54 research outputs found
The effect of temperature on the dispersion of α-Mangostin in PNIPAM microgel system / Madihah Ahmad, Bohari M. Yamin and Azwan Mat Lazim
No full textα-Mangostin was extracted from the pericarp of the Malaysian local Garcinia mangostana linn., The structure was characterised by Infrared red, UV-Visible and Nuclear
Magnetic Resonance spectroscopic data. The fluorescence peak at 500nm in ethanol was not observed in PNIPAM microgel solution. The increase of colloidal size of the gel in the presence of α-mangostin was studied by Dynamic Light Scattering and Transmission Electron Microscope. The size of the particle also increases with increasing temperature up to 45⁰C after which it began to shrink. The TEM micrograph at 45°C showed a uniformly structured pattern of the gel occurs in the range of the lowest solution critical temperatur
Kebolehserapan metilena biru oleh hidrogel selulosa bakteria teradiasi gamma menggunakan isoterma langmuir dan freundlich
No full textSynthesis and characterization of pH sensitive hydrogel using extracted pectin from dragon fruit peel
No full textThe aim of this study is to synthesis pectin-based hydrogel from the dragon fruit peel. The pectin was extracted using acid extraction (pH 3.5) that carried out at 60 oC for 30 minutes. The extracted compound conformation was analyzed by calculating the degree of esterification (DE) and the analysis was confirmed by the FTIR analysis spectrum. The dragon fruit peel pectin (PcDF) and acrylic acid (AA) hydrogel (AA-PcDF) was fabricated using a free radical polymerization in aqueous solution. Its uptaking efficiency was determined in different pH buffer solutions and their swelling percentage was calculated. Futher characterizations were made by using FTIR and SEM to examine the AA-PcDF hydrogel physicochemical properties. Results obtained showed that this new material has a high potential to be used as biomaterial in pharmaceutical and medical purposes
A study on microgel system as a template for dispersion and separation of chiral tartaric acid
No full textPenentuan kualiti minyak masak dan lemak komersial menggunakan teknik kimometik
No full textDalam kajian ini, kaedah kimometrik telah digunakan bagi menentukan kualiti beberapa jenis minyak masak komersil daripada dua jenama yang berbeza. Sampel minyak masak yang telah digunakan ialah minyak zaitun, minyak bunga matahari dan mentega dalam dua keadaan yang berbeza, iaitu segar dan digoreng. Kaedah konvensional dilakukan untuk menentukan kualiti minyak, iaitu peratus asid lemak bebas, nilai iodin dan nilai peroksida. Sebanyak 12 sampel minyak telah dianalisis menggunakan spektroskopi inframerah fourier transformasi (FTIR) pada jalur 4000-400 cm-1. Stimulasi komputer telah dilakukan berdasarkan pencaman corak FTIR dan data pencaman corak dioptimumkan kepada model analisis komponen utama (PCA) dan kuasa dua terkecil separa (PLS). Model PCA digunakan dalam kajian ini bagi membezakan sifat-sifat antara minyak komersial segar dan minyak digoreng. Kemudian model PLS digunakan untuk mendapatkan ujian pengesahan antara kedua-dua minyak. Ujian ini dapat membandingkan hasil yang diramal oleh kaedah PLS dengan nilai yang diperoleh menggunakan kaedah konvensional. Keputusan yang diperoleh menunjukkan ujian pengesahan bagi minyak komersial mempunyai nilai kecerunan graf iaitu 0.90. Ini menunjukkan kaedah kimometik adalah signifikan dengan kaedah konvensional
Applications of responsive microgels for separation and recovery
No full textEThOS - Electronic Theses Online ServiceGBUnited Kingdo
Authentication of Rusa timorensis DNA Using Sequencing Assay with Modified Extraction Method
No full textA technique to isolate DNA from deer meat was established to authenticate the deer species and was successfully extracted from deer meat. The method was based on the Epicentre MasterPureTM Complete DNA and RNA Purification Kit extraction kit with slight modification by increasing the volume of Proteinase K and RNase from 5 µL to 20 µL each. The recovery of deer DNA was then analysed by Polymerase Chain Reaction using cytochrome b gene oligonucleotide primers for the deer family, which targeted the mitochondrial DNA. The increasing volume of Proteinase K and RNase resulted in clean DNA and no smearing after performing Polymerase Chain Reaction. Furthermore, the amplified DNA product was extended to sequence assay to authenticate deer species above 95% maximum identification. The result showed that the increasing volume of Proteinase K and RNase offered a high yield of DNA recovery, which provided more than 100 ng per μL and was useful in validating animal-based sources, especially in deer products
Stimulus-Responsive Heteroaggregation of Colloidal Dispersions: Reversible Systems and Composite Materials
No full textHeteroaggregation is the aggregation of mixed particle systems where the colloidal particles may differ in charge, size and chemical composition. The phenomenon of heteroaggregation is of great relevance in industrial processes and the natural environment. This review will focus on binary heteroaggregation where at least one of the particles is a stimulus-responsive smart particle. Aggregation under various conditions of pH, temperature, light and relative concentration can be induced by the careful manipulation of any one or more of these environmental conditions during the heteroaggregation of smart particles. Stimulus response provides the potential for reversibility from an aggregated to a stable system and exceptional control over inter-particle interactions. The significant fundamental and applied studies that have made an impact in this area will be discussed
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