Displaying publications 1 - 20 of 148 in total

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  1. Fulltext Ion-imprinted membranes for lithium recovery: A review
    Zavahir S, Riyaz NS, Elmakki T, Tariq H, Ahmad Z, Chen Y, et al.
    Chemosphere, 2024 Apr;354:141674.
    PMID: 38462186 DOI: 10.1016/j.chemosphere.2024.141674
    This review critically examines the effectiveness of ion-imprinted membranes (IIMs) in selectively recovering lithium (Li) from challenging sources such as seawater and brine. These membranes feature customized binding sites that specifically target Li ions, enabling selective separation from other ions, thanks to cavities shaped with crown ether or calixarene for improved selectivity. The review thoroughly investigates the application of IIMs in Li extraction, covering extensive sections on 12-crown-4 ether (a fundamental crown ether for Li), its modifications, calixarenes, and other materials for creating imprinting sites. It evaluates these systems against several criteria, including the source solution's complexity, Li+ concentration, operational pH, selectivity, and membrane's ability for regeneration and repeated use. This evaluation places IIMs as a leading-edge technology for Li extraction, surpassing traditional methods like ion-sieves, particularly in high Mg2+/Li+ ratio brines. It also highlights the developmental challenges of IIMs, focusing on optimizing adsorption, maintaining selectivity across varied ionic solutions, and enhancing permselectivity. The review reveals that while the bulk of research is still exploratory, only a limited portion has progressed to detailed lab verification, indicating that the application of IIMs in Li+ recovery is still at an embryonic stage, with no instances of pilot-scale trials reported. This thorough review elucidates the potential of IIMs in Li recovery, cataloging advancements, pinpointing challenges, and suggesting directions for forthcoming research endeavors. This informative synthesis serves as a valuable resource for both the scientific community and industry professionals navigating this evolving field.
  2. Fulltext LINAC based radiosurgery and radiotherapy for neurosurgical diseases: what have we learnt so far
    Zamzuri I, Badrisyah I, Rahman GI, Pal HK, Muzaimi M, Jafri AM, et al.
    Med J Malaysia, 2011 Oct;66(4):346-9.
    PMID: 22299555 MyJurnal
    Stereotactic radiosurgery uses a single fraction high dose radiation while stereotactic radiotherapy uses multifractionated lower dose focused radiation.
  3. Fulltext Mechanism(s) of action underlying the gastroprotective effect of ethyl acetate fraction obtained from the crude methanolic leaves extract of Muntingia calabura
    Zakaria ZA, Balan T, Azemi AK, Omar MH, Mohtarrudin N, Ahmad Z, et al.
    BMC Complement Altern Med, 2016 Feb 24;16:78.
    PMID: 26912079 DOI: 10.1186/s12906-016-1041-0
    BACKGROUND: Muntingia calabura L. (family Muntingiaceae), commonly known as Jamaican cherry or kerukup siam in Malaysia, is used traditionally to treat various ailments. The aim of this study is to elucidate the possible underlying gastroprotective mechanisms of ethyl acetate fraction (EAF) of Muntingia calabura methanolic leaves extract (MEMC).

    METHODS: MEMC and its fractions were subjected to HPLC analysis to identify and quantify the presence of its phyto-constituents. The mechanism of gastroptotection of EAF was further investigated using pylorus ligation-induced gastric lesion rat model (100, 250, and 500 mg/kg). Macroscopic analysis of the stomach, evaluation of gastric content parameters such as volume, pH, free and total acidity, protein estimation, and quantification of mucus were carried out. The participation of nitric oxide (NO) and sulfhydryl (SH) compounds was evaluated and the superoxide dismutase (SOD), gluthathione (GSH), catalase (CAT), malondialdehyde (MDA), prostaglandin E2 (PGE2) and NO level in the ethanol induced stomach tissue homogenate was determined.

    RESULTS: HPLC analysis confirmed the presence of quercetin and gallic acid in EAF. In pylorus-ligation model, EAF significantly (p <0.001) prevent gastric lesion formation. Volume of gastric content and total protein content reduced significantly (p 

  4. Fulltext PFO-DBT:MEH-PPV:PC₇₁BM ternary blend assisted platform as a photodetector
    Zafar Q, Ahmad Z, Sulaiman K
    Sensors (Basel), 2015;15(1):965-78.
