Displaying publications 1 - 20 of 1029 in total

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  1. de Toledo TA, da Costa RC, Al-Maqtari HM, Jamalis J, Pizani PS
    PMID: 28259100 DOI: 10.1016/j.saa.2017.02.051
    The heterocyclic chalcone containing thiophene ring 1-(4-chlorophenyl)-3-(2-thienyl)prop-2-en-1-one, C13H9ClOS was synthesized and investigated using experimental techniques such as nuclear magnetic resonance (1H and 13C NMR), Fourier transform infrared spectroscopy (FTIR) at room temperature, differential scanning calorimeter (DSC) from room temperature to 500K and Raman scattering at the temperature range 10-413K in order to study its structure and vibrational properties as well as stability and possible phase transition. Density functional theory (DFT) calculations were performed to determine the vibrational spectrum viewing to improve the knowledge of the material properties. A reasonable agreement was observed between theoretical and experimental Raman spectrum taken at 10K since anharmonic effects of the molecular motion is reduced at low temperatures, leading to a more comprehensive assignment of the vibrational modes. Increasing the temperature up to 393K, was observed the typical phonon anharmonicity behavior associated to changes in the Raman line intensities, line-widths and red-shift, in special in the external mode region, whereas the internal modes region remains almost unchanged due its strong chemical bonds. Furthermore, C13H9ClOS goes to melting phase transition in the temperature range 393-403K and then sublimates in the temperature range 403-413K. This is denounced by the disappearance of the external modes and the absence of internal modes in the Raman spectra, in accordance with DSC curve. The enthalpy (ΔH) obtained from the integration of the endothermic peak in DSC curve centered at 397K is founded to be 121.5J/g.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  2. bin Hussein MZ, Zainal Z, Yahaya AH, Foo DW
    J Control Release, 2002 Aug 21;82(2-3):417-27.
    PMID: 12175754
    Formation of the so-called organic-inorganic nanohybrid material was exploited for the preparation of a controlled release formulation. The inorganic Zn-Al-layered double hydroxide (LDH) was used as a matrix, hosting an active agent or a guest, alpha-naphthaleneacetate (NAA), a plant growth regulator by self-assembly technique. The reverse process, i.e., the deintercalation or release of the guest, NAA was found to be rapid initially, followed by a more sustained release thereafter and this behavior was dependent on the pH of the release medium, the aqueous solution. The mechanism of release has been interpreted on the basis of the ion-exchange process between the NAA anion intercalated in the lamella host and nitrate or hydroxyl anions in the aqueous solution.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  3. Zwain HM, Chang SM, Dahlan I
    Prep Biochem Biotechnol, 2019;49(4):344-351.
    PMID: 30712465 DOI: 10.1080/10826068.2019.1566144
    Microbial content formed in bioreactors plays a significant role in the anaerobic process. Therefore, the physicochemical characteristics of microbial content in a modified anaerobic inclining-baffled reactor (MAI-BR) treating recycled paper mill effluent (RPME) were investigated using Fourier transform infrared (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), thermogravimetric (TG), and derivative thermogravimetric (DTG) analyses, scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), Brunauer-Emmett-Teller (BET), and surface area analyzer. FTIR spectra revealed that the microbial content had stronger characteristic peaks corresponding to alcohols, water, lipids carbohydrates, proteins, and mineral compounds. Calcite, muscovite, and lepidolite were the prevalent mineral phases found by XRD analysis. The elemental of these minerals like C, Ca, N, O, and Si was confirmed by XPS results. The microbial content samples from each compartment showed similar thermal behavior. SEM images showed that straight rod-shaped and Methanosaeta-like microorganisms were predominant, whereas C, O, and Ca were noticed by EDS on the surface of granules. The BET surface areas and pores of granules are found to decline throughout the reactor's compartment, where Compartment 1 had the largest values. Thus, the findings of this study establish further understanding of the physicochemical properties of microbial content formed in MAI-BR during the RPME treatment.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  4. Zuraida, A., Yusliza, Y., Anuar, H., Mohd Khairul Muhaimin, R.
