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Fractional factorial design-based evaluation of physicochemical parameters affecting biodiesel properties from Chlorella sp. PG96
(Elsevier BV, 2026-01)
Roya Parichehreh
;
Reza Gheshlaghi
;
Mahmood Akhavan Mahdavi
;
Hesam Kamyab
Biodiesel, as a renewable energy source synthesized through the transesterification of algal lipids, has received increasing attention in recent years. The quality of biodiesel derived from microalgal lipids depends largely on the composition of fatty acid methyl ester in the fuel. This research employed a fractional factorial design (2 ¹¹⁻⁷) to statistically screen eleven independent factors, including NaHCO3, CO2, MgSO4.7H2O, K2HPO4, NaNO3, NH4Cl, salinity, light spectrum, aeration rate, light intensity, and temperature, for achieving a rich fatty acid profile by Chlorella sp. PG96 (a strain isolated from municipal wastewater), as well as the synthesis of superior-quality biodiesel. The effects of all eleven physicochemical factors and their interactions on the growth characteristics (biomass and lipid production) of Chlorella sp. PG96 were thoroughly investigated in our previous study. According to the experimental results of the present study, the maximum concentrations of palmitic acid (32.23 ± 2.87 %), oleic acid (31.53 ± 3.31 %), saturated fatty acids (38.07 ± 4.03 %), and monounsaturated fatty acids (33.63 ± 3.36 %) in microalgal lipids were obtained when Chlorella sp. PG96 was grown at a low NaHCO3 concentration (0 mg L⁻¹) and white light irradiation. The estimated values of biodiesel properties such as iodine value, unsaturation degree, oxidation stability, cetane number, higher heating value, density, and kinematic viscosity were all in accordance with the quality benchmarks established by ASTM and EN 14214. The findings further demonstrated that temperature and light intensity represented the key determinants influencing fatty acid composition. Aeration rate and salinity had the most significant effects on the cetane number index, whereas the oxidation stability of algal oil was markedly affected by the concentrations of NaNO₃ and NaHCO₃. Moreover, ammonium as a nitrogen source and bicarbonate as a carbon source exhibited greater significance in fatty acid biosynthesis compared with nitrate and CO₂, respectively. The interactions between NaHCO₃ and the light spectrum, as well as between NaHCO₃ and NH₄Cl, were found to be the most significant for all measured responses. It is suggested that Chlorella sp. PG96, when cultivated with elevated NH₄Cl concentration and light intensity but under reduced temperature (320 mg L⁻¹, 22,500 Lux, and 20 °C, respectively), may act as a promising feedstock for biodiesel production.
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Biomedical MXene-polymer nanocomposites: advancing photothermal therapy, antibacterial action, and smart drug delivery: a review
(Elsevier BV, 2025-06)
Ali Mohammad Amani
;
Lobat Tayebi
;
Ehsan Vafa
;
Mohammad Javad Azizli
;
Milad Abbasi
MXenes are hydrophilic, conductive, tunable, and biocompatible two-dimensional ceramic materials prepared by etching the 'A' layer from their precursor MAX phases. Although MXenes show exceptional promise in photothermal therapy, biosensing, and regenerative medicine, they face challenges such as oxidative instability in physiological environments, limited drug-loading capacity, and unpredictable immune responses. To address these limitations, MXene/polymer nanocomposites incorporating both synthetic polymers (e.g., polyethylene glycol (PEG), polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP), and polylactic-co-glycolic acid (PLGA)) and natural biopolymers (e.g., cellulose nanofiber, gelatin, chitosan, hyaluronic acid, and soybean phospholipids) have been developed. These composites enhance functionality for biomedical applications such as photothermal cancer therapy, biosensors, antibacterial agents, bone regeneration, and targeted drug delivery. The hydrophilic nature of MXenes makes them suitable for transformation into metallic-conductive electrodes, while their compatibility with metals, ceramics, and polymers improves performance in advanced applications. This review paper discusses the properties, synthesis methods, and biomedical applications of MXene/polymer nanocomposites, emphasizing the roles of both synthetic and natural biopolymers. Key achievements include near-infrared (NIR) absorption for efficient drug delivery, anticancer activity, bioimaging, and antimicrobial effects. In addition, the limitations of these nanocomposites and potential solutions are examined.