    PMID: 25574936 DOI: 10.3390/s150100965
    We present a ternary blend-based bulk heterojunction ITO/PEDOT:PSS/PFO-DBT: MEH-PPV:PC71BM/LiF/Al photodetector. Enhanced optical absorption range of the active film has been achieved by blending two donor components viz. poly[2,7-(9,9-di-octyl-fluorene)-alt-4,7-bis(thiophen-2-yl)benzo-2,1,3-thiadiazole] (PFO-DBT) and poly(2-methoxy-5(2'-ethylhexyloxy) phenylenevinylene (MEH-PPV) along with an acceptor component, i.e., (6,6)-phenyl-C71 hexnoic acid methyl ester. The dependency of the generation rate of free charge carriers in the organic photodetector (OPD) on varied incident optical power density was investigated as a function of different reverse biasing voltages. The photocurrent showed significant enhancement as the intensity of light impinging on active area of OPD is increased. The ratio of Ilight to Idark of fabricated device at -3 V was ~3.5 × 10(4). The dynamic behaviour of the OPD under on/off switching irradiation revealed that sensor exhibits quick response and recovery time of ∼800 ms and 500 ms, respectively. Besides reliability and repeatability in the photoresponse characteristics, the cost-effective and eco-friendly fabrication is the added benefit of the fabricated OPD.
  5. Understanding the breast cancer experience: a qualitative study of Malaysian women
    Yusuf A, Ab Hadi IS, Mahamood Z, Ahmad Z, Keng SL
    Asian Pac J Cancer Prev, 2013;14(6):3689-98.
    PMID: 23886167
    Breast cancer is the most common and leading cause of cancer mortality among Malaysian women. Despite good survival rates, the diagnosis of cancer still invokes the feeling of stress, fear and uncertainty. Because very little is known about the experiences of Malaysian women with breast cancer, a qualitative study using semi- structured interviews to explore the lived experience of newly diagnosed breast cancer. Using a purposive sampling method, 20 Malaysian women newly diagnosed with breast cancer, including Malays (n=10) and Chinese (n=10) were recruited in two main public hospitals in Kelantan. Similarities and divergence in women's experience were identified through thematic analysis of interview transcripts. Three themes emerged from the data: uncertainty experience of the illness, transition process and fatalistic view of breast cancer. In many ways, these findings were parallel with previous studies, suggesting that the experience of breast cancer is to a certain extent similar among women newly diagnosed with breast cancer. This study adds to the sparse literature concerning the experience of illness following breast cancer diagnosis among the Malays and Chinese. More importantly, this study addressed areas that were previously lacking, specifically in depth information on breast cancer experience from a developing country with a multi-ethnic population. The results of this investigation provide preliminary information to healthcare professionals on the impact of illness and cultural influence on survivorship to plan for appropriate education and supportive programme in order to meet the needs of breast cancer women more effectively.
  6. Quality of life in Malay and Chinese women newly diagnosed with breast cancer in Kelantan, Malaysia
    Yusuf A, Ahmad Z, Keng SL
    Asian Pac J Cancer Prev, 2013;14(1):435-40.
    PMID: 23534769
    BACKGROUND: Breast cancer is the leading cause of cancer-related death among women in Malaysia. A diagnosis is very stressful for women, affecting all aspects of their being and quality of life. As such, there is little information on quality of life of women with breast cancer across the different ethnic groups in Malaysia. The purpose of this study was to examine the quality of life in Malay and Chinese women newly diagnosed with breast cancer in Kelantan.

    MATERIALS AND METHODS: A descriptive study involved 58 Malays and 15 Chinese women newly diagnosed with breast cancer prior to treatment. Quality of life was measured using the Malay version of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30) and its breast-specific module (QLQ-BR23). Socio-demographic and clinical data were also collected. All the data were analyzed using SPSS version 20.0.

    RESULTS: Most of the women were married with at least a secondary education and were in late stages of breast cancer. The Malay women had lower incomes (p=0.046) and more children (p=0.001) when compared to the Chinese women. Generally, both the Malay and Chinese women had good functioning quality-of-life scores [mean score range: 60.3-84.8 (Malays); 65.0-91.1 (Chinese)] and global quality of life [mean score 60.3, SD 22.2 (Malays); mean score 65.0, SD 26.6 (Chinese)]. The Malay women experienced more symptoms such as nausea and vomiting (p=0.002), dyspnoea (p=0.004), constipation (p<0.001) and breast-specific symptoms (p=0.041) when compared to the Chinese.