    MyJurnal
    Starch is a biodegradable polymer produced in abundance from many renewable resources. This study examined the influence of citric acid (0-40% w/wt%) ) and water (0-40% w/wt%) as secondary additive and glycerol as plasticizer on the mechanical properties of bio-plastic starch (BPS) from Malaysian sago. The CA content varies from 0 to 40 w/wt% while water was also varied from 0 to 40 w/wt%. FT-IR spectroscopy showed that acid citric improve the properties of BPS and water give negative effects to the carbon hydrogenbond. It is obvious that the addition of the CA at 30 wt/wt% improve the mechanical property of BPS to more than 40% compare to the addition of water.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  5. Zulkifli FH, Hussain FSJ, Rasad MSBA, Mohd Yusoff M
    Carbohydr Polym, 2014 Dec 19;114:238-245.
    PMID: 25263887 DOI: 10.1016/j.carbpol.2014.08.019
    In this study, a novel fibrous membrane of hydroxyethyl cellulose (HEC)/poly(vinyl alcohol) blend was successfully fabricated by electrospinning technique and characterized. The concentration of HEC (5%) with PVA (15%) was optimized, blended in different ratios (30-50%) and electrospun to get smooth nanofibers. Nanofibrous membranes were made water insoluble by chemically cross-linking by glutaraldehyde and used as scaffolds for the skin tissue engineering. The microstructure, morphology, mechanical and thermal properties of the blended HEC/PVA nanofibrous scaffolds were characterized by scanning electron microscope, Fourier transform infrared spectroscopy, differential scanning colorimetry, universal testing machine and thermogravimetric analysis. Cytotoxicity studies on these nanofibrous scaffolds were carried out using human melanoma cells by the MTT assays. The cells were able to attach and spread in the nanofibrous scaffolds as shown by the SEM images. These preliminary results show that these nanofibrous scaffolds that supports cell adhesion and proliferation is promising for skin tissue engineering.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  6. Zulkefli NN, Masdar MS, Wan Isahak WNR, Md Jahim J, Md Rejab SA, Chien Lye C
    PLoS One, 2019;14(2):e0211713.
    PMID: 30753209 DOI: 10.1371/journal.pone.0211713
    Adsorption technology has led to the development of promising techniques to purify biogas, i.e., biomethane or biohydrogen. Such techniques mainly depend on the adsorbent ability and operating parameters. This research focused on adsorption technology for upgrading biogas technique by developing a novel adsorbent. The commercial coconut shell activated carbon (CAC) and two types of gases (H2S/N2 and H2S/N2/CO2) were used. CAC was modified by copper sulfate (CuSO4), zinc acetate (ZnAc2), potassium hydroxide (KOH), potassium iodide (KI), and sodium carbonate (Na2CO3) on their surface to increase the selectivity of H2S removal. Commercial H2S adsorbents were soaked in 7 wt.% of impregnated solution for 30 min before drying at 120°C for 24 h. The synthesized adsorbent's physical and chemical properties, including surface morphology, porosity, and structures, were characterized by SEM-EDX, FTIR, XRD, TGA, and BET analyses. For real applications, the modified adsorbents were used in a real-time 0.85 L single-column adsorber unit. The operating parameters for the H2S adsorption in the adsorber unit varied in L/D ratio (0.5-2.5) and feed flow rate (1.5-5.5 L/min) where, also equivalent with a gas hourly space velocity, GHSV (212.4-780.0 hour-1) used. The performances of H2S adsorption were then compared with those of the best adsorbent that can be used for further investigation. Characterization results revealed that the impregnated solution homogeneously covered the adsorbent surface, morphology, and properties (i.e., crystallinity and surface area). BET analysis further shows that the modified adsorbents surface area decreased by up to 96%. Hence, ZnAc2-CAC clarify as the best adsorption capacity ranging within 1.3-1.7 mg H2S/g, whereby the studied extended to adsorption-desorption cycle.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  7. Zin, M.H., Abdan, K., Norizan, M.N., Mazlan, N.