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Optical characterization of NiO nanoparticle-decorated single-walled carbon nanotubes synthesized via ultrasonic-assisted sol-gel method
(Elsevier BV, 2025-09)
Seyedeh Maryam Banihashemian
;
Hesam Kamyab
;
Shahabaldin Rezania
;
Daniel Simancas-Racines
;
Saravanan Rajendran
The decoration of carbon nanotubes with metal oxide nanoparticles has been employed to enhance their intrinsic properties and expand their applicability across various technological fields. This study investigated the functionalization of single-walled carbon nanotubes (SWCNTs) by treating them with a 3:2 mixture of sulfuric acid and nitric acid, which introduces oxygen-containing functional groups to enhance their dispersibility and reactivity. Nickel oxide nanoparticles (NiONPs) were synthesized and integrated onto the functionalized SWCNTs using an ultrasonic-assisted sol-gel technique, allowing uniform distribution. Then, the NiONP/SWCNT composite was evaluated for thermal stability and elemental composition via thermogravimetric analysis (TGA) and energy-dispersive X-ray spectroscopy. Both field emission scanning electron microscopy and high-resolution transmission electron microscopy confirmed the successful decoration of NiONPs (particle size <20 nm, mean value of 7.87 ± 3.02 nm) on the SWCNTs. Fourier-transform infrared spectroscopy revealed characteristic peaks corresponding to NiO at 644 cm−1 as IR-active modes induced by NiO–SWCNT and Raman spectroscopy further verified the chemical bonding between NiONPs and SWCNTs. This shows shifts in the radial breathing mode and G bands of SWCNTs, indicative of strong interfacial chemical interactions. Optical analysis demonstrated that the NiO-SWCNT nanocomposite exhibited a reduced band gap compared to pure NiO nanoparticles but a broader band gap than intermediate-phase SWCNT configurations. In addition, UV–Vis spectroscopy identified a prominent absorption peak within the 600–800 nm wavelength range, aligning with the near-infrared (NIR) spectral region. This enhanced NIR absorption suggests improved light-capturing efficiency, which could significantly benefit applications in photocatalysis and optoelectronics.
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Photocatalytic CO2 conversions on copper nanoparticles investigated by Raman spectral changes using convolutional neural networks
(Elsevier BV, 2025-10)
Heung Seok Lee
;
Jaerin Choi
;
Jin Yong Lee
;
Ji Eun An
;
Thi Huong Vu
A convolutional neural network (CNN) deep learning process is employed to analyze in situ Raman scattering data for CO2 capture and its photocatalytic conversions onto copper sulfide hollow nanospheres (CuSHNSs) and copper nanocubes (CuNCs) in microalgae solution of Spirulina maxima. Raman spectra under visible light at 633 nm in a microfluidic solution provided representative vibrational marker bands of Cdouble bondO features at ∼2100 cm−1 and CH2/CH3 bending vibrations at ∼1400 cm−1 that are correlated with CO2 reduction products of carbon monoxide (C1) and multi‑carbon species such as propanol (C3), butanol (C4), respectively. Accumulated Raman spectra were trained and analyzed to estimate photocatalytic pathways using CNN algorithm. The presence of Spirulina maxima microalgae on the alteration of photocatalytic processes is studied by analyzing collective Raman spectral changes. The main observation is that strong CO peaks in Raman spectra of CO2 adsorbed by CuNCs almost disappeared after treatment with microalgae, whereas their intensities were slightly increased in case of CuSHNS. The CNN deep learning process for Raman spectra was effective to differentiate photocatalytic mechanisms of CO2 conversion onto nanoparticle surfaces.
