Azalina Mohamed Nasir
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Azalina Mohamed Nasir
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Azalina Mohamed, Nasir
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Azalina, M. N.
Nasir, Azalina Mohamed
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56785467700

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Epitope imprinted polymer on silica microparticle for heparin purification

2016 , Azalina Mohamed Nasir

Heparin, is a sulfated glycosaminoglycan (GAG) used as an anticoagulant and antithrombotic agent, is widely employed in hemodialysis and surgery. Heparin is extracted from animal source therefore, oversulfated chondroitin sulfate (OSCS) is impurity that may be present at low levels in pharmaceutical heparin products which, associated with side effects and death in some cases. Hence, it is important to purify heparin in order to reduce these side effects. For this purpose, molecule imprinted polymer (MIP) extraction approach may offer some advantages. A macromolecule such as heparin, an epitope imprinting is advantageous to increase the affinity of heparin separation and had been developed in this study. The heparin epitope imprinted polymer was employed via sol gel process, in which macroparticle silica gel was used as a binder. This work emphasized ftrstly on the investigation of the strength of interaction between the template (glucose sulfate) with three different functionalized silane as a functional monomer. A batch adsorption study shown that methylimidazole as a functional monomer had the highest binding capacity of 53.07 mg/g, whereas the amine possessed high imprinting factor (IF; 2.24). In the second part of the study, the epitope imprinting was implemented using low molecular weight heparin (LMWH) as a template. During the development of epitope imprinting, template bleeding was identified that interfered the binding performance. Thus, a mixture of MeOH:HCl solvent and either stirring or ultrasonic extraction techniques could overcome the template bleeding problems. Later, the optimization of epitope imprinting process were investigated for the development of heparin epitope imprinting. The significant binding capacity of heparin (19.48 mg/g) compared with LMWH (2.50 mg/g) suggested that the epitope surface-imprinted polymer using water as a porogenic solvent with the ratio 1:2 of template to functional monomer successfully adsorbed and enriched the heparin. The adsorption behavior of epitope imprinting indicated that Langmuir-Freundlich (single-site) was considered as the model with better ftting and kinetic batch studies showed pseudo-first-order kinetic model via physicochemical process. Final part of the study, an anticoagulant drug from local pharmaceutical industry was tested for the extraction and separation of heparin and OSCS on the molecularly imprinted solid phase extraction (MISPE). The mobile phase solvent necessary to perform the separation was optimized and results showed that ACN :H20 and MeOH:H20 of ratio 1:1, phosphate buffer pH 5, and ammonium chloride (NH4Cl) were selected as the suitable loading, washing, and modifier respectively in the elution solvent. Finally, the recovery of heparin in MISPE column was increased to 52.33% after increasing the solvent volume to two times of 1.0 mL eluting olvent. In conclusion, epitope surface-imprinted polymer was proven to be a promising resin for heparin purification in the pharmaceutical industry.

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OPTIMIZATION OF DIFFERENT PARAMETERS IN THE SYNTHESIS OF BISPHENOL A IMPRINTED POLYMER VIA PRECIPITATION POLYMERIZATION FOR BISPHENOL A ADSORPTION

2021-12-01 , Nee T.N. , Noorhidayah Ishak , Azalina Mohamed Nasir , Nur Zatul 'Iffah Zakaria , Nor Munirah Rohaizad

Molecularly imprinted polymer (MIP) is used to synthesize receptors and is highly recognized against target molecules. The purpose of the study is to prepare bisphenol A (BPA) imprinted polymer that can be used to adsorb BPA molecules. The MIP was prepared by precipitation polymerization using BPA as a template, methacrylic acid (MAA) as a functional monomer, ethylene glycol dimethacrylate (EGDMA) as a crosslinker, acetonitrile as a solvent, and 1,1'-azobis(cyclohexanecarbonitrile) (AIBN) as an initiator by heating in an oil bath at 60 °C for 20 hours. The influence of several parameters (i.e., the ratio of monomer-template, the amount of crosslinker, and the amount of solvent) on the recognition capability of BPA MIP was investigated using response surface methodology (RSM). The optimal conditions of BPA synthesis are 3 mmol of monomer, 30 mmol of crosslinker, and 35 mL of solvent, which achieved an adsorption capacity of 78.111 mg/g. The MIP and non-imprinted polymer (NIP) were characterized using Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The MIP shows higher selectivity towards BPA compared to other analogs. In conclusion, the particles of imprinted polymer have a great potential in the adsorption of BPA.

