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Pembentukan granul berasaskan asid mefenamik dan polietilena glikol (PEG) menggunakan teknik pengranulan tekanan terayun dalam turus terbendalir
The Malaysian Journal of Analytical Sciences Pub Date : 2018-04-01 DOI: 10.17576/MJAS-2018-2202-18
Ab Ghani Salinda, Noor Fitrah Abu Bakar, M. R. A. Bakar, Y. Yusof, Norazah Abd Rahman
{"title":"Pembentukan granul berasaskan asid mefenamik dan polietilena glikol (PEG) menggunakan teknik pengranulan tekanan terayun dalam turus terbendalir","authors":"Ab Ghani Salinda, Noor Fitrah Abu Bakar, M. R. A. Bakar, Y. Yusof, Norazah Abd Rahman","doi":"10.17576/MJAS-2018-2202-18","DOIUrl":"https://doi.org/10.17576/MJAS-2018-2202-18","url":null,"abstract":"Granulation of mefenamic acid particles was conducted to produce spherical shape, narrow size distribution of granules, high granule strength and good content uniformity by using Pressure Swing Granulation (PSG) technique in a fluidized bed. Two types (binderless and with binder) of granules namely lactose-mefenamic acid (MA) and lactose-polyethylene glycol (PEG)-(MA) with mass ratio of 30:70 and 25:5:70 were produced respectively. The later type of granules was heated for 80 ˚C, above the PEG melting point. Results indicated that all granules were uniform, spherical and narrow size distribution with the average granules size was less than 500 μm. The tensile strength of the lactose-PEG-MA was higher than the lactose-MA due to heating process. The tensile strength of lactose-PEG-MA and lactose-MA with average granules size of 500 μm were 0.42 MPa and 0.33 MPa, respectively. The drug contents in both types of granules were uniform i.e. around 70 ± 0.3 wt.%.","PeriodicalId":22844,"journal":{"name":"The Malaysian Journal of Analytical Sciences","volume":"52 1","pages":"318-325"},"PeriodicalIF":0.0,"publicationDate":"2018-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88357538","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Diterpenoid-diterpenoid terbaharu daripada akar Croton hirtus (Euphorbiaceae)
The Malaysian Journal of Analytical Sciences Pub Date : 2018-02-01 DOI: 10.17576/MJAS-2018-2201-08
A. R. Rosandy, Anis Asmi Azman, R. Khalid, Rizafizah Othaman, Mohamad Azwani Shah Mat Lazim, Iqbal M. Choudary, Yana M. Syah, Jalifah Latip, Ikram M. Said, Muntaz Abu Bakar
{"title":"Diterpenoid-diterpenoid terbaharu daripada akar Croton hirtus (Euphorbiaceae)","authors":"A. R. Rosandy, Anis Asmi Azman, R. Khalid, Rizafizah Othaman, Mohamad Azwani Shah Mat Lazim, Iqbal M. Choudary, Yana M. Syah, Jalifah Latip, Ikram M. Said, Muntaz Abu Bakar","doi":"10.17576/MJAS-2018-2201-08","DOIUrl":"https://doi.org/10.17576/MJAS-2018-2201-08","url":null,"abstract":"The root of Croton hirtus was collected at Tanjung Sepat, Banting for study of its chemical compounds. This sample was dried before being ground and extracted using the methanol solvent at room temperature for three days yielding 18.25 gram of crude extract. The crude extracts obtained were analysed using thin layer chromatography (TLC) then fractionated via vacuum column chromatography (VLC) and proceed the isolation using radial chromatography (RC) to get the pure compounds. The pure compounds obtained were elucidated by nuclear magnetic resonance (NMR), Fourier Transform Infrared (FT-IR) and mass spectroscopy to confirm their structures and from that analysis, the compounds were identified as two new compounds naming (-)-5,8-dihydroxyjatrophan-3-one (1) and (+)-14,16,17-trihydroxykauran-1-on (2) with total weight 4.9 mg and 4.5 mg respectively. This two compound were reported for this time on this genus.","PeriodicalId":22844,"journal":{"name":"The Malaysian Journal of Analytical Sciences","volume":"6 1","pages":"64-71"},"PeriodicalIF":0.0,"publicationDate":"2018-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88565921","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Kesan kaedah pengekstrakan fukoidan terhadap hasil, kandungan fukosa dan ketulenan fukoidan daripada Sargassum sp. Dari pulau langkawi, Malaysia
The Malaysian Journal of Analytical Sciences Pub Date : 2018-02-01 DOI: 10.17576/MJAS-2018-2201-11
Bibi Marliana Baba, Wan Mustapha, Seng Joe Lim