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Application of ZnCl2-modified Biowaste to the removal of highly polluted dye: A case study of investigating the kinetics and adsorption isotherms
(Elsevier BV, 2025-09-01)
Lekaa Hussein Abid
;
Zainab Haider Mussa
;
Fouad Fadhil Al Qaim
;
Hesam Kamyab
;
Haider Falih Shamikh Al-Saedi
The purpose of this study is to generate ZnCl2-modified walnut shell activated carbon (ZnCl2-WSAC) for the removal of methylene blue (MB) from an aqueous solution by evaluating the adsorption capabilities of raw walnut shell powder following treatment with zinc chloride. To do this, the ZnCl2-WSAC’s mass (0.04–0.12 g), the starting MB concentration (50, 80, and 100 mg/L), pH solution (2–10), the contact period (0–180 min), and the temperature (20–50 °C) were selected as the effective parameters. The ZnCl₂-WSAC was characterized using various analytical techniques, including identification based on its diffraction pattern, examination of morphological features and surface characteristics before and after methylene blue treatment, and assessment of malachite green adsorption on the fig leaf carbon. The results demonstrated high removal percentages and excellent adsorption efficiency In the present study, two common models, Langmuir and the Freundlich models, were used to examine the experimental isotherm data after the adsorption of MB dye. The highest adsorption capacity was 35.4 mg/g. After analyzing the experimental kinetic data, it was determined that the pseudo-second-order model, which had an excellent determination coefficient (R2 = 0.9989), was better suited to describe the adsorption process. By using the Van't Hoff equation to compute the exchanged standard enthalpy (∆H° = 26.3279 KJ/mol), the adsorption process was exothermic. The adsorption process of the MB dye on ZnCl₂-WSAC exhibited spontaneous behavior at different temperatures, in which standard Gibbs free energy values (∆G°) ranged from -2.348 to -5.284 KJ/mol. It was determined that ZnCl2-WSAC might be used as a new, efficient, and reasonably priced adsorbent to remove the dye from solution.
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Fungal biopolymer-based nanoparticles for wound healing: Mechanisms, applications, and future perspectives
(Elsevier BV, 2025-12-01)
Kaakarlu Shivakumar Vinanthi Rajalakshmi
;
Balamuralikrishnan Balasubramanian
;
Hemanth Hinnakki
;
Arun Meyyazhagan
;
Wen-Chao Liu
Fungal derived biopolymers have emerged as a promising alternative to the existing synthetic materials and have gained heightened interest in wound healing platforms due to their unique properties, such as durability, biodegradability, biocompatibility, low-toxicity, non-immunogenicity, and analogy to the native extracellular matrix. Major fungal biopolymers such as chitin, chitosan, β-glucan, mannan, and pullulans offer several biomedical and clinical advantages in wound healing to remodel the injured tissue, making them suitable for accelerating the various phases of wound healing. These biopolymers not only support cell proliferation, angiogenesis, and tissue remodelling but also serve as effective carriers for controlled drug delivery, enhancing the efficacy of therapeutic agents to accelerate the cellular responses at the wound site. The review also outlines the biological processes involved in various phases of wound healing to provide insight into future explorations in developing optimized wound dressings that ensure maximal reduction of inflammation and allow skin to remodulate. Fungal-mediated nanoparticles and hybrid nanocomposites have further improved the functional performance of wound dressings by providing increased mechanical stability, biocompatibility, and targeted bioactivity. Collectively, these findings highlight the significant role of fungal biopolymer-based nanoparticles as a novel, sustainable, and effective regime for advanced wound management.
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Investigating the optimal replacement percentage of various types of coal waste with chemical additives in concrete construction for sustainable energy applications
(Elsevier BV, 2025-09)
Mahdi Shariati
;
Mehdi Tazikeh
;
Morteza Naghipour
;
Bagher Hoseinian
;
Hesam Kamyab
The large coal production and consumption has caused environmental problems worldwide as a source of energy production with irreparable effects on soil, water, and the ecosystem. In addition, producing coal waste in coal washing plants and burying it intensifies the issue in nature. Due to the rising generation of coal waste from various sources, this study utilized several forms of coal waste obtained from a coal-washing plant in the production of both structural concrete (with a water-cement ratio of 0.54) and non-structural concrete (with a water-cement ratio of 0.7). The impact of coal waste on compressive strength (CS) was examined at curing ages of 7, 28, and 56 days. Various percentages of coal waste were substituted for both cement and sand. A superplasticizer was incorporated into the concrete mixtures to enhance the workability and achieve the desired slump and strength levels. According to the compressive strength findings, the ideal replacement level of sand with jig coal waste was 30 %. For 56-day-old specimens, the optimal substitution rates for cement with jig coal waste powder, flotation coal waste, and coal waste ash were found to be 10 %, 10 %, and 20 %, respectively. Notably, adding 10 % coal waste powder and coal waste ash increased compressive strength by 22 %, 23 %, and 44 % at 56 days.