    MyJurnal
    The main focus of this study was to obtain the optimum alkaline treatment for banana fibre and the its effect on the mechanical and chemical properties of banana fibre, its surface topography, its heat resistivity, as well as its interfacial bonding with epoxy matrix. Banana fibre was treated with sodium hydroxide (NaOH) under various treatment conditions. The treated fibres were characterised using FTIR spectroscopy. The morphology of a single fibre observed under a Digital Image Analyser indicated slight reduction in fibre diameter with increasing NaOH concentration. The Scanning Electron Microscope (SEM) results showed the deteriorating effect of alkali, which can be seen from the removal of impurities and increment in surface roughness. The mechanical analysis indicates that 6% NaOH treatment with a two-hour immersion time gave the highest tensile strength. The adhesion between single fibre and epoxy resin was analysed through the micro-droplet test. It was found that 6% NaOH treatment with a two-hour immersion yielded the highest interfacial shear stress of 3.96 MPa. The TGA analysis implies that alkaline treatment improved the thermal and heat resistivity of the fibre.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  8. Zhao Y, Han F, Guo L, Zhang J, Zhang H, Abdelaziz IIM, et al.
    Waste Manag, 2021 Dec;136:184-194.
    PMID: 34689097 DOI: 10.1016/j.wasman.2021.10.018
    Postconsumer polyethylene terephthalate (PET) has potential applications in many areas of manufacturing, but contamination by hazardous polyvinyl chloride (PVC) in common waste streams can reduce its recyclable value. Separating collected PET-PVC mixtures before recycling remains very challenging because of the similar physicochemical properties of PET and PVC. Herein, we describe a novel flotation process with corona modification pretreatment to facilitate the separation of PET-PVC mixtures. Through water contact angle, surface free energy, X-ray photoelectron and FT-IR characterization, we found that polar hydroxyl groups can be more easily introduced on the PVC surface than on the PET surface induced by corona modification. This selective wetting can suppress the floatability of PVC, leading to the separation of PET as floating product. A reliable mechanism including two different hydrogen-abstraction pathways was established. Response surface methodology consisting of Plackett-Burman and Box-Behnken designs was adopted for optimization of the combined process, and control parameters were solved based on high-quality prediction models, with fitting from significant variables and interactions. For physical or chemical circulation strategies with PET purity prioritization, the validated purity of the product reached 96.05% at a 626 W corona power, 5.42 m/min passing speed, 24.78 mg/L frother concentration and 286 L/h air flow rate. For the energy recuperation strategy with PET recovery prioritization, the factual recovery reached 98.08% under a 601 W corona power, 6.04 m/min passing speed, 27.55 mg/L frother concentration and 184 L/h air flow rate. The current work provides technological insights into the cleaner disposal of waste plastics.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  9. Zhang Y, Zhou L, Zhang C, Show PL, Du A, Fu J, et al.
    Carbohydr Polym, 2020 Nov 01;247:116670.
    PMID: 32829798 DOI: 10.1016/j.carbpol.2020.116670
    With the growing interest in food safety and in environmental protection, it is more attractive to develop novel biodegradable packaging films. In this regard, one new blending film was prepared with curdlan (CD)/polyvinyl alcohol (PVA)/thyme essential oil. Our results demonstrated that the mechanical properties of the blending film were the best when the ratio of the CD and PVA was 4:1. Further, the barrier properties of the film were optimized by incorporating with thyme essential oil. It was proved that not only water vapor permeability was lower, but also the elongation at break was improved, when 2% (w/w) thyme essential oil used. The potential interactions of the film matrix were analyzed by FTIR, XRD and Cryo-scanning electron microscopy. Importantly, both the antioxidant activity and antibacterial activity were improved. Finally, the blending film was employed for the preservation of chilled meat, while the shelf life was extended up to 10 days.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  10. Zhang W, Chen X, Liu G, Jin G, Li Y, Li G, et al.
