MyMedR

Displaying publications 21 - 40 of 256 in total

Abstract:

Sort:

Effect of short-chain alcohols on the physicochemical properties of d-phenothrin emulsions and their insecticidal activity against Aedes aegypti

Mohsin SMN, Hasan ZAA

Colloids Surf B Biointerfaces, 2023 Jan;221:113025.
PMID: 36403417 DOI: 10.1016/j.colsurfb.2022.113025

Oil-in-water (o/w) emulsion is utilized as an insecticide delivery system for mosquito control. However, evaporation inhibition adjuvant is needed to prevent fog drift, inhibit release of insecticidal actives and prolong suspension time. In the current study, we evaluated the effect of different short-chain alcohols, namely, propylene glycol, 1,3-propanediol, glycerol and crude glycerol, as adjuvants on the physicochemical properties of d-phenothrin o/w emulsion system. The bioactivity of optimized formulations containing 20 wt% glycerol (D1), 20 wt% propylene glycol (D2) and without added alcohol (negative control) were tested against larvae, pupae and adult Aedes aegypti (Ae. aegypti). It was found that propylene glycol produced smaller droplets at lower concentrations but poor long-term stability at higher concentrations, whereas glycerol had an appreciable effect on initial droplet size and stability with increasing concentration. According to the dose-response bioassays and room size chamber testing, the highest larvicidal, pupicidal and adulticidal activities were observed with D2, followed by D1 and negative control. Overall, the above study demonstrated improved emulsion stabilities and potency against Ae. aegypti larvae, pupae and adults using glycerol as adjuvant for effective mosquito control.

Matched MeSH terms: Emulsions/pharmacology
Fulltext Development and Evaluation of Self-Emulsifying Drug-Delivery System-Based Tablets for Simvastatin, a BCS Class II Drug

Bashir MA, Khan A, Shah SI, Ullah M, Khuda F, Abbas M, et al.

Drug Des Devel Ther, 2023;17:261-272.
PMID: 36726738 DOI: 10.2147/DDDT.S377686

BACKGROUND: Self-emulsifying drug-delivery systems (SEDDSs) are designed to improve the oral bioavailability of poorly water-soluble drugs. This study aimed at formulating and characterization of SEDDS-based tablets for simvastatin using castor and olive oils as solvents and Tween 60 as surfactant.
METHODS: The liquids were adsorbed on microcrystalline cellulose, and all developed formulations were compressed using 10.5 mm shallow concave round punches.
RESULTS: The resulting tablets were evaluated for different quality-control parameters at pre- and postcompression levels. Simvastatin showed better solubility in a mixture of oils and Tween 60 (10:1). All the developed formulations showed lower self-emulsification time (˂200 seconds) and higher cloud point (˃60°C). They were free of physical defects and had drug content within the acceptable range (98.5%-101%). The crushing strength of all formulations was in the range of 58-96 N, and the results of the friability test were within the range of USP (≤1). Disintegration time was within the official limits (NMT 15 min), and complete drug release was achieved within 30 min.
CONCLUSION: Using commonly available excipients and machinery, SEDDS-based tablets with better dissolution profile and bioavailability can be prepared by direct compression. These S-SEDDSs could be a better alternative to conventional tablets of simvastatin.

Matched MeSH terms: Emulsions/chemistry
Synergistic effect of hydrophilic polyglycerol fatty acid esters and protein on the stability of interfacial membrane in low-fat aerated emulsions with different homogenization conditions

Han W, Chai X, Zaaboul F, Sun Y, Tan CP, Liu Y

Food Chem, 2024 Mar 01;435:137584.
PMID: 37774617 DOI: 10.1016/j.foodchem.2023.137584

This study investigates the impact of various chain lengths of hydrophilic polyglycerol fatty acid esters (HPGEs), namely SWA-10D, M-7D and M-10D on protein interactions and their influence on the surface morphology and interfacial properties of low-fat aerated emulsions under different pressures conditions. M-7D and M-10D samples exhibited larger particle sizes, higher ζ-potential and rougher surface compared to SWA-10D sample at 1 % concentration of HPGEs. Consequently, M-7D and M-10D samples demonstrated lower values of G', G'', and higher values tan δ at the oil-water interface as pressure increased, thereby promoting the formation of less viscoelastic structures. M-7D sample, characterized by lower content of α-helix structures, resulted in an observable redshift in the NH and CO groups of the protein. Molecular docking analysis affirmed that M-7D sample exhibited a lower absolute binding energy value, indicating stronger interaction with the protein compared to other samples, ultimately contributing to the unstable interfacial membrane formed.