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Dielectrophoresis-based microfluidics for detection and separation of circulating tumor cells
(Elsevier BV, 2025-06-01)
Najafipour, Iman
;
Pegah Sadeh
;
Amani Ali Mohammad
;
Hesam Kamyab
;
Chelliapan, Shreeshivadasan
Circulating tumor cells (CTCs) represent a critical focus in cancer research due to their potential to enable early detection, monitor disease progression, and facilitate personalized therapies. However, existing isolation techniques often face significant limitations, including low specificity, reduced recovery rates, and the inability to preserve cellular viability for downstream applications such as genetic profiling and drug testing. This review addresses a key knowledge gap in the development of efficient, label-free, and scalable technologies for CTC isolation, emphasizing the role of dielectrophoresis (DEP)-based microfluidic systems. DEP leverages the intrinsic dielectric properties of cells to enable selective and non-invasive separation, eliminating the need for surface markers and ensuring high cell integrity. The study highlights the integration of nanomaterials, such as gold nanoparticles and graphene oxide nanosheets, as a novel approach to overcome existing challenges in DEP-based platforms. These nanomaterials improve the specificity and sensitivity of CTC capture by increasing surface area and biocompatibility. Key advancements discussed include the optimization of electrode designs, tuning of electric field parameters, and innovative system configurations that enhance recovery efficiency and separation purity. The review also compares various DEP configurations, such as electrode-based, insulator-based, and contactless systems, evaluating their unique advantages and suitability for different applications. In addition to reviewing current advancements, the paper outlines future directions for the field, emphasizing the need for large-scale clinical validation to establish DEP-based systems as reliable diagnostic tools. This review provides a comprehensive framework for advancing DEP-based microfluidic platforms, offering a transformative approach for early cancer detection, personalized medicine, and the broader application of innovative diagnostic technologies in clinical settings.
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High-performance supercapacitors based on NiMn layered double hydroxides/Ni3S2 nanocomposite
(Elsevier BV, 2025-04-01)
Yezeng He
;
Xinfeng Liu
;
Ke He
;
Hesam Kamyab
;
Lalitha Gnanasekaran
Layered double hydroxide (LDH), an emerging electroactive material, receives significant attention in storage and energy conversion area due to its excellent ion insertion and exchange capacity. Transition metal sulfides with multiple oxidation states and redox reactions maintain high-power density. In this research, NiMn-LDH on transition metal sulfides M − S (M = Ni, Co, Mn, Fe) are synthesized. Of these, NiMn-LDH/Ni3S2 demonstrates excellent electrochemical efficiency. In the three-electrode system, NiMn-LDH/Ni3S2 electrode achieves high specific capacitance of 2028.38 mF cm⁻2 at 1 mA cm⁻2 and excellent cycling stability of 69.53 % retention after 5000 cycles at 10 mA cm⁻2. The device consisting of activated carbon and NiMn-LDH/Ni3S2 exhibits a remarkable energy density of 63.06 Wh kg⁻1 at a power density of 1599.94 W kg⁻1. The NiMn-LDH/Ni3S2 electrode demonstrates an effective pseudo-capacitance performance and holds a great promise for electrodes in capacitive energy storage devices. © 2025 Elsevier B.V.
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Multifunctional MXenes nanocomposite platforms for biosensing and wearable sensor technologies
(Springer Science and Business Media LLC, 2025-02-01)
Ali Mohammad Amani
;
Hesam Kamyab
;
Ehsan Vafa
;
Alireza Jahanbin
;
Milad Abbasi
MXenes are nanostructures with unique characteristics, such as hydrophilicity, large surface area, strong metallic conductivity, strong ion transport capabilities, biocompatibility, minimal diffusion barrier, and easy functionalization, which make these compounds suitable for bioanalytical applications. These materials are formed of transition metallic nitrides, carbides, or carbonitrides. Owing to their unique properties, MXenes have gained interest in various fields, including sustainable energy generation, fuel cells, supercapacitors, electronics, and catalysis. The composition and layered structure have made MXenes particularly appealing to biosensing applications. They can be used in electrochemical biosensors because of their high conductivity and multilayered architecture, which ensure the retention of activity in immobilized biomolecules. This review highlights the application of MXenes in electrochemical and optical biosensors, identifying future requirements and potential in this sector, particularly in the development of wearable sensors and platforms with integrated biomolecule detection.

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