    PMID: 34619507 DOI: 10.1016/j.saa.2021.120443
    The popularmedicinal mushroomGanodermalucidum was often cultivated by the natural-log. Generally the short log after cultivation were discarded and became pollutant. Rapid and less destructive method of analysis technical by Fourier Transform Infrared (FTIR) and Two-dimension Infrared (2DIR) correlation spectroscopy were selected to determine the composition changes of the logs after G.lucidum cultivation after first year to fifth year. The FTIR accumulated spectra formed without processed baseline showed the samples relied upon a sequenced increase of higher level than spectrum control Q (Q = Quercus acuttisima) from L + Q-5 (L = Lingzhi), L + Q-3, L + Q-1 to L + Q-2. The spectrum L + Q-4 has the optimum highest peak at box B, C and E from this lumped spectral view. The split spectra pinpointed on the fingerprint region of a sample begins from peak 1737 cm-1. ascribed C = O stretching vibration on acetyl and carboxyl hemicellulose group bonding gradually faded from L + Q-1 to L + Q-4 but appeared again on L + Q-5, possibly due to the degradation of hemicellulose. The absorption of peak around 1626 cm-1,1318 cm-1 and 781 cm-1 could be the characteristic absorption peak of calcium oxalate monohydrate. The correlation table indicated, most of the original structure of the building block of the wooden part was deteriorated and marked the lowest correlation value of the 4th year sample with control Q. The sudden changing pattern of 2nd derivative spectrum L + Q-3 to more flatten pattern spectrum L + Q-4 ascribed the changing contents of cellulose and hemicellulose included the lignin within one year during the G. lucidum cultivation. The 2DIR spectrum of the raw material sample precisely showed that the active site with red color was clustered with the area around 1800-1700 cm-1, 1450-800 cm-1 and 750-400 cm-1. In between, the range 1450-800 cm-1 was the most active cluster. Each of the sample showed the different sequence of autopeak comparison. This study has examined the impact of G. lucidum on the degradation of Q. acuttisima in term of their ecosystem life chain. The components of healthy Q. acuttisima wood including lignin, cellulose, hemicellulose and calcium oxalate monohydrate underwent changes after different years of G. lucidum cultivation.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  11. Zhang P, Wang P, Yan L, Liu L
    Int J Nanomedicine, 2018;13:7047-7059.
    PMID: 30464458 DOI: 10.2147/IJN.S180138
    BACKGROUND: Nasopharyngeal cancer (NPC) is one of the subtypes of head and neck cancers. It occurs rarely, and its prevalence depends mainly on geographical location. Modern-day research is focused on coupling nanotechnology and traditional medicine for combating cancers. Gold nanoparticles (AuNPs) were synthesized from Solanum xanthocarpum (Sx) leaf extract using reduction method.

    METHODS: Characterization of the synthesized AuNPs was done by different techniques such as ultraviolet-visible spectrum absorption, X-ray diffraction, dynamic light scattering, Fourier transform infrared spectroscopy, transmission electron microscopy, and energy-dispersive X-ray analysis.

    RESULTS: All the results showed the successful green synthesis of AuNPs from Sx, which induced apoptosis of C666-1 cell line (NPC cell line). There was a decline in both cell viability and colony formation in C666-1 cells upon treatment with Sx-AuNPs. The cell death was proved to be caused by autophagy and mitochondrial-dependent apoptotic pathway.

    CONCLUSION: Thus, due to their anticancer potential, these nanoparticles coupled with Sx can be used for in vivo applications and clinical research in future.

    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  12. Zetty Shafiqa Othman, Nurul Huda Abd Karim, Saiful Irwan Zubairi, Nur Hasyareeda Hassan, Mamoru Koketsu
    Sains Malaysiana, 2018;47:1473-1482.
    [BMIM]OTf and alcohol-based DES combination with a selected organic solvent (acetone and acetonitrile) have
    been proven to efficiently extracting rotenone (isoflavonoid biopesticide) compound compared to individual organic
    solvents. Their efficiency builds up interest to study the solvent-solute interaction that occurs between both selected
    solvent systems with rotenone. The interaction study was analyzed using FTIR, 1D-NMR and 2D- NMR (NOESY, HMBC).
