Displaying publications 161 - 180 of 264 in total

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  1. Khodaei A, Moradi F, Oresegun A, Zubair HT, Bradley DA, Ibrahim SA, et al.
    Biomed Phys Eng Express, 2024 Aug 28;10(5).
    PMID: 39142303 DOI: 10.1088/2057-1976/ad6f14
    Radiation therapy plays a pivotal role in modern cancer treatment, demanding precise and accurate dose delivery to tumor sites while minimizing harm to surrounding healthy tissues. Monte Carlo simulations have emerged as indispensable tools for achieving this precision, offering detailed insights into radiation transport and interaction at the subatomic level. As the use of scintillation and luminescence dosimetry becomes increasingly prevalent in radiation therapy, there arises a need for validated Monte Carlo tools tailored to optical photon transport applications. In this paper, an evaluation process of the TOPAS (TOol for PArticle Simulation) Monte Carlo tool for Cerenkov light generation, optical photon transport and radioluminescence based dosimetry is presented. Three distinct sources of validation data are utilized: one from a published set of experimental results and two others from simulations performed with the Geant4 code. The methodology employed for evaluation includes the selection of benchmark experiments, making use of opt3 and opt4 Geant4 physics models and simulation setup, with observed slight discrepancies within the calculation uncertainties. Additionally, the complexities and challenges associated with modeling optical photons generation through luminescence or Cerenkov radiation and their transport are discussed. The results of our evaluation suggests that TOPAS can be used to reliably predict Cerenkov generation, luminescence phenomenon and the behavior of optical photons in common dosimetry scenarios.
  2. Kwan LL, Abdul Rashid AM, Md Noh MSF, Hoo FK, Inche Mat LN
    Cureus, 2024 Nov;16(11):e73242.
    PMID: 39650868 DOI: 10.7759/cureus.73242
    Moyamoya syndrome (MMS) is characterized by progressive narrowing of intracranial arteries and the development of collateral vessel networks, often presenting with recurrent ischemic or hemorrhagic strokes. MMS poses significant challenges in diagnosis due to its overlapping symptoms with other cerebrovascular conditions. Treatment aims to improve cerebral blood flow, reduce symptom frequency, and prevent future strokes. Management requires a multidisciplinary approach, including medical optimization and potential surgical intervention. This case report discusses a 37-year-old woman with poorly controlled type 2 diabetes and hyperlipidemia who experienced multiple strokes before being diagnosed with MMS. Initial symptoms included intermittent headaches, hemiparesis, and slurred speech. The presence of underlying metabolic conditions led to an initial assumption of atherosclerosis as the primary cause of her strokes. This case underscores the diagnostic challenge of distinguishing MMS from more common vascular conditions, highlighting the need for careful evaluation when typical risk factors like atherosclerosis do not fully explain recurrent cerebrovascular events.
  3. Mohammad Razali A, Sobri MJ, Fuad MKA, Abdul Rashid AM, Md Noh MSF
    Cureus, 2024 Nov;16(11):e73670.
    PMID: 39677153 DOI: 10.7759/cureus.73670
    A carotid-cavernous fistula (CCF) involves an abnormal communication between the carotid artery and the cavernous sinus. For indirect CCF, it usually occurs in post-menopausal women. Contralateral symptoms for indirect CCF are rare. We report a 79-year-old lady with underlying hypertension and dyslipidemia, who had a complex indirect CCF from the right internal and right external carotid artery, draining into the left ophthalmic vein and giving rise to left ocular manifestation. Endovascular embolization was attempted but was unsuccessful. The patient subsequently developed a stroke one day post-procedure, with a favorable recovery of function.
  4. Albart SA, Yusof Khan AHK, Abdul Rashid A, Wan Zaidi WA, Looi I, Hoo FK
    Malays J Med Sci, 2024 Aug;31(4):195-212.
    PMID: 39247119 DOI: 10.21315/mjms2024.31.4.16
    BACKGROUND: The Stroke e-Learning Module (SEM) is a nationwide initiative to improve stroke care in Malaysia. This study aimed to assess the module's effectiveness in improving knowledge on acute ischaemic stroke (AIS) management among Malaysian doctors.