    CONCLUSIONS: Quality of life was satisfactory in both Malays and Chinese women newly diagnosed with breast cancer in Kelantan. However, Malay women had a lower quality of life due to high general as well as breast-specific symptoms. This study finding underlined the importance of measuring quality of life in the newly diagnosed breast cancer patient, as it will provide a broader picture on how a cancer diagnosis impacts multi-ethnic patients. Once health care professionals understand this, they might then be able to determine how to best support and improve the quality of life of these women during the difficult times of their disease and on-going cancer treatments.

  7. Fulltext Nutrition education and knowledge, attitude and hemoglobin status of Malaysian adolescents
    Yusoff H, Daud WN, Ahmad Z
    Southeast Asian J. Trop. Med. Public Health, 2012 Jan;43(1):192-200.
    PMID: 23082570
    A higher occurrence of iron deficiency anemia is present in rural Malaysia than urban Malaysia due to a lower socio-economic status of rural residents. This study was conducted in Tanah Merah, a rural district of Kelantan, Malaysia. Our objective was to investigate the impact of nutrition education alone, daily iron, folate and vitamin C supplementation or both on knowledge, attitudes and hemoglobin status of adolescent students. Two hundred eighty fourth year secondary students were each assigned by school to 1 of 4 different treatment groups. Each intervention was carried out for 3 months followed by 3 months without treatment. A validated self-reported knowledge and attitude questionnaire was administered; hemoglobin levels were measured before and after intervention. At baseline, no significant difference in hemoglobin was noted among the 4 groups (p = 0.06). The changes in hemoglobin levels at 3 months were 11, 4.6, 3.9 and -3.7% for the supplementation, nutrition education, combination and control groups, respectively. The changes at 6 months were 1.0, 6.8, 3.7 and -14.8%, respectively. Significant improvements in knowledge and attitude were evidenced in both the nutritional education and combination groups. The supplementation and control groups had no improvement in knowledge or attitudes. This study suggests nutritional education increases knowledge, attitudes and hemoglobin levels among Malaysian secondary school adolescents.
  8. Effectiveness of Nutrition Education vs. Non-Nutrition Education Intervention in Improving Awareness Pertaining Iron Deficiency among Anemic Adolescents
    Yusoff H, Wan Daud WN, Ahmad Z
    Iran J Public Health, 2013;42(5):467-71.
    PMID: 23802103
    This study was carried out to compare the effect between nutrition education intervention and non-nutrition education intervention on awareness regarding iron deficiency among schooling adolescents in Tanah Merah, one of rural district in Kelantan, Malaysia.
  9. Fulltext Suppressions of serotonin-induced increased vascular permeability and leukocyte infiltration by Bixa orellana leaf extract
    Yong YK, Sulaiman N, Hakim MN, Lian GE, Zakaria ZA, Othman F, et al.
    Biomed Res Int, 2013;2013:463145.
    PMID: 24224164 DOI: 10.1155/2013/463145
    The aim of the present study was to evaluate the anti-inflammatory activities of aqueous extract of Bixa orellana (AEBO) leaves and its possible mechanisms in animal models. The anti-inflammatory activity of the extract was evaluated using serotonin-induced rat paw edema, increased peritoneal vascular permeability, and leukocyte infiltrations in an air-pouch model. Nitric oxide (NO), indicated by the sum of nitrites and nitrates, and vascular growth endothelial growth factor (VEGF) were measured in paw tissues of rats to determine their involvement in the regulation of increased permeability. Pretreatments with AEBO (50 and 150 mg kg⁻¹) prior to serotonin inductions resulted in maximum inhibitions of 56.2% of paw volume, 45.7% of Evans blue dye leakage in the peritoneal vascular permeability model, and 83.9% of leukocyte infiltration in the air-pouch model. 57.2% maximum inhibition of NO and 27% of VEGF formations in rats' paws were observed with AEBO at the dose of 150 mg kg⁻¹. Pharmacological screening of the extract showed significant (P < 0.05) anti-inflammatory activity, indicated by the suppressions of increased vascular permeability and leukocyte infiltration. The inhibitions of these inflammatory events are probably mediated via inhibition of NO and VEGF formation and release.
  10. Fulltext Chemical constituents and antihistamine activity of Bixa orellana leaf extract
    Yong YK, Zakaria ZA, Kadir AA, Somchit MN, Ee Cheng Lian G, Ahmad Z
    BMC Complement Altern Med, 2013;13:32.