Matched MeSH terms: Emulsions/chemistry
Recent developments in improving the emulsifying properties of chitosan

Yang Y, Gupta VK, Amiri H, Pan J, Aghbashlo M, Tabatabaei M, et al.

Int J Biol Macromol, 2023 Jun 01;239:124210.
PMID: 37001778 DOI: 10.1016/j.ijbiomac.2023.124210

Chitosan is one of the valuable products obtained from crustacean waste. The unique characteristics of chitosan (antimicrobial, antioxidant, anticancer, and anti-inflammatory) have increased its application in various sectors. Besides unique biological properties, chitosan or chitosan-based compounds can stabilize emulsions. Nevertheless, studies have shown that chitosan cannot be used as an efficient stabilizer because of its high hydrophilicity. Hence, this review aims to provide an overview of recent studies dealing with improving the emulsifying properties of chitosan. In general, two different approaches have been reported to improve the emulsifying properties of chitosan. The first approach tries to improve the stabilization property of chitosan by modifying its structure. The second one uses compounds such as polysaccharides, proteins, surfactants, essential oils, and polyphenols with more wettability and emulsifying properties than chitosan's particles in combination with chitosan to create complex particles. The tendency to use chitosan-based particles to stabilize Pickering emulsions has recently increased. For this reason, more studies have been conducted in recent years to improve the stabilizing properties of chitosan-based particles, especially using the electrostatic interaction method. In the electrostatic interaction method, numerous research has been conducted on using proteins and polysaccharides to increase the stabilizing property of chitosan.

Matched MeSH terms: Emulsions/chemistry
Effects of limited enzymatic hydrolysis and polysaccharide addition on the physicochemical properties of emulsions stabilized with duck myofibrillar protein under low-salt conditions

He S, Li M, Sun Y, Pan D, Zhou C, Lan H

Food Chem, 2024 Jan 01;430:137053.
PMID: 37549626 DOI: 10.1016/j.foodchem.2023.137053

This study aimed to investigate the role of hydrolysis and guar gum (GG) participation on the emulsification of the duck myofibrillar protein (MP) and the related stability of oil-in-water emulsion in low-salt condition. Emulsions were prepared using one of each or both treatments, and that prepared with trypsin hydrolysis and GG (T-GG) exhibited the highest stability. FTIR analysis confirmed the hydrogen bond interactions between the system components. T-GG treatment improved emulsion properties and decreased oil droplet size. Moreover, CLSM indicated that aggregation of T-GG oil droplets was prevented. Physical stability was assessed such as Turbiscan stability index, creaming index, and rheological properties. The adsorbed percentage for T-GG was the lowest. However, interfacial tension, droplet size, stability, and peroxide value analyses indicated that a denser interfacial membrane structure is formed with T-GG. Thus, T-GG treatment could be applied in the food industry, such as in nutrient delivery systems and fat mimetics.

Matched MeSH terms: Emulsions/chemistry
The roles of ceramides and multivesicular emulsion (MVE) technology in atopic dermatitis: a narrative review