    METHODS: This was a pre-post study design. Medical officers, specialists and general practitioners from various disciplines who work in healthcare facilities in Malaysia were recruited virtually from those who registered for the SEM on the Docquity platform between 1 February 2021 and 31 January 2022. The Acute Stroke Management Questionnaire (ASMaQ), an existing validated questionnaire, was used to measure the doctors' knowledge of AIS management before and after the SEM. The ASMaQ had three domains: i) general stroke knowledge (GSK), ii) hyperacute stroke management (HSM) and iii) advanced stroke management (ASM). The paired t- and the McNemar-tests were used to evaluate the effectiveness of the module.

    RESULTS: One hundred and seventy-one participants voluntarily responded to the pre- and post-module questionnaires. The paired t-test revealed statistically significant improvement for the ASM knowledge scores (mean difference = 2.5; 95% CI: 1.8, 3.2; P < 0.001). The baseline proportion of participants with good knowledge of GSK, HSM and ASM were 92.4%, 64.9%, and 76%, respectively. The McNemar test showed that approximately 14% of the participants had significant improvement in ASM knowledge (P < 0.001). However, no significant changes were noted for GSK (-0.6%) and HSM (4.1%).

    CONCLUSION: The SEM has been shown to increase Malaysian doctors' knowledge on ASM. However, greater effort should be made to improve GSK and HSM knowledge, particularly in areas related to stroke thrombolysis.

