toxicological issue of API-ILs is the main challenge for their application in drug delivery. To address this issue, 11 amino acid esters (AAEs) were synthesized and investigated as biocompatible counter cations for the poorly water-soluble drug salicylic acid (Sal) to form Sal-ILs. The AAEs were characterized using 1H and 13C NMR, FTIR, elemental, and thermogravimetric analyses. The cytotoxicities of the AAE cations, Sal-ILs, and free Sal were investigated using mammalian cell lines (L929 and HeLa). The toxicities of the AAE cations greatly increased with inclusion of long alkyl chains, sulfur, and aromatic rings in the side groups of the cations. Ethyl esters of alanine, aspartic acid, and proline were selected as a low cytotoxic AAE. The cytotoxicities of the Sal-ILs drastically increased compared with the AAEs on incorporation of Sal into the cations, and were comparable to that of free Sal. Interestingly, the water miscibilities of the Sal-ILs were higher than that of free Sal, and the Sal-ILs were miscible with water at any ratio. A skin permeation study showed that the Sal-ILs penetrated through skin faster than the Sal sodium salt. These results suggest that AAEs could be used in biomedical applications to eliminate the use of traditional toxic solvents for transdermal delivery of poorly water-soluble drugs.
Fulltext Chemical and structural changes of pretreated empty fruit bunch (EFB) in ionic liquid-cellulase compatible system for fermentability to bioethanol

Elgharbawy AA, Alam MZ, Moniruzzaman M, Kabbashi NA, Jamal P

3 Biotech, 2018 May;8(5):236.
PMID: 29744268 DOI: 10.1007/s13205-018-1253-8

The pretreatment of empty fruit bunch (EFB) was conducted using an integrated system of IL and cellulases (IL-E), with simultaneous fermentation in one vessel. The cellulase mixture (PKC-Cel) was derived from Trichoderma reesei by solid-state fermentation. Choline acetate [Cho]OAc was utilized for the pretreatment due to its biocompatibility and biodegradability. The treated EFB and its hydrolysate were characterized by the Fourier transform infrared spectroscopy, scanning electron microscopy, and chemical analysis. The results showed that there were significant structural changes in EFB after the treatment in IL-E system. The sugar yield after enzymatic hydrolysis by the PKC-Cel was increased from 0.058 g/g of EFB in the crude sample (untreated) to 0.283 and 0.62 ± 06 g/g in IL-E system after 24 and 48 h of treatment, respectively. The EFB hydrolysate showed the eligibility for ethanol production without any supplements where ethanol yield was 0.275 g ethanol/g EFB in the presence of the IL, while lower yield obtained without IL-pretreatment. Moreover, it was demonstrated that furfural and phenolic compounds were not at the level of suppressing the fermentation process.
Choline and amino acid based biocompatible ionic liquid mediated transdermal delivery of the sparingly soluble drug acyclovir

Islam MR, Chowdhury MR, Wakabayashi R, Tahara Y, Kamiya N, Moniruzzaman M, et al.

Int J Pharm, 2020 May 30;582:119335.
PMID: 32311469 DOI: 10.1016/j.ijpharm.2020.119335

Transdermal delivery of drugs is more challenging for drugs that are insoluble or sparingly soluble in water and most organic solvents. To overcome this problem, ionic liquid (IL)-mediated ternary systems have been suggested as potential drug carriers. Here, we report potent ternary (IL-EtOH-IPM) systems consisting of biocompatible ILs, ethanol (EtOH), and isopropyl myristate (IPM) that can dissolve a significant amount of the sparingly soluble drug acyclovir (ACV). The ternary systems were optically transparent and thermodynamically stable with a wide range of IL pertinence. An in vitro drug permeation study showed that the ILs in the ternary systems dramatically enhanced ACV permeation into and across the skin. Fourier Transform Infrared spectroscopy of the stratum corneum (sc) after treatment with ternary systems showed that the skin barrier function was reduced by disturbance of the regularly ordered arrangement of corneocytes and modification of the surface properties of the sc during permeation. Histological analysis, and skin irritation studies using a reconstructed human epidermis model showed the safety profile of the ternary system, and there were no significant changes in the structures of the sc, epidermis, and dermis. Therefore, ternary systems containing biocompatible ILs are promising for transdermal delivery of insoluble or sparingly soluble drugs.
Fulltext Cross-Linked Ionic Liquid Polymer for the Effective Removal of Ionic Dyes from Aqueous Systems: Investigation of Kinetics and Adsorption Isotherms