    PMID: 23410184 DOI: 10.1186/1472-6882-13-32
    Bixa orellana L. has been traditionally used in Central and South America to treat a number of ailments, including internal inflammation, and in other tropical countries like Malaysia as treatment for gastric ulcers and stomach discomfort. The current study aimed to determine the major chemical constituents of the aqueous extract of B. orellana (AEBO) and to evaluate the antihistamine activity of AEBO during acute inflammation induced in rats.
  11. Fulltext Bixa orellana leaf extract suppresses histamine-induced endothelial hyperpermeability via the PLC-NO-cGMP signaling cascade
    Yong YK, Chiong HS, Somchit MN, Ahmad Z
    BMC Complement Altern Med, 2015;15:356.
    PMID: 26468073 DOI: 10.1186/s12906-015-0901-3
    Histamine is established as a potent inflammatory mediator and it is known to increased endothelial permeability by promoting gap formation between endothelial cells. Previous studies have shown that aqueous extract of Bixa orellana leaves (AEBO) exhibits antihistamine activity in vivo, yet the mechanism of its action on endothelial barrier function remains unclear. Therefore, the current study aimed to determine the protective effect of AEBO against histamine-induced hyperpermeability in vitro.
  12. Fulltext Clinacanthus nutans Extracts Are Antioxidant with Antiproliferative Effect on Cultured Human Cancer Cell Lines
    Yong YK, Tan JJ, Teh SS, Mah SH, Ee GC, Chiong HS, et al.
    Evid Based Complement Alternat Med, 2013;2013:462751.
    PMID: 23533485 DOI: 10.1155/2013/462751
    Clinacanthus nutans Lindau leaves (CN) have been used in traditional medicine but the therapeutic potential has not been explored for cancer prevention and treatment. Current study aimed to evaluate the antioxidant and antiproliferative effects of CN, extracted in chloroform, methanol, and water, on cancer cell lines. Antioxidant properties of CN were evaluated using DPPH, galvinoxyl, nitric oxide, and hydrogen peroxide based radical scavenging assays, whereas the tumoricidal effect was tested on HepG2, IMR32, NCL-H23, SNU-1, Hela, LS-174T, K562, Raji, and IMR32 cancer cells using MTT assay. Our data showed that CN in chloroform extract was a good antioxidant against DPPH and galvinoxyl radicals, but less effective in negating nitric oxide and hydrogen peroxide radicals. Chloroform extract exerted the highest antiproliferative effect on K-562 (91.28 ± 0.03%) and Raji cell lines (88.97 ± 1.07%) at 100  μ g/ml and the other five cancer cell lines in a concentration-dependent manner, but not on IMR-32 cells. Fourteen known compounds were identified in chloroform extract, which was analysed by gas chromatography-mass spectra analysis. In conclusion, CN extracts possess antioxidant and antiproliferative properties against cultured cancer cell lines, suggesting an alternate adjunctive regimen for cancer prevention or treatment.
  13. Fulltext Clinical significance of Mantoux test in Malaysian patients
    Yaacob I, Ahmad Z
    Med J Malaysia, 1990 Sep;45(3):231-4.
    PMID: 2152084
    The value of tuberculin skin testing in the diagnosis of active tuberculosis remains uncertain. Interpretation of tuberculin tests would be easier if the tuberculin test profiles in different communities were accurately known. We reviewed 468 Mantoux test reactions in patients coming to Hospital Universiti Sains Malaysia with suspected tuberculosis. Eighty six percent of patients with active tuberculosis had a positive Mantoux test. Forty two percent of the cases of positive Mantoux test did not have evidence of active tuberculosis. Most of these cases had evidence of past infection with tuberculosis. We conclude that Mantoux test is a sensitive but a non-specific test in the diagnosis of active tuberculosis.
    Study site: outpatients, inpatients; Hospital Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia
  14. Fulltext Lung cancer in Kelantan
    Yaacob I, Ahmad Z, Harun Z
    Med J Malaysia, 1990 Sep;45(3):220-4.
    PMID: 1966930
    A review of 119 patients (88 males and 31 females) with carcinoma of the lung seen at the Hospital University Sains Malaysia (HUSM) from 1984 to 1989 was done. The mean age of the patients was 60.3 years with a high proportion (76.6%) of them were between 41 and 70 years. Seventy five percent of patients (84% of men and 26% of women) were smokers. The Chinese have a significantly higher preponderance to carcinoma of the lung. The commonest histological type found was squamous cell carcinoma in men and adenocarcinoma in women. Small cell carcinoma was uncommon. Squamous cell and large cell/undifferentiated type of carcinoma were significantly associated with smoking behaviour of the patients.