Chng CC

Med J Malaysia, 2024 Jan;79(1):85-94.
PMID: 38287763

INTRODUCTION: Atopic dermatitis (AD) is a highly prevalent chronic inflammatory skin condition. In Malaysia, a prevalence of 13.4% was reported for children between one and six years of age, one of the highest prevalence rates of AD in Asia. Many guidelines recommended moisturisers as the mainstay of treatment strategy for AD. Selecting an effective and suitable moisturiser for people with AD plays a crucial role in avoiding acute exacerbation of AD and achieving remission.
MATERIALS AND METHODS: Given that an array of active ingredients and topical vehicles for moisturisers are available in the market, this review summarised the roles of ceramides and multivesicular emulsion (MVE) technology in managing AD to help guide treatment decisions.
RESULTS: Ceramides are essential in maintaining the skin permeability barrier and hydration, modulating skin immunity through anti-inflammatory and antimicrobial defence system, and regulating cellular functions. Low levels and altered structures and composition of ceramides, compromised skin permeability barrier and increased transepidermal water loss were commonly observed in AD patients. Most clinical studies have shown that ceramidedominant moisturisers are safe and effective in adults and children with AD. MVE technology offers an attractive delivery system to replenish ceramides in the SC, repairing the compromised skin permeability barrier and potentially improving patient compliance.
CONCLUSION: Recommending clinically proven therapeutic moisturisers with the right ingredients (level, ratio, structure and composition), alongside an effective sustained release delivery system, to AD patients is one key strategy to successful disease control and flare prevention, subsequently reducing the disease burden to patients, families and societies.

Matched MeSH terms: Emulsions/therapeutic use
Fulltext Preparation and characterization of a curcumin nanoemulsion gel for the effective treatment of mycoses

Al Fatease A, Alqahtani A, Khan BA, Mohamed JMM, Farhana SA

Sci Rep, 2023 Dec 20;13(1):22730.
PMID: 38123572 DOI: 10.1038/s41598-023-49328-2

Fungal infections of skin including mycoses are one of the most common infections in skin or skins. Mycosis is caused by dermatophytes, non-dermatophyte moulds and yeasts. Various studies show different drugs to treat mycoses, yet there is need to treat it with applied drugs delivery. This study was designed to prepare a bio curcumin (CMN) nanoemulsion (CMN-NEs) for transdermal administration to treat mycoses. The self-nanoemulsification approach was used to prepare a nanoemulsion (NE), utilizing an oil phase consisting of Cremophor EL 100 (Cre EL), glyceryl monooleate (GMO), and polyethylene glycol 5000 (PEG 5000). Particle size (PS), polydispersity index (PDI), zeta potential (ZP), Fourier transform infrared (FTIR) spectrophotometric analysis, and morphological analyses were performed to evaluate the nanoemulsion (NE). The in vitro permeation of CMN was investigated using a modified vertical diffusion cell with an activated dialysis membrane bag. Among all the formulations, a stable, spontaneously produced nanoemulsion was determined with 250 mg of CMN loaded with 10 g of the oil phase. The average droplet size, ZP, and PDI of CMN-NEs were 90.0 ± 2.1 nm, - 7.4 ± 0.4, and 0.171 ± 0.03 mV, respectively. The release kinetics of CMN differed from zero order with a Higuchi release profile as a result of nanoemulsification, which also significantly increased the flux of CMN permeating from the hydrophilic matrix gel. Overall, the prepared nanoemulsion system not only increased the permeability of CMN but also protected it against chemical deterioration. Both CMN-ME (24.0 ± 0.31 mm) and CMN-NE gel (29.6 ± 0.25 mm) had zones of inhibition against Candida albicans that were significantly larger than those of marketed Itrostred gel (21.5 ± 0.34 mm). The prepared CMN-NE improved the bioavailability, better skin penetration, and the CMN-NE gel enhanced the release of CMN from the gel matrix on mycotic patients.

Matched MeSH terms: Emulsions/pharmacology
Fulltext Topical Nanoemulsion Hydrogel Formulated from Supercritical Fluid Extracted Palm-Pressed Fiber Oil and Virgin Coconut Oil with Antioxidant and Antibacterial Effects