    Correlation portrayed by NOESY and HMBC of [BMIM]OTf - standard rotenone mixture predicted probable hydrogen
    bonding between the oxygen of rotenone with acidic proton C2-H of [BMIM]OTf. While for the alcohol-based DESrotenone
    mixture, the correlation shows probable interaction to occur between methyl and methoxy group rotenone
    with the hydroxyl group of 1,4-butanediol. In conclusion, potential hydrogen bonding that occurs between solvent
    and solute aid towards the solvent efficiency in extracting rotenone compound while emphasizing on the low cost and
    green mediated solvent systems.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  13. Zeimaran E, Kadir MR, Nor HM, Kamarul T, Djordjevic I
    Bioorg Med Chem Lett, 2013 Dec 15;23(24):6616-9.
    PMID: 24215893 DOI: 10.1016/j.bmcl.2013.10.053
    In this study aliphatic polyacids were synthesized using palm acid oil (PAO) and sunflower oil (SFO) via addition reaction technique. The synthesized materials were characterized using Fourier-transform infra-red (FTIR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-ToF-MS) and thermo-gravimetric analysis (TGA). Mixing formic acid and hydrogen peroxide with PAO or SFO at the ratio 3:10:1 produced the lowest iodine value of 10.57 and 9.24 respectively, indicating the increase in epoxidization of both oils. Adding adipic acid to the epoxidized oils at a ratio of 1:10 increases the acid values of SFO and PAO to 11.22 and 6.73 respectively. The existence of multi-acid groups present in synthesized polyacid was confirmed by MALD-ToF-MS. This feature indicates a possible value to the biomaterials development.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  14. Zeeshan F, Tabbassum M, Kesharwani P
    Protein J, 2019 10;38(5):551-564.
    PMID: 31054037 DOI: 10.1007/s10930-019-09837-4
    Protein drugs are important therapeutic agents however; they may degrade during formulation processing. The objective of this study was to investigate the correlation between secondary structure alterations and the retentions of biological activity of protein upon the application of thermal stress. Catalase, horseradish peroxidase and α- chymotrypsin were employed as model proteins. Each protein was heated in a solid and solution state at a temperature of 70 °C for 1 h. Attenuated total reflectance Fourier transform infrared spectroscopy, size-exclusion chromatography and biological activity assay were performed. Results showed that heat-exposure of protein solids at 70 °C caused minimum changes in secondary structure and biological activity was almost retained. However, thermal exposure of protein aqueous solution induced significant changes in the secondary structure indicated by area overlap values and caused considerable reduction in the biological activity. The changes in secondary structures were found to be in full alignment with the loss of biological activity for both protein solids as well as aqueous solutions. Catalase lost entire biological activity upon heating in the solution state. In conclusion, the findings of the present study indicate a direct correlation between protein secondary structure alterations and the retention of biological activity which can be taken into account during the development and delivery of protein drugs formulations.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  15. Zeeshan F, Tabbassum M, Jorgensen L, Medlicott NJ
    Appl Spectrosc, 2018 Feb;72(2):268-279.
    PMID: 29022355 DOI: 10.1177/0003702817739908
    Protein drugs may encounter conformational perturbations during the formulation processing of lipid-based solid dosage forms. In aqueous protein solutions, attenuated total reflection Fourier transform infrared (ATR FT-IR) spectroscopy can investigate these conformational changes following the subtraction of spectral interference of solvent with protein amide I bands. However, in solid dosage forms, the possible spectral contribution of lipid carriers to protein amide I band may be an obstacle to determine conformational alterations. The objective of this study was to develop an ATR FT-IR spectroscopic method for the analysis of protein secondary structure embedded in solid lipid matrices. Bovine serum albumin (BSA) was chosen as a model protein, while Precirol AT05 (glycerol palmitostearate, melting point 58 ℃) was employed as the model lipid matrix. Bovine serum albumin was incorporated into lipid using physical mixing, melting and mixing, or wet granulation mixing methods. Attenuated total reflection FT-IR spectroscopy and size exclusion chromatography (SEC) were performed for the analysis of BSA secondary structure and its dissolution in aqueous media, respectively. The results showed significant interference of Precirol ATO5 with BSA amide I band which was subtracted up to 90% w/w lipid content to analyze BSA secondary structure. In addition, ATR FT-IR spectroscopy also detected thermally denatured BSA solid alone and in the presence of lipid matrix indicating its suitability for the detection of denatured protein solids in lipid matrices. Despite being in the solid state, conformational changes occurred to BSA upon incorporation into solid lipid matrices. However, the extent of these conformational alterations was found to be dependent on the mixing method employed as indicated by area overlap calculations. For instance, the melting and mixing method imparted negligible effect on BSA secondary structure, whereas the wet granulation mixing method promoted more changes. Size exclusion chromatography analysis depicted the complete dissolution of BSA in the aqueous media employed in the wet granulation method. In conclusion, an ATR FT-IR spectroscopic method was successfully developed to investigate BSA secondary structure in solid lipid matrices following the subtraction of lipid spectral interference. The ATR FT-IR spectroscopy could further be applied to investigate the secondary structure perturbations of therapeutic proteins during their formulation development.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared/methods*
  16. Zeeshan F, Tabbassum M, Jorgensen L, Medlicott NJ
    AAPS PharmSciTech, 2018 Feb;19(2):769-782.