Reddy AVB, Rafiq R, Ahmad A, Maulud AS, Moniruzzaman M

Molecules, 2022 Nov 11;27(22).
PMID: 36431876 DOI: 10.3390/molecules27227775

In the current study, we have synthesized an imidazolium based cross-linked polymer, namely, 1-vinyl-3-ethylimidazolium bis(trifluoromethylsulfonyl)imide (poly[veim][Tf2N]-TRIM) using trimethylolpropane trimethacrylate as cross linker, and demonstrated its efficiency for the removal of two extensively used ionic dyes—methylene blue and orange-II—from aqueous systems. The detailed characterization of the synthesized poly[veim][Tf2N]-TRIM was performed with the help of 1H NMR, TGA, FT-IR and FE-SEM analysis. The concentration of dyes in aqueous samples before and after the adsorption process was measured using an UV-vis spectrophotometer. The process parameters were optimised, and highest adsorption was obtained at a solution pH of 7.0, adsorbent dosage of 0.75 g/L, contact time of 7 h and dye concentrations of 100 mg/L and 5.0 mg/L for methylene blue and orange-II, respectively. The adsorption kinetics for orange-II and methylene blue were well described by pseudo-first-order and pseudo−second-order models, respectively. Meanwhile, the process of adsorption was best depicted by Langmuir isotherms for both the dyes. The highest monolayer adsorption capacities for methylene blue and orange-II were found to be 1212 mg/g and 126 mg/g, respectively. Overall, the synthesized cross-linked poly[veim][Tf2N]-TRIM effectively removed the selected ionic dyes from aqueous samples and provided >90% of adsorption efficiency after four cycles of adsorption. A possible adsorption mechanism between the synthesised polymeric adsorbent and proposed dyes is presented. It is further suggested that the proposed ionic liquid polymer adsorbent could effectively remove other ionic dyes and pollutants from contaminated aqueous systems.
Fulltext Determination of carbamate and organophosphorus pesticides in vegetable samples and the efficiency of gamma-radiation in their removal

Chowdhury MA, Jahan I, Karim N, Alam MK, Abdur Rahman M, Moniruzzaman M, et al.

Biomed Res Int, 2014;2014:145159.
PMID: 24711991 DOI: 10.1155/2014/145159

In the present study, the residual pesticide levels were determined in eggplants (Solanum melongena) (n = 16), purchased from four different markets in Dhaka, Bangladesh. The carbamate and organophosphorus pesticide residual levels were determined by high performance liquid chromatography (HPLC), and the efficiency of gamma radiation on pesticide removal in three different types of vegetables was also studied. Many (50%) of the samples contained pesticides, and three samples had residual levels above the maximum residue levels determined by the World Health Organisation. Three carbamates (carbaryl, carbofuran, and pirimicarb) and six organophosphates (phenthoate, diazinon, parathion, dimethoate, phosphamidon, and pirimiphos-methyl) were detected in eggplant samples; the highest carbofuran level detected was 1.86 mg/kg, while phenthoate was detected at 0.311 mg/kg. Gamma radiation decreased pesticide levels proportionately with increasing radiation doses. Diazinon, chlorpyrifos, and phosphamidon were reduced by 40-48%, 35-43%, and 30-45%, respectively, when a radiation strength of 0.5 kGy was utilized. However, when the radiation dose was increased to 1.0 kGy, the levels of the pesticides were reduced to 85-90%, 80-91%, and 90-95%, respectively. In summary, our study revealed that pesticide residues are present at high amounts in vegetable samples and that gamma radiation at 1.0 kGy can remove 80-95% of some pesticides.
Fulltext Determination of heavy metals in the soils of tea plantations and in fresh and processed tea leaves: an evaluation of six digestion methods

Rashid MH, Fardous Z, Chowdhury MA, Alam MK, Bari ML, Moniruzzaman M, et al.

