Browsing by Author "Dr. Sadaf Ul Hassan"

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Bioactive MXene Based Nanocomposite for Potential Application in Wound Healing
(Library Information Services, COMSATS University Islamabad, Lahore Campus., 2025-04-01) Amina Asif; CIIT/FA23-R06-002/LHR; Dr. Sadaf Ul Hassan; LHR TP 9680
MXenes, a class of two-dimensional transition metal carbides and nitrides, have emerged as promising materials in the biomedical field due to their exceptional electrical conductivity, surface functionality, and biocompatibility. Their ability to serve as active carriers and structural supports makes them ideal candidates for designing multifunctional nanocomposites. In this study, a hybrid nanocomposite comprising MXene, ZnO/Ag/Ag2O was synthesized and characterized using XRD, FTIR, SEM and UV–Vis techniques. The structural analysis confirmed the successful incorporation of metal oxide nanoparticles onto MXene sheets. The ZnO/Ag/Ag2O@MXene nanocomposite demonstrated excellent antimicrobial activity against S. aureus, E. coli, P. aeruginosa, and K. pneumoniae. Bacterial time scale analysis showed reduced absorbance over 32 hours, especially in S. aureus and E. coli, indicating strong and sustained antibacterial performance. In a full thickness wound model in mice, the treated group exhibited 97.29% wound closure by Day 10, significantly outperforming the negative control group. The composite also exhibited anti-inflammatory property in a carrageenan-induced paw edema whereby thickness of the paw reduced form 7.33 mm to 4.72 mm in 24 h, which was very similar to that of the positive control. Histology proved increased tissue restoration and decreased inflammation, re-epithelialization of wounds and collagen arrangement in treated wounds. The above observations confirm the high possibilities of the ZnO/Ag/Ag2O@MXene nanocomposite as an efficient and universal material that can be used in biomedical applications, especially infection prevention, wound healing, and inflammation treatment.
Catalytic Optimization of Lignin-Cr/Zn Binary Oxide Nano-composite for Dye Removal from Industrial Waste Water using Box-Behnken Design
(Library Information Services COMSATS University Islamabad Lahore Campus, 2023-02) Maha Shakeel; SP22-R06-017; Dr. Sadaf Ul Hassan; LHR TP 8656
The most prevalent health issues these days is the lack of access to good drinking water. One of the main substances that renders water unsafe to drink is industrial dyes. Of these dyes, organic dye methylene blue (MB) poses the greatest risk to the environment and human health because it is poisonous, non-biodegradable and carcinogenic. It is typically discharged into untreated water bodies, endangering the health of people and other living things. Therefore, the development of an efficient and environmentally friendly method for eliminating MB from effluent is imperative. A popular advanced oxidation method for removing MB is photodegradation. Absolute mineralization of the dye to simple, harmless species is one of its benefits, and it may also lower processing costs. For readers operating in the field of dye deterioration research, this review serves as a foundational instruction. A summary of MB's reaction routes, intermediate products, final products, and photodegradation method is also provided. Lignin is a prevalent, naturally occurring, non-destructive organic compound previously regarded as agricultural waste and is now considered a precious material. This paper presents the synthesis of doped lignin with chromium zinc oxide resulting in a L@CrZnO composite by co-precipitation method which showed promising results as an antibacterial agent and for photocatalytic degradation of organic pollutants specifically MB followed by characterization with various methods like UV-visible spectrophotometry, Fourier-transform infrared spectroscopy (FT-IR), x-ray diffraction spectroscopy (XRD), and scanning electron microscopy (SEM). Its antibacterial activity was determined by