{"title":"Kesan kaedah pengekstrakan fukoidan terhadap hasil, kandungan fukosa dan ketulenan fukoidan daripada Sargassum sp. Dari pulau langkawi, Malaysia","authors":"Bibi Marliana Baba, Wan Mustapha, Seng Joe Lim","doi":"10.17576/MJAS-2018-2201-11","DOIUrl":"https://doi.org/10.17576/MJAS-2018-2201-11","url":null,"abstract":"The objective of this study was to determine the effect of extraction methods on the yield, fucose content and purity of fucoidan that had been isolated from brown seaweed, Sargassum sp. The extraction of fucoidan was carried out based on the factorial design assigned, which involved three different parameters including two types of extraction (acid and alkaline), three different extraction temperatures (45, 65 and 85 °C) and three different extraction time (1, 3 and 5 hours). Results obtained showed that the best extraction parameter that gave the highest yield of fucoidan extract was the alkaline extraction at 65 °C for 3 hours. Alkaline extraction also produced higher purity and better quality of fucoidan compared to the fucoidan extracted by hydrochloric acidic.","PeriodicalId":22844,"journal":{"name":"The Malaysian Journal of Analytical Sciences","volume":"88 1","pages":"87-94"},"PeriodicalIF":0.0,"publicationDate":"2018-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78346027","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 3
Pengkompleksan 5,5,7,12,12,14-heksametil-1,4,8,11-tetraazasiklo tetraazadeka-7,14-dienium diperklorat dengan kuprum(II) asetat monohidrat dalam cecair ionik
The Malaysian Journal of Analytical Sciences Pub Date : 2018-02-01 DOI: 10.17576/MJAS-2018-2201-04
N. M. Ali, N. Zaid, Nurul Huda Abd Karim, B. M. Yamin, Nur Hasyareeda Hassan
{"title":"Pengkompleksan 5,5,7,12,12,14-heksametil-1,4,8,11-tetraazasiklo tetraazadeka-7,14-dienium diperklorat dengan kuprum(II) asetat monohidrat dalam cecair ionik","authors":"N. M. Ali, N. Zaid, Nurul Huda Abd Karim, B. M. Yamin, Nur Hasyareeda Hassan","doi":"10.17576/MJAS-2018-2201-04","DOIUrl":"https://doi.org/10.17576/MJAS-2018-2201-04","url":null,"abstract":"In the previous study, 5,5,7,12,12,14–hexamethyl–1,4,8,11–tetraazacyclotetradeca–7,14–dienium diperchlorate, [Me6C10H16N4](ClO4)2 formed complex of C16H34N4OCu(ClO4)2 and C16H32N4Cu(ClO4)2 when reacted with copper(II) acetate monohydrate in acetonitrile and aqueous solutions, respectively. However, when the same reaction carried out in 1–butyl–3– methylimidazolium hexafluorophosphate ionic liquid, [Bmim][PF6], disproportionation took place to give bis(ethylenediamine) bis(perchlorato-O) copper(II) complex, C4H16N4Cu(ClO4)2. X-ray study showed that the central copper atom was coordinated to two ethylenediamine ligands and two oxygen atoms of perchlorate ions in a distorted octahedral environment. Thermogravimetric Analysis (TGA) study showed the complex decomposition in one spontaneous mass loss at 260 oC due to the explosive nature of the perchlorate.","PeriodicalId":22844,"journal":{"name":"The Malaysian Journal of Analytical Sciences","volume":"4 1","pages":"27-34"},"PeriodicalIF":0.0,"publicationDate":"2018-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75978682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Ko-pemekaan pemeka semulajadi disari daripada kayu rengas (Gluta spp.) dan mengkulang (Heritiera elata) dengan pewarna rutenium (N719) untuk meningkatkan prestasi sel solar terpeka pewarna
The Malaysian Journal of Analytical Sciences Pub Date : 2018-02-01 DOI: 10.17576/MJAS-2018-2201-12
N. Safie, Norasikin Ahmad Ludin, Norul Hisham Hamid, Mohd Sukor Su'ait, Mohd Asri Mat Teridi, Suhaila Sepeai, Mohd Adib Ibrahim, K. Sopian, Hironori Arakawa
{"title":"Ko-pemekaan pemeka semulajadi disari daripada kayu rengas (Gluta spp.) dan mengkulang (Heritiera elata) dengan pewarna rutenium (N719) untuk meningkatkan prestasi sel solar terpeka pewarna","authors":"N. Safie, Norasikin Ahmad Ludin, Norul Hisham Hamid, Mohd Sukor Su'ait, Mohd Asri Mat Teridi, Suhaila Sepeai, Mohd Adib Ibrahim, K. Sopian, Hironori Arakawa","doi":"10.17576/MJAS-2018-2201-12","DOIUrl":"https://doi.org/10.17576/MJAS-2018-2201-12","url":null,"abstract":"In this study, photovoltaic performance was improved when two natural sensitizers, namely, rengas ( Gluta spp. ) and mengkulang ( Heritiera elata ), were mixed with ruthenium (N719) sensitizer. Five different ratios were prepared and their performances were compared with individual sensitizers. The