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Screening of polymer precursors for preparation of nitrate imprinted polymer

2020 , Noorhidayah Ishak , Mohd Noor Ahmad , A K M Shafiqul Islam , Azalina Mohamed Nasir , Muhammad Syafie Ahmad , Siti Fatimah Kamaruddin

The molecular imprinting technique (MIT) has received considerable attention in the development of anion recognition materials which can be used in different applications. Major difficulty in molecular imprinting polymer is the selection of suitable polymer precursor such as template, type of monomer, amount of monomer and crosslinker that may influence the nitrate imprinted polymer (IIP) preparation. The main purpose of this study is to evaluate the optimum parameters (type of template, type of monomer, amount monomer and crosslinker) during polymerization process. The optimum polymer particles were prepared by bulk polymerization using sodium nitrate as a template, allylthiourea as functional monomer, ethylene glycol dimethacrylate (EGDMA) as a cross linker and acetonitrile and dimethylsulfoxide as solvent by heating in an oil bath at 60 °C for 20 hour. The non imprinted polymer (NIP) was synthesized using the same method but without template molecule. The optimal condition of nitrate imprinted polymer synthesis was 3 mmol of monomer, 20 mmol of cross linker and 6 ml of solvent used with adsorption capacity of 14.06 mg/g and 1.27 imprinting factor. The IIP and NIP were characterized using Fourier transform infrared (FTIR) spectroscopy. The FTIR analysis were showed that IIP and NIP were successfully synthesized. As conclusion from this research shows that the IIP produced has potential in to be used as nitrate adsorption in aqueous water.

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β-Glucan extraction from mycelium in spent mushroom substrate of pleurotus ostreatus and schizophyllum commune

2021-05-24 , Azalina Mohamed Nasir , Ruslan N.R.N. , Zakaria Z. , Hassan S.A.M. , Ishak N. , Nor Munirah Rohaizad , Ahmad Anas Nagoor Gunny

Spent mushroom substrate (SMS) is the biomass waste produced from the production of mushroom which generating disposal problems. To overcome the problem the extraction of bioactive compound such as β-glucan from the waste SMS could solve the problem and can also increase its added value. β-glucan appears to be promising for aiding in the cure of tumorous disease and help to reduce the cholesterol levels in blood. In this study, β-glucan was extracted and compared from two different commercial mushroom (Pleurotus ostreatus and Schizophyllum commune) from its fruiting body and mycelium on solid waste SMS using chemical extraction methods. The characteristics of physical structure, functional group and properties of extracted β-glucan was investigated. Here, Fourier-transform infrared (FTIR) and screening electron microscope (SEM) were used to identify and evaluated the structural conformations of β-glucan and physical structure. The functional properties, swelling power, viscosity and fat binding capacity were analyzed. Based on results, mycelia of Pleurotus ostreatus shown highest swelling power (11.74 g/g) and fat binding capacity (12.09 g oil/g sample) while, mycelia of Schizophyllum commune shown the highest viscosity (11.85 cP). Since the value for all functional properties shown the highest value on mycelium compare to fruiting body, thus it is strength that β-glucan extraction from mycelium solid waste has high novel properties compare with mushroom fruiting body.

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Deep Eutectic Solvent-Assisted Synthesis of Nanocrystalline Cellulose Adsorbent for Silver Nitrate Removal

2023-01-01 , Ahmad Anas Nagoor Gunny , Aminuddin N.H. , Azalina Mohamed Nasir , Hashim R.H.R. , Jalil M.F.A. , Pakir M.A.A.S. , Mohamed Mydin Hj M.Abdul Kader , Rahman A.

This study introduces application of deep eutectic solvent-assisted of nanocrystalline cellulose adsorbent for silver nitrate removal. The study aims to offer new green and low energy method in producing nano crystalline cellulose (NCC). NCC from microcrystalline cellulose (MCC) was extracted by using synthesized acidic DES. NCC fabricated was found to have a capability to act as a biosorbent for removal of silver nitrate (AgNO3). The adsorption kinetics and isotherm of silver nitrate on NCC were studied by varies initial concentration of silver nitrate and contact time. The experimental data were analyzed by using Langmuir and Freundlich models of adsorption. The adsorption isotherm data were fitted well to Freundlich adsorption isotherm. The biosorption kinetics data obtained at different time have been analyzed using pseudo-first order and pseudo-second order equation. The experimental data fitted well to pseudo-second order kinetics model. Application of novel and green acidic DES for production of NCC from lignocellulose will contribute to a new paradigm in a green adsorption study.