  15. Fulltext Fibreoptic bronchoscopy--a Malaysian experience
    Yaacob I, Harun Z, Ahmad Z
    Singapore Med J, 1991 Feb;32(1):26-8.
    PMID: 2017700
    Two hundred and ninety-three bronchoscopies were done for 285 patients (78% males, 22% females) at Hospital University Sains Malaysia between 1984 and 1988. The mean age was 56.4 years (range 13 to 90 years). 70.2% of patients underwent bronchoscopies to confirm or exclude the diagnosis of carcinoma of the bronchus, out of which 58% were confirmed to have bronchial carcinoma. 77% of the 98 patients with visible endobronchial tumours had biopsy specimens diagnostic of malignancy. Brushing and washing cytology increased the positive yield to 92%. The commonest histological type of bronchial carcinoma identified was squamous cell carcinoma (48.1%), followed by small cell carcinoma (27.1%), anaplastic/undifferentiated carcinoma (12.9%), adenocarcinoma (9.4%) and large cell carcinoma (2.4%). Bronchoscopy for the investigation of haemoptysis identified the commonest cause as 'bronchitis'. There were no complications noted in our series. Notable differences of our experience compared to that of the western series were the high percentage of bronchoscopy done for infective respiratory disorders and the younger age of our patients.
  16. Fulltext Concentrations of Mn and Fe in the sediment cores of Sarawak and Sabah coastal waters. [Kepekatan Mn dan Fe dalam teras sedimen di perairan Sarawak dan Sabah.]
    Wan Mahmood ZU, Ahmad Z, Mohamed CAR
    Sains Malaysiana, 2010;39(1):13-20.
    Sediment cores were taken at eight stations along Sarawak and Sabah coastal waters using a gravity box corer on July 2004. The sediment cores were cut into 2 cm interval for measurement of Mn and Fe concentration using the Inductive Couple Plasma-Mass Spectrometer (ICP-MS). Overall, the sediment cores contained much mud which include a mixture of silt (46 – 67%) and clay (18 – 53%) compared to sand (0.4 – 16%). The concentrations of Mn and Fe were in the range of 154 – 366 µg/g and 0.9 – 3.4%, respectively. The variation was studied by ANOVA, which showed a significant difference (p = 0.000) for both of Mn and Fe concentrations at all sampling stations. In those ranges, Fe concentration was higher compared to Mn. It is believed that dissolving and diluting process influenced the concentration of Mn in the water column and sediment. Fe showed a significant correlation (r > 0.5, p < 0.01) with Mn at all stations except SR 03, indicating the natural occurrence of Mn and Fe in the water column. Meanwhile, Müller classification proved that sediment cores taken at 8 stations along Sarawak and Sabah coastal waters were not polluted with Fe and Mn with geoaccumulation index, Igeo < 1 and classification 0 – 1.
    Keywords: Fe; Mn; Müller classification; organic carbon; particle size; sediment core
  17. Fulltext Good oral health, adequate nutrient consumption and family support are associated with a reduced risk of being underweight amongst older Malaysian residents of publicly funded shelter homes
    Visvanathan R, Ahmad Z
    Asia Pac J Clin Nutr, 2006;15(3):400-5.
    PMID: 16837433
    A low body mass index in older people has been associated with increased mortality. The main objective of this study was to identify factors associated with low body mass indices [ BMIs] (< 18.5 kg/m2) in older residents of shelter care facilities in Peninsular Malaysia. 1081 elderly people (59% M) over the age of 60 years were surveyed using questionnaires determining baseline demographics, nutritional and cognitive status, physical function and psychological well being. Body mass index was also determined. Subjects were recruited from publicly funded shelter homes in Peninsular Malaysia. 14.3% of residents had BMIs < 18.5 kg/m2. Multivariate analyses (adjusted for age and sex) revealed that having no family (RR 1.98[95%CI 1.40-2.82], p<0.001) and negative responses to statement 3 [I eat few fruits or vegetables or milk products] (RR 0.62 [95% CI 0.42-0.90]; P= 0.013) and statement 5 [I have tooth or mouth problems that make it hard for me to eat] (RR 0.69 [95%CI 0.50-0.96]; P= 0.023) of the ' Determine Your Nutritional Health Checklist' were independently associated with low BMIs (<18.5 kg/m2). Older people with no family support were at risk of becoming underweight. Older people who consumed fruits, vegetables or milk or had good oral health were less likely to be underweight. Nutrient intake, oral health and social support were important in ensuring healthy body weight in older Malaysians.