  5. Begum M, Rahman AK, Abdul-Rashid HA, Yusoff Z, Begum M, Mat-Sharif KA, et al.
    Appl Radiat Isot, 2015 Jun;100:79-83.
    PMID: 25468288 DOI: 10.1016/j.apradiso.2014.10.025
    Important thermoluminescence (TL) properties of five (5) different core sizes Ge-doped optical fibers have been studied to develop new TL material with better response. These are drawn from same preform applying different speed and tension during drawing phase to produce Ge-doped optical fibers with five (5) different core sizes. The results of the investigations are also compared with most commonly used standard TLD-100 chips (LiF:Mg,Ti) and commercial multimode Ge-doped optical fiber (Yangtze Optical Fiber, China). Scanning Electron Microscope (SEM) and EDX analysis of the fibers are also performed to map Ge distribution across the deposited region. Standard Gamma radiation source in Secondary Standard Dosimetry Lab (SSDL) was used for irradiation covering dose range from 1Gy to 10Gy. The essential dosimetric parameters that have been studied are TL linearity, reproducibility and fading. Prior to irradiation all samples ∼0.5cm length are annealed at temperature of 400°C for 1h period to standardize their sensitivities and background. Standard TLD-100 chips are also annealed for 1h at 400°C and subsequently 2h at 100°C to yield the highest sensitivity. TL responses of these fibers show linearity over a wide gamma radiation dose that is an important property for radiation dosimetry. Among all fibers used in this study, 100μm core diameter fiber provides highest response that is 2.6 times than that of smallest core (20μm core) optical fiber. These fiber-samples demonstrate better response than commercial multi-mode optical fiber and also provide low degree of fading about 20% over a period of fifteen days for gamma radiation. Effective atomic number (Zeff) is found in the range (13.25-13.69) which is higher than soft tissue (7.5) however within the range of human-bone (11.6-13.8). All the fibers can also be re-used several times as a detector after annealing. TL properties of the Ge-doped optical fibers indicate promising applications in ionizing radiation dosimetry.
  6. Alawiah A, Alina MS, Bauk S, Abdul-Rashid HA, Gieszczyk W, Noramaliza MN, et al.
    Appl Radiat Isot, 2015 Apr;98:80-6.
    PMID: 25644081 DOI: 10.1016/j.apradiso.2015.01.016
    The thermoluminescence (TL) glow curves and kinetics parameters of Thulium (Tm) doped silica cylindrical fibers (CF) are presented. A linear accelerator (LINAC) was used to deliver high-energy radiation of 21MeV electrons and 10MV photons. The CFs were irradiated in the dose range of 0.2-10Gy. The experimental glow curve data was reconstructed by using WinREMS. The WinGCF software was used for the kinetic parameters evaluation. The TL sensitivity of Tm-doped silica CF is about 2 times higher as compared to pure silica CF. Tm-doped silica CF seems to be more sensitive to 21MeV electrons than to 10MV photons. Surprisingly, no supralinearity was displayed and a sub-linear response of Tm-doped silica CF was observed within the analyzed dose range for both 21MeV electrons and 10MV photons. The Tm-doped silica CF glow curve consists of 5 individual glow peaks. The Ea of peak 4 and peak 5 was highly dependent on dose when irradiated with photons. We also noticed that the electron radiation (21MeV) caused a shift of glow peak by 7-13°C to the higher temperature region compared with photons radiation (10MV). Our Tm-doped fibers seem to give high TL response after 21MeV electrons, which gives around 2 times higher peak integral as compared with 10MV photon radiation. We concluded that peak 4 is the first-order kinetic peak and can be used as the main dosimetric peak of Tm-doped silica CF.
  7. Diong SH, Mohd Yusoff NS, Sim MS, Raja Aziddin RE, Chik Z, Rajan P, et al.
    J Anal Toxicol, 2014 Nov-Dec;38(9):660-6.
    PMID: 25106416 DOI: 10.1093/jat/bku096
    Gas chromatography-mass spectrometry quantitative method was developed to monitor concentrations of methadone and its metabolite 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) in plasma and urine of patients. The developed method was simple, accurate and reproducible to quantify methadone and EDDP in plasma and urine samples in the concentration range of 15-1,000 and 50-2,000 ng/mL, respectively. The proposed analytical method was applied to plasma and urine samples obtained from 96 patients undergoing methadone maintenance treatment (MMT) with daily methadone doses of 2-120 mg/day. Urinary methadone excretion was observed to be significantly affected by pH, in which the ratio of methadone to EDDP was two times higher in acidic urine (P = 0.029). The findings of this study further enhance the guidelines for monitoring of methadone treatment among outpatients. Methadone-to-EDDP ratio in urine was found to be consistent at 24 and 4 h, hence suggesting the possibility that outpatients may be monitored with single urine sample in order to check for compliance. This study which provides data on peak concentrations of methadone and EDDP as well as the ratio of both compounds has added to the body of knowledge regarding pharmacokinetic properties of methadone among heroin-dependent patients under MMT.
    Study site: University Malaya Medical Centre (UMMC), HKL, University Malaya Centre for Addiction Sciences (UMCAS) and Rehabilitation Centre of Al-Rahman Mosque, Kuala Lumpur, Malaysia
  8. Saini SM, Hamid SA, Abdul Rashid SN, Bahari N, Fakhrizzaki AA, Abu Hassan H, et al.
    Med J Malaysia, 2013 Aug;68(4):356-7.
    PMID: 24145267 MyJurnal
  9. bte Abdul Rashid NH, Yunus MR, bte Baki MM, bte Ami M, Athar PP
    J Pak Med Assoc, 2012 May;62(5):466-9.
    PMID: 22755311
    To determine the frequency of stomal recurrence in patients following total laryngectomy in our center and to compare the frequency of previously reported risk factors such as preoperative tracheostomy, subglottic invasion and the level of lymph node metastases, with the rest of the world.
  10. Zailan N, Abdul Rashid AH, Das S, Abdul Mokti NA, Hassan Basri J, Teoh SL, et al.
    Clin Ter, 2010;161(6):515-21.
    PMID: 21181079
    Chlorella vulgaris (CV) is a green microalgae enriched with nutrients, vitamins, minerals and chlorophyll. The aim of our study was to evaluate the potential wound healing effects of CV as a dressing while comparing it to sodium alginate dressing.
  11. Periayah MH, Halim AS, Mat Saad AZ, Yaacob NS, Hussein AR, Abdul Karim F, et al.
    Thromb Res, 2015 Sep;136(3):625-33.
    PMID: 26254703 DOI: 10.1016/j.thromres.2015.07.027
    Von Willebrand disease (vWD) is the second least common hemostatic disorder in Malaysia, and it has a low prevalence. This study examined the underlying platelet thrombogenicity cascades in the presence of different formulations of chitosan-derivatives in vWD patients. This paper aimed to determine the significant influence of chitosan biomaterial in stimulating the platelet thrombogenicity cascades that involve the von Willebrand factor, Factor 8, Thromboxane A2, P2Y12 and Glycoprotein IIb/IIIa in vWD.
  12. Bradley DA, Zubair HT, Oresegun A, Louay GT, Ariffin A, Khandaker MU, et al.
    Appl Radiat Isot, 2018 Nov;141:176-181.
    PMID: 29673719 DOI: 10.1016/j.apradiso.2018.02.025
    In previous work we investigated the real-time radioluminescence (RL) yield of Ge-doped silica fibres and Al2O3 nanodot media, sensing electron- and x-ray energies and intensities at values familiarly obtained in external beam radiotherapy. The observation of an appreciable low-dose sensitivity has given rise to the realisation that there is strong potential for use of RL dosimetry in diagnostic radiology. Herein use has been made of P-doped silica optical fibre, 2 mm diameter, also including a 271 µm cylindrical doped core. With developing needs for versatile x-ray imaging dosimetry, preliminary investigations have been made covering the range of diagnostic x-ray tube potentials 30 kVp to 120 kVp, demonstrating linearity of RL with kVp as well as in terms of the current-time (mAs) product. RL yields also accord with the inverse-square law. Given typical radiographic-examination exposure durations from tens- to a few hundred milliseconds, particular value is found in the ability to record the influence of x-ray generator performance on the growth and decay of beam intensity, from initiation to termination.
  13. Chainchel Singh MK, Abdul Rashid SN, Abdul Hamid S, Mahmood MS, Feng SS, Mohd Nawawi H, et al.
    Forensic Sci Int, 2020 Mar;308:110171.
    PMID: 32032870 DOI: 10.1016/j.forsciint.2020.110171
    BACKGROUND: Post-mortem Computed Tomography (PMCT) allows non-invasive or minimally invasive detection of findings that may or may not be visible during conventional autopsy, however, it does not allow the investigator to draw any conclusions regarding patency of the vessel's lumen. To address this deficiency, Post-mortem Computed Tomography Angiography (PMCTA) utilizing different contrast media and techniques have been introduced with various studies looking at the correlation between PMCTA, autopsy (gross) findings and coronary artery histology in diagnosing coronary artery disease.