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One-pot synthesis of molecular-imprinted membrane for selective extraction of caffeic acid

2020-08-01 , Azalina Mohamed Nasir , Noorhidayah Ishak , Said M.S.M. , Mohd Irfan Hatim Mohamed Dzahir

This research investigated the capabilities of caffeic acid-imprinted membrane (CA-IM) toward the selective extraction of caffeic acid (CA). A simpler surface-imprinted membrane using poly(vinylidene fluoride) as supporting membrane, CA as the template, ethylene glycol dimethacrylate as the cross-linker, and 4-vinylpyridine as the functional monomer was developed. The characterization of the membrane’s surface after the polymerization process was analyzed with Fourier transform infrared spectroscopy and a scanning electron microscope. Molecular modeling showed a ratio of 1:4 for which template/monomer gave the highest at − 18.09 kcal/mol. This indicates that this ratio can form a stable complex and a greater affinity toward CA. Batch rebinding and kinetics were performed and then followed by isotherm and kinetic adsorption modeling. Our results show that CA-IM fitted with Freundlich adsorption model and kinetic adsorption of CA-IM followed the second-order model. The selectivity experiment indicated that the adsorption capacity (1.497 mg/g), distribution coefficients, KD (1.939), and selectivity of polymers to CA were higher than for gallic acid and vanillic acid for CA-IM when compared to NIM. These results demonstrated that CA-IM is a capable and effective material for the selective adsorption and enrichment of CA compounds.

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Optimization of different parameter in synthesis ion imprinted polymers via precipitation polymerization for nitrate adsorption

2020 , Noorhidayah Ishak , Teh Chin Xin , Shuit Siew Hoong , Azalina Mohamed Nasir

An important issue in synthesis of ion imprinted polymers (IIP) is optimization of the main parameters that involved during polymerization process as those parameters can influence the performance of IIP. In this study, IIP was synthesized by precipitation polymerization using allylthiourea (ATU) as monomer, nitrate as template ion, ethylene glycol dimethacrylate (EGDMA) as crosslinker, 2,2'-azobisisobutyronitrile (AIBN) as initiator with 365 nm ultraviolet (UV) light and mixture of acetonitrile and dimethylsulfoxide (DMSO) as porogenic solvent. The influences of various polymerization parameters in the synthesis of IIPs were investigated. The parameters studied included: ratio of monomer-template, amount of crosslinker and amount of porogenic solvent. These parameters were optimized using response surface methodology (RSM) coupled with central composite design CCD). Results showed that IIP with an optimum adsorption capacity of 156.233 mg/g of nitrate ion NO3-) can be obtained under the following polymerization conditions: 3.90 mmol of ATU, 18.67 mmol of EGDMA and 38.30 mL of porogenic solvent. The nitrate imprinted polymer and non-imprinted polymer were characterized by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The SEM micrograph showed microparticles ranging from 14.05 - 16.17 µm in diameter and the surface was rough and porous. The sorption of IIP followed Langmuir adsorption isotherm model. In this study, the binding capacity indicated that nitrate imprinted polymer recognized NO3- in aqueous solution more effectively compared to non-imprinted polymer and this polymer particles potrayed better adsorption as compared other adsorbent

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Synthesis and optimization studies of Fructose palmitate