    PMID: 29134579 DOI: 10.1208/s12249-017-0883-1
    Protein biologics are prone to conformational changes during formulation development. Limited methods are available for conformational analysis of proteins in solid state and in the presences of formulation excipients. The aim of this study was to investigate the secondary structures of proteins encased in solid lipid matrices as a novel indicator of their stability upon in vitro release. Model proteins namely catalase and lysozyme were incorporated into lipid namely Precirol® AT05 (glycerol palmitostearate, melting point 58°C) at 30% w/w loading using melting and mixing and wet granulation methods. Attenuated total reflectance (ATR-FTIR) spectroscopy, size-exclusion chromatography (SEC) and biological activity analyses were performed. The information about secondary structure was acquired using second derivative analysis of amide-I band (1600-1700 cm-1). ATR analysis demonstrated interference of lipid spectrum with protein amide-I band which was subsequently subtracted to allow the analysis of the secondary structure. ATR spectra amide-I bands showed shifts peak band positions compared to native protein for matrices prepared using wet granulation. SEC analysis gave evidence of protein aggregation for catalase which was increased using wet granulation. The biological activity of catalase was statistically different from that of control and was affected by the incorporation method and was found to be in alignment with ATR spectral changes and extent of aggregation. In conclusion, ATR spectroscopy could analyze protein secondary structure in lipid matrices provided lipid interference was minimized. The ATR spectral changes and formation of aggregates can indicate the loss in biological activity of protein released from solid lipid matrices.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  17. Zamiri R, Zakaria A, Abbastabar H, Darroudi M, Husin MS, Mahdi MA
    Int J Nanomedicine, 2011;6:565-8.
    PMID: 21698083 DOI: 10.2147/IJN.S16384
    Silver nanoparticles were fabricated by ablation of a pure silver plate immersed in castor oil. A Nd:YAG-pulsed Q-switch laser with 1064-nm wavelength and 10-Hz frequency was used to ablate the plate for 10 minutes. The sample was characterized by ultraviolet-visible, atomic absorption, Fourier transform-infrared spectroscopies, and transmission electron microscopy. The results of the fabricated sample showed that the nanoparticles in castor oil were about 5-nm in diameter, well dispersed, and showed stability for a long period of time.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  18. Zaman R, Karim ME, Othman I, Zaini A, Chowdhury EH
    Pharmaceutics, 2020 Jul 29;12(8).