    OBJECTIVES: The aim of this study is to investigate the sensitivity and specificity of PMCTA in diagnosing coronary artery stenosis using water-based contrast media introduced though the vessels of the neck, compared to the gold standard of diagnosis i.e. gross and histological evaluation of the coronary artery.

    METHOD: This was a cross sectional study of 158 arterial sections involving 37 subjects recruited from the National Institute of Forensic Medicine (IPFN), Hospital Kuala Lumpur (HKL). An unenhanced PMCT was performed followed by PMCTA using water-based contrast media introduced though the vessels of the neck. Coronary artery stenosis was determined using multiplanar reconstructionD while the degree of stenosis was determined by calculating the percentage of luminal diameter divided by the diameter of the vessel internal elastic.

    RESULTS: The analysis of PMCTA and histopathology examinations revealed a sensitivity of 61.5%, specificity of 91.7%; positive predictive value (PPV) of 40.0% and negative predictive value (NPV) of 96.4%.

    CONCLUSION: PMCTA utilizing water-based contrast introduced though the vessels of the neck yielded similar results as other methods and techniques of PMCTA. We would therefore conclude that PMCTA utilizing this technique could be used to assess the degree of calcification and the presence of significant stenosis.

  14. Begum M, Rahman AKMM, Abdul-Rashid HA, Yusoff Z, Mat Nawi SN, Khandaker MU, et al.
    Appl Radiat Isot, 2021 Aug;174:109771.
    PMID: 34048992 DOI: 10.1016/j.apradiso.2021.109771
    Present study concerns the key thermoluminescence (TL) properties of photonic crystal fibres (PCFs), seeking development of alternatively structured TL materials that are able to offer a advantages over existing passive dosimeters. In terms of their internal structure and light guiding properties the PCFs, collapsed and structured, differ significantly from that of conventional optical fibres. To investigate the dosimetric parameters of the PCFs use was made of a linear accelerator producing a 6 MV photon beam, delivering doses ranging from 0.5 Gy to 8 Gy. The parameters studied included TL response, linearity index, glow curves, relative sensitivity and TL signal fading, the results being compared against those obtained using TLD-100 chips. At 4 Gy photon dose the Ge-doped collapsed PCFs were found to provide a response 27 × that of structured PCF, also giving a TL yield similar to that of standard TLD-100 chips. Over post-irradiation periods of 15 and 30 days collapsed PCF TL signal fading were 8% and 17% respectively, with corresponding values of 37% and 64% for the structured PCF. Trapping parameters including the order of kinetics (b), activation energy (E) and frequency factor (s-1) were assessed with Chen's peak shape method. Lifetime of trapping centre was found to be (2.36 E+03) s and (9.03 E +01) s regarding the collapsed and structured PCF respectively with 6 Gy of photon beam. For the Ge-doped collapsed PCF, the high TL yield, sensitivity and low fading provide the basis of a highly promising system of TLD for radiotherapy applications.
  15. Albart SA, Yusof Khan AHK, Abdul Rashid A, Wan Zaidi WA, Bidin MZ, Looi I, et al.
    PeerJ, 2022;10:e13310.
    PMID: 35469195 DOI: 10.7717/peerj.13310
    BACKGROUND: Despite rapid advances in acute ischaemic stroke (AIS) management, many healthcare professionals (HCPs) might not be aware of the latest recommended management of AIS patients. Therefore, we aimed to determine the level and factors associated with AIS management knowledge among Malaysian HCPs.