2010 , Azalina Mohamed Nasir

Fructose palmitate (sugar ester) is a relatively new class of nonionic surfactants. Their excellent biodegradability and low toxicity surfactant as well as effectiveness at extreme temperature, pH and salinity show their increasing importance in numerous areas of application. For a long time, large scale production of sugar ester was dominated by conventional chemical processing. However, the conventional chemical process leaves out bad impact to the human and environment. Compared to the enzymatic synthesis, this process offers a safer and easier alternative. In the present work, sugar ester production was developed by a novel and effective enzymatic method which can reduce the advantages of conventional chemical process. Direct unprotected sugar and non activated fatty acid were used as a starting material. Combination of supersaturated sugar solution under anhydrous condition and stepwise addition of molecular sieve as water absorbent agent during the reaction were found to be a suitable method in increasing the reaction rate and fatty acid conversion. In this method, influences of several parameters were investigated as a screening to the optimization process. Results from screening were used to optimize and analyze fructose palmitate (sugar ester) esterification using a response surface methodology (RSM) based on central composite design (CCD). The 98.58 ± 0.52% of optimum fatty acid conversion was determined by 11.92% (w/w of substrates) immobilized enzyme loading, 0.50M fatty acid concentration, 10.0h reaction time and 53.67oC of reaction temperature. The reusability of the immobilized enzyme was shown good conversion, were greater than 88% of fatty acid conversion after 10th reaction cycles without additional treatment of the immobilized enzyme.

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Heparin Epitope Imprinted Via Sol-Gel Process on Silica Surface: Effect of Template: Monomer Ratio Studies

2023-01-01 , Azalina Mohamed Nasir , Ishak N. , Anuar A. , Abdullah S.

Heparin, a sulfated glycosaminogylcan (GAG) is one of macromolecule natural compounds and widely used as an anticoagulant drug, anti-thrombotic agent and hemodialysis (patients undergoing kidney dialysis). Since it is derived from animal source, heparin can contain several natural contaminants. Thus, molecular imprinting technology is introduced for purification and separation of heparin. An epitope extraction was implemented consist of low molecular weight heparin (LMWH) as template to capture large molecule of heparin which prepared by sol-gel process on the surface of macromolecule silica using 3-aminopropyltriethoxysilane (APTES) and tetraethoxysilane (TEOS) and functional monomer and cross-linker respectively. Here, the effect of template: monomer ratio was evaluated and result shown that the (1:2) ratio of template to functional monomer successfully adsorb and enrich the heparin protein. The imprinted polymer was characterized with Fourier Transform Infrared (FTIR) spectroscopy, Thermogravimetric Analysis (TGA), Brunauer-Emmet-Teller (BET) and Field Emission Scanning Electron Microscopy (FESEM). The adsorption behaviours of epitope imprinting indicated that Langmuir-Freundlich (single-site) was considered as the model with better fit and kinetic batch studies showed pseudo-first-order kinetic model via physicochemical process. The results obtained good imprinting comparable of epitope imprinting effect.

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Optimization of different parameter in synthesis ion imprinted polymers via precipitation polymerization for Nitrate adsorption

2020 , Noorhidayah Ishak , Teh Chin Xin , Shuit Siew Hoong , Azalina Mohamed Nasir

An important issue in synthesis of ion imprinted polymers (IIP) is optimization of the main parameters that involved during polymerization process as those parameters can influence the performance of IIP. In this study, IIP was synthesized by precipitation polymerization using allylthiourea (ATU) as monomer, nitrate as template ion, ethylene glycol dimethacrylate (EGDMA) as crosslinker, 2,2'-azobisisobutyronitrile (AIBN) as initiator with 365 nm ultraviolet (UV) light and mixture of acetonitrile and dimethylsulfoxide (DMSO) as porogenic solvent. The influences of various polymerization parameters in the synthesis of IIPs were investigated. The parameters studied included: ratio of monomer-template, amount of crosslinker and amount of porogenic solvent. These parameters were optimized using response surface methodology (RSM) coupled with central composite design CCD). Results showed that IIP with an optimum adsorption capacity of 156.233 mg/g of nitrate ion NO3-) can be obtained under the following polymerization conditions: 3.90 mmol of ATU, 18.67 mmol of EGDMA and 38.30 mL of porogenic solvent. The nitrate imprinted polymer and non-imprinted polymer were characterized by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The SEM micrograph showed microparticles ranging from 14.05 - 16.17 µm in diameter and the surface was rough and porous. The sorption of IIP followed Langmuir adsorption isotherm model. In this study, the binding capacity indicated that nitrate imprinted polymer recognized NO3- in aqueous solution more effectively compared to non-imprinted polymer and this polymer particles potrayed better adsorption as compared other adsorbent in aqueous solution more effectively compared to non-imprinted polymer and this polymer particles potrayed better adsorption as compared other adsorbent

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