Mah SH, Sundrasegaran S, Lau HLN

J Oleo Sci, 2024;73(4):489-502.
PMID: 38556283 DOI: 10.5650/jos.ess23197

Skincare industries are growing rapidly around the globe but most products are formulated using synthetic chemicals and organic solvent extracted plant extracts, thus may be hazardous to the users and incur higher cost for purification that eventually leads to phytonutrient degradation. Therefore, this study aimed to formulate a stable natural formulation with antioxidant and antimicrobial activities by using supercritical carbon dioxide (SC-CO 2 ) extracted palm-pressed fiber oil (PPFO) as an active ingredient with virgin coconut oil (VCO) as a formulation base. PPFO was extracted from fresh palm-pressed fiber (PPF) while VCO was from dried grated coconut copra using SC-CO 2 before being subjected to the analyses of physicochemical properties, phytonutrient content and biological activities including antioxidant and antimicrobial. The nanoemulgel formulations were then developed and examined for their stability through accelerated stability study for 3 months by measuring their pH, particle size, polydispersity index and zeta potential. The results showed that PPFO contained a high amount of phytonutrients, especially total carotenoid (1497 ppm) and total tocopherol and tocotrienol (2269 ppm) contents. The newly developed nanoemulgels maintained their particles in nano size and showed good stability with high negative zeta potentials. Sample nanoemulgel formulated with 3% PPFO diluted in VCO as effective concentration showed significantly stronger antioxidant activity than the control which was formulated from 3% tocopheryl acetate diluted in mineral oil, towards DPPH and ABTS radicals, with IC 50 values of 67.41 and 44.28 µL/mL, respectively. For the antibacterial activities, the sample nanoemulgel was found to inhibit Gram positive bacteria S. aureus and S. epidermidis growth but not the Gram negative strain E. coli. Overall, this study revealed the potential of SF-extracted PPFO as an active ingredient in the antioxidant topical formulations thus future study on in vitro skin cell models is highly recommended for validation.

Matched MeSH terms: Emulsions/chemistry
Fulltext Phase behaviour and formation of fatty acid esters nanoemulsions containing piroxicam

Mat Hadzir N, Basri M, Abdul Rahman MB, Salleh AB, Raja Abdul Rahman RN, Basri H

AAPS PharmSciTech, 2013 Mar;14(1):456-63.
PMID: 23386307 DOI: 10.1208/s12249-013-9929-1

Fatty acid esters are long-chain esters, produced from the reaction of fatty acids and alcohols. They possess potential applications in cosmetic and pharmaceutical formulations due to their excellent wetting behaviour at interfaces and a non-greasy feeling when applied on the skin surfaces. This preliminary work was carried out to construct pseudo-ternary phase diagrams for oleyl laurate, oleyl stearate and oleyl oleate with surfactants and piroxicam. Then, the preparation and optimization study via 'One-At-A-Time Approach' were carried out to determine the optimum amount of oil, surfactants and stabilizer using low-energy emulsification method. The results revealed that multi-phase region dominated the three pseudo-ternary phase diagrams. A composition was chosen from each multi-phase region for preparing the nanoemulsions systems containing piroxicam by incorporating a hydrocolloid stabilizer. The results showed that the optimum amount (w/w) of oil for oleyl laurate nanoemulsions was 30 and 20 g (w/w) for oleyl stearate nanoemulsions and oleyl oleate nanoemulsions. For each nanoemulsions system, the amount of mixed surfactants and stabilizer needed for the emulsification to take place was found to be 10 and 0.5 g (w/w), respectively. The emulsification process via high-energy emulsification method successfully produced nano-sized range particles. The nanoemulsions systems passed the centrifugation test and freeze-thaw cycle with no phase failures, and stable for 3 months at various storage temperatures (3°C, 25°C and 45°C). The results proved that the prepared nanoemulsions system cannot be formed spontaneously, and thus, energy input was required to produce nano-sized range particles.

Matched MeSH terms: Emulsions*
Fulltext Physicochemical properties and sensory characteristics of sausage formulated with surimi powder

Santana P, Huda N, Yang TA

J Food Sci Technol, 2015 Mar;52(3):1507-15.
PMID: 25745219 DOI: 10.1007/s13197-013-1145-1

The objectives of this study were to determine the physicochemical properties and sensory characteristics of fish sausage made with 100 % threadfin bream (Nemipterus japonicus) surimi powder (SP100), a mix of 50 % surimi powder and 50 % frozen surimi (SP50), and a control (100 % frozen surimi). No significant differences in protein content and folding test results (P > 0.05) were detected among the SP100 and SP50 samples and the control. Gel strength of SP100 was lower (P > 0.05) than that of the control. The texture profile analysis (TPA) values (hardness, cohesiveness, springiness, and chewiness) of SP100 were significantly lower (P

Matched MeSH terms: Emulsions
Self-assembled potential bio nanocarriers for drug delivery