    METHODS: This cross-sectional online questionnaire study was conducted nationwide among 627 HCPs in Malaysia using the Acute Stroke Management Questionnaire (ASMaQ). Multiple logistic regression was used to predict the relationship between the independent variables (age, gender, years of service, profession, work setting, work sector, seeing stroke patients in daily practice, and working with specialists) and the outcome variable (good vs poor knowledge).

    RESULTS: Approximately 76% (95% CI [73-79%]) of HCPs had good overall knowledge of stroke. The highest proportion of HCPs with good knowledge was noted for General Stroke Knowledge (GSK) [88.5% (95% CI [86-91%])], followed by Advanced Stroke Management (ASM) [61.2% (95% CI [57-65%])] and Hyperacute Stroke Management (HSM) [58.1% (95% CI [54-62%])]. The odds of having poor knowledge of stroke were significantly higher among non-doctor HCPs [adjusted OR = 3.46 (95% CI [1.49-8.03]), P = 0.004]; among those not seeing stroke patients in daily practice [adjusted OR = 2.67 (95% CI [1.73-4.10]), P < 0.001]; and among those working without specialists [adjusted OR = 2.41 (95% CI [1.38-4.18]), P = 0.002].

    CONCLUSIONS: Stroke education should be prioritised for HCPs with limited experience and guidance. All HCPs need to be up-to-date on the latest AIS management and be able to make a prompt referral to an appropriate facility. Therefore, more stroke patients will benefit from advanced stroke care.