Design and Development of Eco-friendly Packaging System Utilizing Lignin Based Hydrogel Coated Biodegradable Paper
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2024) Fatima Amjad; FA22-R06-017; Dr. Sadaf Ul Hassan; LHR TP 9328
A lignin based hydrogel was synthesized by physically cross-linking polyvinyl alcohol (PVA), chitosan (Ch) and lignin (Lgn) precursors. The prepared hydrogel was subjected to the cellulosic paper base as a biocoating. The interactions among the hydrogel precursors and effect of hydrogel on the crystalline behavior of hydrogel was evaluated using FTIR and XRD and the overall effect of hydrogel on the mechanical strength and barrier properties of the newly developed materials were investigated through tear index, tensile strength, puncture resistance, Cobb tests for water and oil and water contact angle measurements of uncoated and biocoated paper surfaces. The analysis of strength parameters revealed that the prepared biocoating improved the mechanical properties of the material by 40% as compared to the uncoated paper. The water contact angle analysis confirmed that the addition of lignin and chitosan to the PVA matrix sufficiently improved the hydrophobicity of paper surface resulting an improved resistance to water adsorption. The air, moisture and oil barrier properties again suggested that and an increase in the lignin concentration improved the barrier properties of the paper. The biodegradability of the prepared paper samples were investigated using compostability test. A customized soil burial test was developed and the extent of biodegradability was evaluated over a time period of 30 days. The research underscores that the prepared PVA/chitosan/lignin based biocoating has a great potential to not only provide good mechanical and barrier properties but also has a potential to replace synthetic packaging materials for sustainable and eco-friendly biobased packaging material.
Desulfurization of Model Fuel Oil Using Modified Lignin@S-g-C3N4: Optimization via Response Surface Methodology
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) Saba Iqbal; CIIT/SP24-R06-014/LHR; Dr. Sadaf Ul Hassan; LHR TP 10020
This work reports the oxidative desulfurization of dibenzothiophene in model fuel using Kraft Lignin doped S-graphitic carbon nitride (Fe@KL/S-g-C₃N₄), a newly synthesized and eco-friendly catalyst. Thus, the formation of the composite was confirmed using other characterization techniques such as Energy-Dispersive X-ray Spectroscopy (EDX), Raman Spectroscopy, UV-Visible Spectroscopy, X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). The result further showed that Kraft lignin (KL) was well adsorbed on to the S-g-C₃N₄ surface. New functional groups created through Kraft lignin adsorption increase surface coverage, add new active sites and improve S-g-C₃N₄ dispersion. The combined action inside the Fe@KL/S-g-C₃N₄ composite enhances its reactivity and also broadens the optical adsorption range. Optimizing the catalyst's effectiveness and assessing the impact of crucial variables on dibenzothiophene conversion. The following parameters were found to be ideal for maximal sulfur removal (98.37% conversion from 200 ppm): 42.5 °C, 0.3 g of catalyst, 32.5 minutes of reaction time, and 1 ml of H2O₂ as the oxidant. The quadratic model was shown to be very accurate (R2 = 0.9905), with a negligible lack of fit (p-value = 0.6671) when compared to the pure error, according to statistical analysis using ANOVA. The heterogeneous catalyst showed exceptional longevity by retaining both its structural integrity and its catalytic properties across five consecutive reuse cycles, proving to be a sustainable choice for desulfurization operations.