    PMID: 32751231 DOI: 10.3390/pharmaceutics12080710
    Oral delivery is considered as the most preferred and yet most challenging mode of drug administration; especially a fragile and sensitive peptide like insulin that shows extremely low bioavailability through the gastro-intestinal (GIT) route. To address this problem, we have designed a novel drug delivery system (DDS) using precipitation-induced Barium (Ba) salt particles. The DDS can load insulin molecules and transport them through the GIT route. There were several in vitro simulation tests carried out to prove the efficiency of Ba salt particles as oral delivery candidates. All three Ba salt particles (BaSO4, BaSO3, and BaCO3) showed very good loading of insulin (>70% in all formulations) and a degree of resistance throughout a wide range of pHs from basic to acidic conditions when assessed by spectrophotometry. Particles and insulin-associated particles were morphologically assessed and characterized using FE-SEM and FT-IR. A set of tests were designed and carried out with mucin to predict whether the particles are potentially capable of overcoming one of the barriers for crossing intestinal epithelium. The mucin binding experiment demonstrated 60-100% of mucin adhesion to the three different particles. FT-IR identifies the characteristic peaks for mucin protein, particles, and particle-mucin complex re-confirming mucin adhesion to the particles. Finally, the effectiveness of nano-insulin was tested on streptozotocin (STZ) induced diabetic rats. A short acting human insulin analog, insulin aspart, was loaded into Ba salt particles at a dose of 100 IU/Kg prior to oral administration. Among the three formulations, insulin aspart-loaded BaSO4 and BaCO3 particles dramatically reduced the existing hyperglycemia. BaSO4 with loaded Insulin showed an onset of glucose-lowering action within 1 hr, with blood glucose level measured significantly lower compared to the 2nd and 3rd h (p < 0.05). Insulin-loaded BaCO3 particles showed a significant decrease in blood glucose level at 1-2 h, although the glucose level started to show a slight rise at 3rd h and by 4th h, it was back to baseline level. However, although BaSO3 particles with loaded insulin showed a trend of reduction in blood glucose level, the reduction was not found to be significant (p < 0.05) at any point in time. Therefore, oral formulations of insulin/BaSO4 and insulin/BaCO3 particles were observed as effective as native insulin aspart subcutaneous formulation in terms of onset and duration of action. Further investigation will be needed to reveal bioavailability and mechanism of action of this novel Nano-Insulin formulations.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  19. Zalilah Murni Yunus, Norzila Othman, Rafidah Hamdan, Nurun Najwa Ruslan
    MyJurnal
    A combination of phosphoric acid (H3PO4) 20% v/v impregnation and carbonization method was employed to convert honeydew rind into activated carbons (ACPHDR) for Zn(II) and Cr(III) removal aqueous solution. The characterization of ACPDHR by N2 sorption, iodine number and Boehm analysis result 1272 m2/g surface area, 1174 mg/g and 1.13 mmol/g total acidic functional groups respectively. Fourier transform infrared (FTIR) and Field emission scanning electron microscopy-electron dispersed microscopy (FESEM-EDX) analysis of unloaded and metal-loaded carbon showed shifted of significance peaks and the changes of surface morphology of the sorbent. The adsorption was optimized at pH, shaking duration, initial metal concentration and mass of adsorbent of 5.5, 40 min and 500 mg/L, 0.4 g for Zn(II) and 4, 40 min, 1000 mg/L, 0.1 g for Cr(III) removal. It is concluded that the metal removal was influenced by pH solution, contact time, initial metal concentration and mass of adsorbent. The highest removal of Zn(II) and Cr(III) was observed at 84.24% and 90.10% respectively. Waste from honeydew will be benefited from this research which offer a cheaper alternative precursor to coal based activated carbons.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  20. Zakiyah, L.K., Gui, M.M., Foo, R.S., Mohamed, A.R., Chai, S.P.
    ASM Science Journal, 2011;5(2):91-100.
    MyJurnal
    The functionalization of pristine CNTs is necessary for carbon nanotubes (CNTs) to be fully utilized, with the aim of increasing the nanotube reactivity and solubility in aqueous solutions. In this study, multi-walled carbon nanotubes (MWCNTs) were functionalized with a carboxylic group as this was an important step prior to application. The carboxylic group-functionalization was conducted through acid treatment, using sulphuric and nitric acids mixed at a ratio of 3:1 (v/v) and sonication for 30 min under different temperatures and time durations. The functionalization conditions of 50ºC x 5 h and 60ºC x 3 h were identified to be most suitable for introducing a carboxylic group onto the nanotube surfaces. The percentage of total weight loss due to the carboxylic group on the MWCNTs treated at 50ºC x 5 h and 60ºC x 3 h obtained from the thermogravimetric analysis was 13.26% and 13.76%, respectively. For both samples, peaks corresponding to the carboxylic group were identified in the FT-IR spectra. The changes in the morphology of the treated MWCNTs were also observed under SEM analysis.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
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