Chem Cent J, 2016;10:7.
PMID: 26900397 DOI: 10.1186/s13065-016-0154-3

BACKGROUND: The aim of this study was to determine the levels of cadmium (Cd), chromium (Cr), lead (Pb), arsenic (As) and selenium (Se) in (1) fresh tea leaves, (2) processed (black) tea leaves and (3) soils from tea plantations originating from Bangladesh.
METHODS: Graphite furnace atomic absorption spectrometry (GF-AAS) was used to evaluate six digestion methods, (1) nitric acid, (2) nitric acid overnight, (3) nitric acid-hydrogen peroxide, (4) nitric-perchloric acid, (5) sulfuric acid, and (6) dry ashing, to determine the most suitable digestion method for the determination of heavy metals in the samples.
RESULTS: The concentration ranges of Cd, Pb, As and Se in fresh tea leaves were from 0.03-0.13, 0.19-2.06 and 0.47-1.31 µg/g, respectively while processed tea contained heavy metals at different concentrations: Cd (0.04-0.16 µg/g), Cr (0.45-10.73 µg/g), Pb (0.07-1.03 µg/g), As (0.89-1.90 µg/g) and Se (0.21-10.79 µg/g). Moreover, the soil samples of tea plantations also showed a wide range of concentrations: Cd (0.11-0.45 µg/g), Pb (2.80-66.54 µg/g), As (0.78-4.49 µg/g), and Se content (0.03-0.99 µg/g). Method no. 2 provided sufficient time to digest the tea matrix and was the most efficient method for recovering Cd, Cr, Pb, As and Se. Methods 1 and 3 were also acceptable and can be relatively inexpensive, easy and fast. The heavy metal transfer factors in the investigated soil/tea samples decreased as follows: Cd > As > Se > Pb.
CONCLUSION: Overall, the present study gives current insights into the heavy metal levels both in soils and teas commonly consumed in Bangladesh.
Fulltext Determination of mineral, trace element, and pesticide levels in honey samples originating from different regions of Malaysia compared to manuka honey

Moniruzzaman M, Chowdhury MA, Rahman MA, Sulaiman SA, Gan SH

Biomed Res Int, 2014;2014:359890.
PMID: 24982869 DOI: 10.1155/2014/359890

The present study was undertaken to determine the content of six minerals, five trace elements, and ten pesticide residues in honeys originating from different regions of Malaysia. Calcium (Ca), magnesium (Mg), iron (Fe), and zinc (Zn) were analyzed by flame atomic absorption spectrometry (FAAS), while sodium (Na) and potassium (K) were analyzed by flame emission spectrometry (FAES). Trace elements such as arsenic (As), lead (Pb), cadmium (Cd), copper (Cu), and cobalt (Co) were analyzed by graphite furnace atomic absorption spectrometry (GFAAS) following the microwave digestion of honey. High mineral contents were observed in the investigated honeys with K, Na, Ca, and Fe being the most abundant elements (mean concentrations of 1349.34, 236.80, 183.67, and 162.31 mg/kg, resp.). The concentrations of the trace elements were within the recommended limits, indicating that the honeys were of good quality. Principal component analysis reveals good discrimination between the different honey samples. The pesticide analysis for the presence of organophosphorus and carbamates was performed by high performance liquid chromatography (HPLC). No pesticide residues were detected in any of the investigated honey samples, indicating that the honeys were pure. Our study reveals that Malaysian honeys are rich sources of minerals with trace elements present within permissible limits and that they are free from pesticide contamination.

Filters

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links