Akter N, Radiman S, Mohamed F, Reza MI

Mini Rev Med Chem, 2013 Jul;13(9):1327-39.
PMID: 23544469

Self-assembled nanocarriers attract increasing attention due to their wide application in various practical fields; among them, one of the most focused fields is drug delivery. Appropriate selection of surfactant is the basis for preparing a successful nanocarrier. Until now, from phospholipid to synthetic surfactants, many surfactants have been used to explore a suitable drug delivery vehicle for the complex in-vivo environment. Among all, bio surfactants are found to be more suitable due to their bio-origin, less-toxicity, biodegradability, cheaper rate and above all, their versatile molecular structures. This molecular property enables them to self assemble into fascinating structures. Moreover, binding DNA, enhancing pH sensitivity and stability allows novelty over their synthetic counterparts and phospholipid. This review paper focuses on the properties and applications of bio-nano-carriers for drug delivery. Micelle, microemulsion, and vesicle are the three nanocarriers which are discussed herein.

Matched MeSH terms: Emulsions
Fulltext Stability Study of Emulsion Liquid Membrane via Emulsion Size and Membrane Breakage on Acetaminophen Removal from Aqueous Solution Using TOA

Zaulkiflee ND, Ahmad AL, Sugumaran J, Lah NFC

ACS Omega, 2020 Sep 22;5(37):23892-23897.
PMID: 32984709 DOI: 10.1021/acsomega.0c03142

The purpose of this study is to explore the emulsion liquid membrane stability for acetaminophen (ACTP) removal from aqueous solution. In this work, the membrane phase was prepared by dissolving trioctylamine (TOA) with kerosene and Span80. The stability of the emulsion in terms of emulsion size, membrane breakage, and its efficiency in removing ACTP was considered for the optimization of parameters. Investigation on the stability of emulsion was carried out by manipulating the concentration of stripping agent, agitation speed, extraction time, and treat ratio. The best condition to produce a very stable emulsion was achieved at 0.1 M of stripping agent concentration, with 300 rpm of agitation speed for 3 min of extraction time with a treat ratio of 3:1. Eighty-five percent of ACTP successfully stripped into the emulsion with minimum membrane breakage of 0.17% through this experiment.

Matched MeSH terms: Emulsions
Formation of Antihyperlipidemic Nano-Ezetimibe from Volatile Microemulsion Template for Enhanced Dissolution Profile

Saleem MA, Yasir Siddique M, Nazar MF, Khan SU, Ahmad A, Khan R, et al.

Langmuir, 2020 07 14;36(27):7908-7915.
PMID: 32551692 DOI: 10.1021/acs.langmuir.0c01016

Nanostructures play an important role in targeting sparingly water-soluble drugs to specific sites. Because of the structural flexibility and stability, the use of template microemulsions (μEs) can produce functional nanopharmaceuticals of different sizes, shapes, and chemical properties. In this article, we report a new volatile oil-in-water (o/w) μE formulation comprising ethyl acetate/ethanol/brij-35/water to obtain the highly water-dispersible nanoparticles of an antihyperlipidemic agent, ezetimibe (EZM-NPs), to enhance its dissolution profile. A pseudoternary phase diagram was delineated in a specified brij-35/ethanol ratio (1:1) to describe the transparent, optically isotropic domain of the as-formulated μE. The water-dilutable μE formulation, comprising an optimum composition of ethyl acetate (18.0%), ethanol (25.0%), brij-35 (25.0%), and water (32.0%), showed a good dissolvability of EZM around 4.8 wt % at pH 5.2. Electron micrographs showed a fine monomodal collection of EZM-loaded μE droplets (∼45 nm) that did not coalesce even after lyophilization, forming small spherical EZM-NPs (∼60 nm). However, the maturity of nanodrug droplets observed through dynamic light scattering suggests the affinity of EZM to the nonpolar microenvironment, which was further supported through peak-to-peak correlation of infrared analysis and fluorescence measurements. Moreover, the release profile of the as-obtained EZM-nanopowder increased significantly >98% in 30 min, which indicates that a reduced drug concentration will be needed for capsules or tablets in the future and can be simply incorporated into the multidosage formulation of EZM.