Desulfurization of Model Fuel with Mxene-Polyoxometalate Based Catalyst: Optimized by Box Behnken Design
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) Kanwal Shaheen; CIIT/FA23-R06-012/LHR; Dr. Sadaf Ul Hassan; LHR TP10012
Transportation fuels containing sulfur compounds are very dangerous to the environment and to health since when burnt they result in the generation of sulfur oxides. More stringent fuel regulations have necessitated the urgent need to have efficient and sustainable desulfurization technologies. The paper is concerned with the desulfurization of model fuel with an MXene-polyoxometalate (POM) based catalyst with process optimization being done by using Box-Behnken experimental design. The synthesis and characterization of a MXene-supported polyoxometalate catalyst was verified by the use of different physicochemical methods to establish the integrity of its structure, surface activity, and catalytic performance. The oxidative desulfurization of model fuel having typical sulfur compounds under mild reaction conditions was tested as catalystics. The most important operating parameters such as the dose of catalyst, oxidants to sulfur ratio, temperature of reaction, and reaction time were carefully explored. The Box Behnken design of Response Surface Methodology (RSM) was used to approximate and optimize the desulfurization reaction and reduce the amount of experimental experiments. The predicted and experimental results were found to have a strong correlation and the developed quadratic model was found to possess high significance and reliability as statistically determined. The synergistic outcome between MXene and polyoxometalate elements was observed as a great removal of sulfur rate under optimal reaction conditions. This is due to the high surface area, good electron transfer characteristics of MXene and the high oxidative ability of the polyoxometalate which have increased desulfurization performance. Also, the catalyst was well stabilized and could be used repeatedly in various cycles, which implies that it can be used practically. In general, the study indicates that the use of MXene polyoxometalate based catalysts and ix statistic optimization by Box Behnken design is a cost effective and eco-friendly method of deep desulfurization of fuels which can be useful in industrial desulfurization technology in future
Desulphurization of Fuel Oil with Tubular-Polyoxometalates based Catalyst: Optimization Using Response Surface Methodology
(Library Information Services COMSATS University Islamabad Lahore Campus, 2023-02-27) Hamna Khalid; SP22-R06-004; Dr. Sadaf Ul Hassan; LHR TP 8643
A facile catalyst termed H4SiW12O40@fHNTs was synthesized and optimized for the oxidative desulphurization of model fuel oil. Halloysite nanotubes (HNTs) were subject to functionalization with 3-aminopropyltriethoxysilane (APTES) and subsequently utilized as a substrate to immobilize H4SiW12O40. The electrostatic interaction between H4SiW12O40 and the functionalized halloysite nanotubes was characterized using UV, FTIR, XRD, and Raman spectroscopy. The oxidative desulphurization process was conducted using an oxidant i.e., hydrogen peroxide and acetonitrile as the extractant. The optimization of process variables, including reaction temperature, catalyst amount, and oxidant concentration, using the Box-Behnken method. The optimal conditions were determined to be 70°C, 70 mg, and 8 ml oxidant concentration, resulting in a desulfurization efficiency of 92.17%. Furthermore, the effectiveness of H4SiW12O40@fHNTs was demonstrated in real fuel samples, reducing dibenzothiophene content from 354 ppm to 224 ppm. The catalyst exhibited excellent recyclability, maintaining a stable desulphurization rate over five consecutive cycles. This research underscores the potential of H4SiW12O40@fHNTs as an effective and reproducible catalyst for the process of oxidative elimination of sulphur, offering promise for the development of cleaner and more sustainable fuel technologies. ix
Exploring the Potential of Mn/Zno@Mxene Nanocomposite in Biomedical Applications
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) Hina Murtaza; CIIT/SP24-R06-007/LHR; Dr. Sadaf Ul Hassan; LHR TP 10016
Mxenes are two-dimensional transition metal composed of carbides and nitrides, which have recently attracted much attention as biomedical application platforms owing to their high electrical conductivity, numerous surface functional groups, and biocompatibility, which is favorable, giving them the best places to design multifunctional nanocomposites. This paper has managed to prepare and characterize a MnZno@Mxene nanocomposite through XRD, FTIR, Raman spectroscopy, UV-Vis spectroscopy, SEM, EDX, elemental mapping, and XPS. The MnZno@Mxene nanocomposite was found to have great antibacterial activity against both Gram-positive and Gram-negative bacterial with the maximum inhibitory zone of 22 mm against Escherichia coli, 18 mm against Staphylococcus aureus, and 19 mm against Pseudomonas aeruginosa, as compared to the standard antibiotics, including gentamicin and ciprofloxacin, and time-kill kinetic analysis revealed successful and sustained bacterial inhibition, especially in E. coli. A wound-healing assessment of a full-thickness excisional wound model in vivo showed that the treated group had a significantly faster healing rat with 95.19% wound closure at 10 days as opposed to 66.76% in the negative control, as well as increased skin regeneration and improved wound morphology. In addition, the nanocomposite also showed significant anti-inflammatory effects in carrageenan induced paw edema model, with paw thickness reducing from 4.39 mm to 6.96 mm after 24 hours, as a result, a change similar to the positive control. The high potential of MnZno@Mxene was further validated by histopathological analysis, which revealed increased re- epithelialization, decreased inflammation, and ordered deposition of collagen in treated tissues, indicating high adaptability and usefulness of MnZno@Mxene as an antimicrobial therapy, wound healing, and inflammation control material.