components of the sensitizers were analyzed via ultraviolet–visible spectrophotometry and Fourier transform infrared spectroscopy. The band gap values and the highest occupied molecular orbital–lowest unoccupied molecular orbital (HOMO-LUMO) levels were calculated using data obtained from photoluminescence analysis and cyclic voltammetry. The mengkulang: N719 (80%:20%) sensitizer exhibits the highest conversion efficiency ( ŋ ), which is 0.58% with an open circuit voltage ( V oc ) of 0.63 V, a short circuit photocurrent density ( J sc ) of 2.1 mA/cm 2 , and a fill factor ( ff ) of 0.44. By contrast, the individual mengkulang sensitizer presents a poor conversion efficiency ( ŋ ) of 0.16%.","PeriodicalId":22844,"journal":{"name":"The Malaysian Journal of Analytical Sciences","volume":"134 1","pages":"95-106"},"PeriodicalIF":0.0,"publicationDate":"2018-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76283527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Photocatalytic degradation of methylene blue with silver doped ZnO nanoparticles grown on microscopic sand particles. 纳米银掺杂ZnO光催化降解亚甲基蓝的研究
The Malaysian Journal of Analytical Sciences Pub Date : 2018-01-01 DOI: 10.17576/mjas-2018-2202-12
M. S. Azmina, R. Nor, H. A. Rafaie, A. Fairus, Z. Osman
{"title":"Photocatalytic degradation of methylene blue with silver doped ZnO nanoparticles grown on microscopic sand particles.","authors":"M. S. Azmina, R. Nor, H. A. Rafaie, A. Fairus, Z. Osman","doi":"10.17576/mjas-2018-2202-12","DOIUrl":"https://doi.org/10.17576/mjas-2018-2202-12","url":null,"abstract":"Pure and Ag doped ZnO nanoparticles were synthesized on microscopic sand particles by sol-gel method. Silver nitrate was used as the doping precursor, Ag doping levels of 1.3 to 7.7 of Ag/Zn ratios were obtained based on energy dispersive X-ray spectroscopy analysis. X-ray diffraction results show that a ZnO (101) peak of Ag doped samples are shifted towards lower degree which around 0.17 compared to pure ZnO NPs, indicating the existence of doping in the Ag doped samples. The pure and Ag doped ZnO samples were used as photocatalysts in the degradation of methylene blue under UV irradiation. Photodegradation efficiency based on the pseudo-first kinetics model gave measured values of the photodegradation rate, k of 8.9, 11.8, 12.7, 14.8 and 17.4 x 10 min for pure, 1.3, 1.6, 1.7 and 2.4 of Ag/Zn ratios, respectively. At higher doping levels of 3.3 and 7.7 of Ag/Zn ratios, the k values receded to 12.7 and 12.0 x 10 min, respectively. The increasing trend on k values can be due to the doping defect levels which trapped the recombining electrons, thus lengthening the lifetime of the electron hole pairs.","PeriodicalId":22844,"journal":{"name":"The Malaysian Journal of Analytical Sciences","volume":"49 1","pages":"270-278"},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83659309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 6
Elektrod komposit logam berasaskan arang bagi rawatan air buangan
The Malaysian Journal of Analytical Sciences Pub Date : 2017-12-01 DOI: 10.17576/MJAS-2017-2106-26
Majd Ahmed Jumaah, M. Othman, Muhammad Rahimi Usop, Jumat Salimon, Baydaa Khalaf, Wan Mohd Afiq Wan Mohd Khalik
{"title":"Elektrod komposit logam berasaskan arang bagi rawatan air buangan","authors":"Majd Ahmed Jumaah, M. Othman, Muhammad Rahimi Usop, Jumat Salimon, Baydaa Khalaf, Wan Mohd Afiq Wan Mohd Khalik","doi":"10.17576/MJAS-2017-2106-26","DOIUrl":"https://doi.org/10.17576/MJAS-2017-2106-26","url":null,"abstract":"","PeriodicalId":22844,"journal":{"name":"The Malaysian Journal of Analytical Sciences","volume":"8 1","pages":"1432-1437"},"PeriodicalIF":0.0,"publicationDate":"2017-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85437719","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Sintesis Mno2 nanobunga poros menggunakan templat silika-APTES
The Malaysian Journal of Analytical Sciences Pub Date : 2017-12-01 DOI: 10.17576/MJAS-2017-2106-09
Siti Zubaidah Hasan, M. Othman, Muhammad Rahimi Usop
{"title":"Sintesis Mno2 nanobunga poros menggunakan templat silika-APTES","authors":"Siti Zubaidah Hasan, M. Othman, Muhammad Rahimi Usop","doi":"10.17576/MJAS-2017-2106-09","DOIUrl":"https://doi.org/10.17576/MJAS-2017-2106-09","url":null,"abstract":"","PeriodicalId":22844,"journal":{"name":"The Malaysian Journal of Analytical Sciences","volume":"14 1","pages":"1276-1288"},"PeriodicalIF":0.0,"publicationDate":"2017-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82915684","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Nanoemulsi berasaskan olein sawit sebagai pembawa vitamin E