  16. Abdul Rashid FNA, Bacho MZ, Hamali MA, Slawin AMZ, Mohammat MF, Shamsujunaidi R, et al.
    IUCrdata, 2023 Feb;8(Pt 2):x230075.
    PMID: 36911075 DOI: 10.1107/S2414314623000755
    The asymmetric unit of the title compound, C9H15NO4, consists of a functionalized pyrrolidine ring having an envelope conformation, synthesized as an ethyl ester. The mol-ecule has three chiral centres and crystallized as a racemic mixture. In the crystal, mol-ecules are linked by pairwise O-H⋯O bonds, generating dimers with twofold rotational symmetry.
  17. Zakaria SM, Abdullah N, Md Akhir N, Amin AS, Mohd Shukry ANA, Abdul Rashid MR, et al.
    Int J Environ Res Public Health, 2022 Sep 27;19(19).
    PMID: 36231521 DOI: 10.3390/ijerph191912219
    During the pandemic, the lives of B40 single mothers were severely affected, especially in terms of social, economic, and psychological factors. The reduction of income caused by the crisis has forced single mothers and their children to live frugally and without luxury. They also had to perform more than one job at a time during the pandemic to meet their children's needs. A qualitative study has been conducted to explore the perceptions of quality of life during the pandemic among B40 single mothers. Respondents were selected based on demographic characteristics established before the study. A focus group discussion has been conducted on ten (10) B40 single mothers in Balik Pulau, Penang. Single mothers were selected based on purposive sampling. They had to meet the inclusive criteria required to participate in the study, specifically: aged between 20 and 60 years old, belonged to the B40 income category, had children under 18 years old living together, and became single mothers due to divorce or death of husbands. The focused group discussion explored issues related to qualities of life during the pandemic. B40 single mothers expressed their concern about access to health facilities, security in residence, children's education, and economic stability. These areas of life quality have been significantly affected especially during Movement Control Order (MCO). In short, the quality of life of these single mothers has been significantly affected by the pandemic. Their vulnerability towards stress, anxiety, and depression have worsened due to financial issues. Besides the need for emotional and social support, this study found that these single mothers entail financial support.
  18. Sugeng DA, Yahya WJ, Ithnin AM, Abdul Rashid MA, Mohd Syahril Amri NS, Abd Kadir H, et al.
    Environ Sci Pollut Res Int, 2018 Sep;25(27):27214-27224.
    PMID: 30030755 DOI: 10.1007/s11356-018-2760-1
    The focus of this work is to investigate the emission characteristics of a stationary diesel engine while utilizing an emulsion fuel from a novel preparation process. The emulsion preparation was performed in real time without using any surfactant. Instead of mechanically breaking the water down into droplets, the water is delivered thermally, by changing its phase from gas to liquid. Steam is used in this proposed process, where it will be converted into suspended water droplets once it meets colder diesel. The product is called steam-generated water-in-diesel emulsion fuel (S/D). The method is expected to reduce the moving components of a previous surfactant-less system; therefore, reducing costs and increasing the system reliability. The emission characteristics of S/D were compared with EURO 2 diesel (D2), and a conventional emulsion denoted as E10. E10 was prepared using 10% water (volumetric) and SPAN80 as a surfactant. The emission characterizations were carried out based on the exhaust gas of a single cylinder naturally aspirated CI engine fueled with D2, S/D, and E10. Compared to D2, both emulsions significantly reduced the emissions of nitrogen oxides (NOx) (E10 max ↓58.0%, S/D max ↓40.0%) and particulate matter (PM) (E10 max ↓20.0%, S/D max ↓57.0%).
  19. Abdul Rashid MR, Syed Mohamad SN, Tajjudin AIA, Roslan N, Jaffar A, Mohideen FBS, et al.
    PMID: 36901486 DOI: 10.3390/ijerph20054476
    This study aimed to explore the socio-demographic characteristics, mental health status, and perceived causes of pandemic fatigue with COVID-19 pandemic fatigue among the general population of Malaysia. The data was collected online during the transition from the COVID-19 pandemic phase to the endemic phase in Malaysia from 1 to 30 April 2022. Sociodemographic data, Depression Anxiety Stress Scale-21 (DASS-21), perceived causes of pandemic fatigue, and the Fatigue Assessment Scale (FAS) were included in the survey. The chi-square test and a simple logistic regression analysis were used to identify predictors of pandemic fatigue. The completed survey (N = 775) included individuals aged 18 years or above [mean 31.98 (SD = 12.16)] from all states in Malaysia. Pandemic fatigue prevalence was 54.2%. Severe to extremely severe depression, anxiety, and stress symptoms were detected in 11.2%, 14.9%, and 9.1% of the participants, respectively. Younger age, non-Malay ethnicity, living alone, and higher income categories were significantly higher in the fatigued group. Higher DASS-21 scores on all domains were associated with higher FAS scores. Meanwhile, high scores for perceived tiredness from complying with the COVID-19 Standard Operating Procedure (SOP), perceived risk of infection from COVID-19, perceived hardship due to the pandemic, perceived public complacency during the pandemic, and perceived changes due to the pandemic were associated with a higher FAS score. This study provides valuable information for policymakers and mental health professionals worldwide on pandemic fatigue and its associated factors, including mental health status in Malaysia.
  20. Jori Roslan N, Jamal SH, Abdul Rashid JI, Norrrahim MNF, Ong KK, Wan Yunus WMZ
    Heliyon, 2024 Feb 29;10(4):e25993.
    PMID: 38380021 DOI: 10.1016/j.heliyon.2024.e25993
    Nitrocellulose (NC) has garnered significant interest among researchers due to its versatile applications, contingent upon the degree of nitration that modifies the cellulose structure. For instance, NC with a high nitrogen content, exceeding 12.5%, finds utility as a key ingredient in propellant formulations, while variants with lower nitrogen content prove suitable for a range of other applications, including the formulation of printing inks, varnishes, and coatings. This communication aims to present the outcomes of our efforts to optimize the nitration reaction of bacterial cellulose to produce high-nitrogen-content NC, employing the response surface methodology (RSM). Our investigation delves into the influence of the mole ratio of sulfuric and nitric acids, reaction temperature, and nitration duration on the nitrogen content of the resultant products. Utilizing a central composite design (CCD), we identified the optimal conditions for NC synthesis. Analysis of variance (ANOVA) underscored the substantial impact of these reaction conditions on the percentage of nitrogen content (%N) yield. By implementing the predicted optimal conditions-namely, a H2SO4:HNO3 mole ratio of 3:1, a reaction temperature of 35 °C, and a reaction period of 22 min-we successfully produced NC with a nitrogen content of 12.64%. Characterization of these products encompassed elemental analysis, Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermal gravimetric analysis (TGA), and field emission scanning electron microscopy (FESEM).
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