Exploring the Potential of ZnO/Ag/Ag2O@ chitosan Nanocomposite in Antibacterial Activity, Angiogenesis and Wound Repair
(Library Information Services, COMSATS University Islamabad, Lahore Campus., 2025-04-01) Khadija Hameed; CIIT/FA23-R06-013/LHR; Dr. Sadaf Ul Hassan; LHR TP 9688
Clinical medicine continues to face significant challenges due to the advent of multidrug resistant infections and delayed wound healing, leading to the need for the creation of multifunctional biomaterials with regenerative and antimicrobial qualities. A novel ZnO/Ag/Ag2O@chitosan nanocomposite was created in this study by co-precipitation, and its antibacterial, anti-inflammatory, and wound-healing properties were assessed. Comprehensive characterization methods including FTIR, XRD, SEM, and UV-Vis indicated that a structurally stable nanocomposite with desired morphological and elemental properties had been successfully formed. Agar well diffusion and time dependent optical density measurements were used to evaluate the antibacterial potential against therapeutically relevant strains of both Gram-positive and Gram-negative bacteria. The nanocomposite demonstrated broad-spectrum antibacterial efficacy against Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumoniae, with noticeably larger zones of inhibition comparable to standard antibiotics. Studies on in vivo wound healing in a mouse excision model showed that the treatment group's wound contraction and tissue regeneration were faster than those of the positive and negative controls. Histopathological analysis showed neovascularization, re-epithelialization, and well-organized dermal architecture. The ZnO, Ag, and Ag2O synergy of the chitosan matrix enhanced tissue healing, bacterial membrane disruption, and the formation of reactive oxygen species (ROS). Due to its anti-inflammatory, antibacterial, and wound healing characteristics when combined, these findings suggest that ZnO/Ag/Ag2O@chitosan nanocomposite is a suitable candidate for biomedical purposes, particularly in the treatment of infected wounds.
Latest Approach to Fuel Desulfurization Using Polyoxometalate Catalyst Modified Halloysite Nanotubes Optimized by Surface Response Methodology
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2024) Arsheen Umer; FA22-R06-002; Dr. Sadaf Ul Hassan; LHR TP 9325
A novel catalyst termed K6P2W18O62·nH2O@fHNTs was synthesized and optimized for the photo-oxidative desulphurization of model fuel oil. Halloysite nanotubes (HNTs) were subject to functionalization with 3-aminopropyltriethoxysilane (APTES) and subsequently utilized as a substrate to immobilize K6P2W18O62·nH2O. FTIR, XRD, and SEM analysis confirm the electrostatic interaction between K6P2W18O62·nH2O and the functionalized halloysite nanotubes. Photo-oxidative desulphurization process was conducted using light as an energy source, acetonitrile as the extracting agent and H2O2 as an oxidant. The optimization of reaction variables, including reaction time (15-45 min), temperature (40-70 °C), and catalyst dosage (0.05-0.1 g) using the Box-Bhenken method. The optimal conditions were determined to be 70°C, 0.1 g, and 30 min, resulting in a desulfurization efficiency of 91.51%. The catalyst exhibited excellent recyclability, maintaining a stable desulphurization rate over seven consecutive cycles. This research highlights the potential of K6P2W18O62·nH2O@fHNTs as an effective and reproducible catalyst for the process of photo-oxidative degradation of sulfur, offering promise for the development of cleaner and more sustainable fuel technologies.