Matched MeSH terms: Emulsions
Emulsion liquid membrane modeling for chromium removal from electroplating wastewater using TOMAC as a carrier

Othman N, Noah NFM, Sulaiman RNR, Jusoh N, Tan WT

Water Environ Res, 2021 Sep;93(9):1669-1679.
PMID: 33704848 DOI: 10.1002/wer.1551

Hexavalent chromium, emanating primarily from the electroplating industries, can be reduced to the less toxic trivalent variety by several methods, including emulsion liquid membrane (ELM). In this work, studies on the continuous removal of chromium from authentic electroplating wastewater by ELM are reported. The effects of treat ratio, external feed phase, and stripping agent concentration were examined. A mathematical boundary breakage model was used to study the extraction efficiency of chromium through the ELM process. The model representing the prediction of ELM extraction performance for chromium was validated through the comparison between the simulation and experimental results. The result showed the simulation model is found to be in good agreement with the experimental result. Almost 100% of 40 ppm chromium in the external feed phase was extracted within 3 to 5 min using 0.022 M TOMAC as extractant, 1.0 M acidic thiourea in the internal phase, and 1 to 5 of treat ratio. PRACTITIONER POINTS: Hexavalent chromium, emanating primarily from electroplating industries, can be reduced to the less toxic trivalent using ELM process. The developed method was tested for its applicability with predominant species of Cr2 O7 2- in real rinse electroplating wastewater. The extraction efficiency (%) of Cr (VI) was almost 100% for 40 ppm Cr in the external feed phase within 3 to 5 min. The result showed the simulation model is found to be in good agreement with the experimental result.

Matched MeSH terms: Emulsions
Fulltext Emulsifying properties of extracted Okra (Abelmoschus esculentus L.) mucilage of different maturity index and its application in coconut milk emulsion

Noorlaila, A., Siti Aziah, A., Asmeda, R., Norizzah, A.R.

International Food Research Journal, 2015;22(2):782-787.
MyJurnal

The emulsifying properties of extracted okra (Abelmoschus esculentus L.) mucilage at different maturity indices (1, 2 and 3) were studied. The okra mucilage was prepared using water extraction method and was determined their viscosity at different temperature (10, 30, 50 and 70°C), water holding capacity (WHC), oil holding capacity (OHC), as well as their emulsion capacity (EC) and emulsion stability (ES). Results found that okra with maturity index 2 produced the highest percentage yield of mucilage (1.46%) and followed by index 1 (1.10%) and index 3 (0.31%) (p

Matched MeSH terms: Emulsions
In situ quantification of β-carotene partitioning in oil-in-water emulsions by confocal Raman microscopy

Wan Mohamad WAF, Buckow R, Augustin M, McNaughton D

Food Chem, 2017 Oct 15;233:197-203.
PMID: 28530566 DOI: 10.1016/j.foodchem.2017.04.086

Confocal Raman microscopy (CRM) was able to quantify the β-carotene concentration in oil droplets and determine the partitioning characteristics of β-carotene within the emulsion system in situ. The results were validated by a conventional method involving solvent extraction of β-carotene separately from the total emulsion as well as the aqueous phase separated by centrifugation, and quantification by absorption spectrophotometry. CRM also enabled the localization of β-carotene in an emulsion. From the Raman image, the β-carotene partitioning between the aqueous and oil phases of palm olein-in-water emulsions stabilized by whey protein isolate (WPI) was observed. Increasing the concentration of β-carotene in an emulsion (from 0.1 to 0.3g/kg emulsion) with a fixed gross composition (10% palm olein:2% WPI) decreased the concentration of β-carotene in the oil droplet. CRM is a powerful tool for in situ analyses of components in heterogeneous systems such as emulsions.

Matched MeSH terms: Emulsions
Fulltext Characterization and functional properties of gelatin extracted from goatskin

Zilhadia, Yahdiana,H., Effionora, A., Irwandi, J.

International Food Research Journal, 2018;25(1):275-281.
MyJurnal

Gelatin from goatskin pretreated with hydrochloric acid and extracted with distilled water at 60oC for 9 hours was characterized and compared to that of bovine skin gelatin (BSG). A yield of 10.26% (wet weight basis) was obtained. Goatskin gelatin (GSG) had high protein (86.58%), suitable moisture (9.58%), low fat (1.46%) and low ash (0.11%) content. The functional properties of GSG including gel strength (301 g bloom) and emulsion activity index (94.27%) were higher than the functional properties of BSG including gel strength (192 g bloom) and emulsion activity index (49.74%). The foaming property of GSG (102%) was lower than that of BSG (164.67%). This study shows that GSG has a high potential for application as a source of commercial gelatin.