The Malaysian Journal of Analytical Sciences Pub Date : 2017-12-01 DOI: 10.17576/MJAS-2017-2106-22
Suria Ramli, Norhakimah Norhman, Norhidayu Zainuddin, Safiah Mohamad Ja’afar, I. A. Rahman
{"title":"Nanoemulsi berasaskan olein sawit sebagai pembawa vitamin E","authors":"Suria Ramli, Norhakimah Norhman, Norhidayu Zainuddin, Safiah Mohamad Ja’afar, I. A. Rahman","doi":"10.17576/MJAS-2017-2106-22","DOIUrl":"https://doi.org/10.17576/MJAS-2017-2106-22","url":null,"abstract":"Aging process makes our skin getting thinner and drier. Antioxidant based on nanoemulsion system is favourable because of its effectiveness. This study was conducted to develop nanoemulsion system based on palm olein as a carrier of vitamin E and the physicochemical behaviours of the system were studied. Palm olein as oil phase, polyoxyethylene (4) lauryl ether (Brij 30) was used as a surfactant and vitamin E as an anti-aging agent. The mixtures of Brij 30 and palm olein at certain ratios were thoroughly mixed and titrated with 5 – 95% wt. of water and homogenized by using homogenizer. The Palm olein/Brij 30/Water mixtures that produced a clear solution and no birefringence after observation under polarized light microscopy are labelled as nanoemulsion. Nanoemulsion region was shown in ternary phase diagram. Based on the ternary diagram, these systems were formed at oil: surfactant (O/S) ratio 4:6, 5:5 and 6:4 and 20 – 50% wt of water. These systems were then characterized for stability test, particle size, electrical conductivity, viscosity and pH. Stability test was done at three temperatures, which were 4, 25 and 40 °C for one month and four cycles of freeze-thaw at storage temperature for 12 hours at each temperature. The systems were stable and no phase separation was observed. Particle size analysis showed that most systems have a particle size within the range of nanoemulsion (20 – 500 nm). Electrical conductivity tests showed that water-in-oil system formed at low water percentage (20 – 30% wt. of water) and bicontinuous at a higher percentage (30 – 50% wt. of water). Viscosity of both systems vitamin E-loaded and unloaded is very low. All systems have a pH value in a range of 6 – 7, which are suitable to be applied to human skin. Based on the physical characteristics of the system, it shows high potential as a vitamin E carrier.","PeriodicalId":22844,"journal":{"name":"The Malaysian Journal of Analytical Sciences","volume":"26 1","pages":"1399-1408"},"PeriodicalIF":0.0,"publicationDate":"2017-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84813369","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 3
Diketopiperazin dihasilkan oleh yis psikropilik Glaciozyma antarctica PI12
The Malaysian Journal of Analytical Sciences Pub Date : 2017-12-01 DOI: 10.17576/MJAS-2017-2106-05
Andi Rifki Rosandy, Muntaz Abu Bakar, Nur Farhana Abdul Rahman, A. Murad, Azira Muhamad, R. Khalid
{"title":"Diketopiperazin dihasilkan oleh yis psikropilik Glaciozyma antarctica PI12","authors":"Andi Rifki Rosandy, Muntaz Abu Bakar, Nur Farhana Abdul Rahman, A. Murad, Azira Muhamad, R. Khalid","doi":"10.17576/MJAS-2017-2106-05","DOIUrl":"https://doi.org/10.17576/MJAS-2017-2106-05","url":null,"abstract":"Four diketopiperazine derivatives; cyclo(-Pro-Val) (1), (-)-cyclo(-Pro-Tyr) (2), (-)-cyclo(-Pro-Phe) (3) and (+)-cyclo(-Pro-Leu) (4) were isolated from the ethyl acetate extract of Glaciozyma antarctica PI12, a cold-adapted yeast that belongs to family Kriegeriales. The compounds were isolated by radial chromatography and thin layer chromatography techniques and the chemical structures were elucidated by infrared (IR), ultraviolet (UV), nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry.","PeriodicalId":22844,"journal":{"name":"The Malaysian Journal of Analytical Sciences","volume":"124 1","pages":"1243-1249"},"PeriodicalIF":0.0,"publicationDate":"2017-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79791111","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
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