  18. Functional properties of chitosan built nanohydrogel with enhanced glucose-sensitivity
    Ullah F, Othman MB, Javed F, Ahmad Z, Akil HM, Rasib SZ
    Int J Biol Macromol, 2016 Feb;83:376-84.
    PMID: 26597568 DOI: 10.1016/j.ijbiomac.2015.11.040
    A new approach to design multifunctional chitosan based nanohydrogel with enhanced glucose sensitivity, stability, drug loading and release profile are reported. Two approaches were followed for functionalization of chitosan based nanohydrogel with 3-APBA via EDC and 3-APTES. The effective functionalization, structure and morphology of Chitosan based IPN respectively were confirmed by FTIR, SEM and AFM. At physiological conditions, the glucose-induced volume phase transition and release profile of the model drug Alizarin Red with 1,2-diol structure (comparative to insulin as a drug as well as a dye for bio separation) were studied at various glucose concentrations, pH and ionic strengths. The results suggested a new concept for diabetes treatment and diols sensitivity in view of their potential hi-tech applications in self-regulated on-off response to the treatment (drug delivery and bio separation concurrently).
  19. Classification, processing and application of hydrogels: A review
    Ullah F, Othman MB, Javed F, Ahmad Z, Md Akil H
    Mater Sci Eng C Mater Biol Appl, 2015 Dec 1;57:414-33.
    PMID: 26354282 DOI: 10.1016/j.msec.2015.07.053
    This article aims to review the literature concerning the choice of selectivity for hydrogels based on classification, application and processing. Super porous hydrogels (SPHs) and superabsorbent polymers (SAPs) represent an innovative category of recent generation highlighted as an ideal mould system for the study of solution-dependent phenomena. Hydrogels, also termed as smart and/or hungry networks, are currently subject of considerable scientific research due to their potential in hi-tech applications in the biomedical, pharmaceutical, biotechnology, bioseparation, biosensor, agriculture, oil recovery and cosmetics fields. Smart hydrogels display a significant physiochemical change in response to small changes in the surroundings. However, such changes are reversible; therefore, the hydrogels are capable of returning to its initial state after a reaction as soon as the trigger is removed.
  20. Synthesis and functionalization of chitosan built hydrogel with induced hydrophilicity for extended release of sparingly soluble drugs
    Ullah F, Javed F, Othman MBH, Khan A, Gul R, Ahmad Z, et al.
    J Biomater Sci Polym Ed, 2018 03;29(4):376-396.
    PMID: 29285989 DOI: 10.1080/09205063.2017.1421347
    Addressing the functional biomaterials as next-generation therapeutics, chitosan and alginic acid were copolymerized in the form of chemically crosslinked interpenetrating networks (IPNs). The native hydrogel was functionalized via carbodiimide (EDC), catalyzed coupling of soft ligand (1,2-Ethylenediamine) and hard ligand (4-aminophenol) to replace -OH groups in alginic acid units for extended hydrogel- interfaces with the aqueous and sparingly soluble drug solutions. The chemical structure, Lower solution critical temperature (LCST ≈ 37.88 °C), particle size (Zh,app ≈ 150-200 nm), grain size (160-360 nm), surface roughness (85-250 nm), conductivity (37-74 mv) and zeta potential (16-32 mv) of native and functionalized hydrogel were investigated by using FT-IR, solid state-13C-NMR, TGA, DSC, FESEM, AFM and dynamic light scattering (DLS) measurements. The effective swelling, drug loading (47-78%) and drug release (53-86%) profiles were adjusted based on selective functionalization of hydrophobic IPNs due to electrostatic complexation and extended interactions of hydrophilic ligands with the aqueous and drug solutions. Drug release from the hydrogel matrices with diffusion coefficient n ≈ 0.7 was established by Non- Fickian diffusion mechanism. In vitro degradation trials of the hydrogel with a 20% loss of wet mass in simulated gastric fluid (SGF) and 38% loss of wet mass in simulated intestinal fluid (SIF), were investigated for 400 h through bulk erosion. Consequently, a slower rate of drug loading and release was observed for native hydrogel, due to stronger H-bonding, interlocking and entanglement within the IPNs, which was finely tuned and extended by the induced hydrophilic and functional ligands. In the light of induced hydrophilicity, such functional hydrogel could be highly attractive for extended release of sparingly soluble drugs.
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