Matched MeSH terms: Emulsions
Fracture toughness and impact strength of hollow epoxy particles-toughened polyester composite

Low L, Abu Bakar A

Sains Malaysiana, 2013;42:443-448.

Hollow epoxy particles (HEP) serving as reinforcing fillers were prepared using the water-based emulsion method in this study. HEP was incorporated into the polyester matrix at various loading, ranging from 0 wt% to 9 wt%, to toughen the brittle polyester thermoset. The polyester composites were prepared using the casting technique. The fracture toughness and impact strength of the polyester composites increased with increasing the HEP loading up to 5 wt%, after which
there was a drop. The improvement in fracture toughness and impact strength is attributed to the good polymer-filler interaction. This finding was further supported by the scanning electron micrograph, in which it was shown that the polyester resin was interlocked into the pore regions of the HEP filler. The reduction in fracture toughness and impact strength of the polyester composite were believed to be attributed to the filler agglomeration. This filler-filler interaction would create stress concentration areas and eventually weakened the interfacial adhesion between the polymer matrix and the filler particles. Hence, lower fracture toughness and impact strength of the highly HEP-filled polyester composites (above 5 wt%) were detected.

Matched MeSH terms: Emulsions
Fulltext Surface-Functionalized Superparamagnetic Nanoparticles (SPNs) for Enhanced Oil Recovery: Effects of Surface Modifiers and Their Architectures

Khalil M, Aulia G, Budianto E, Mohamed Jan B, Habib SH, Amir Z, et al.

ACS Omega, 2019 Dec 17;4(25):21477-21486.
PMID: 31867543 DOI: 10.1021/acsomega.9b03174

Superparamagnetic nanoparticles (SPNs) have been considered as one of the most studied nanomaterials for subsurface applications, including in enhanced oil recovery (EOR), due to their unique physicochemical properties. However, a comprehensive understanding of the effect of surface functionalization on the ability of the nanoparticles to improve secondary and tertiary oil recoveries remains unclear. Therefore, investigations on the application of bare and surface-functionalized SPNs in EOR using a sand pack were carried out in this study. Here, the as-prepared SPNs were functionalized using oleic acid (OA) and polyacrylamide (PAM) to obtain several types of nanostructure architectures such as OA-SPN, core-shell SPN@PAM, and SPN-PAM. Based on the result, it is found that both the viscosity and mobility of the nanofluids were significantly affected by not only the concentration of the nanoparticles but also the type and architecture of the surface modifier, which dictated particle hydrophilicity. According to the sand pack tests, the nanofluid containing SPN-PAM was able to recover as much as 19.28% of additional oil in a relatively low concentration (0.9% w/v). The high oil recovery enhancement was presumably due to the ability of suspended SPN-PAM to act as a mobility control and wettability alteration agent and facilitate the formation of a Pickering emulsion and disjoining pressure.

Matched MeSH terms: Emulsions
Glyceryl ether (mono-tert-butoxypropanediol) in emulsion system

Yusrabbil Amiyati Yusof, Zafarizal Aldrin Azizul Hasan, Azhar Ariffin

Sains Malaysiana, 2018;47:511-515.

This paper reports the effects of glyceryl ether specifically mono-tert-butoxypropanediol on oil in water emulsion system.
Based on 12 HLB value, screening for stable emulsions was carried out without the presence of glyceryl ether. A stable
emulsion was used as a control. Then the effects of glyceryl ether on the emulsion system were investigated. The emulsions
prepared were analyzed for stability, viscosity, pH value, particle size, in vitro dermal irritation potential, in vitro ocular
irritation potential and also moisturizing property. The incorporation of glycerol in the emulsion system was also done
for comparison. Emulsions with glyceryl ether showed lower viscosity values than emulsions with glycerol. Furthermore,
the emulsions also exhibited moisturizing property compared to the control emulsion. Glyceryl ether is suitable to be
used in cosmetic products which require reduced viscosity but retain its skin hydration property.

Matched MeSH terms: Emulsions

Filters

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

External Links