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Antibacterial characterization of ciprofloxacin-doped electrospun of low molecular weight polyethylene oxide (PEO) and sodium alginate (NaAlg) nanofibers
(2026-02-23)
Niyomchon, Phuphinee
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Treebupachatsakul, Treesukon
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Srirussamee, Kasama
Producing nanofibers using the electrospinning technique is a developed method that is widely used and of significant interest nowadays. This technique can be applied using various types of polymers. This research aimed to investigate the antibacterial PEO-NaAlg nanofiber fabrication. The fiber fabrication was examined under various viscosities of electrospinning solution. The electrospun nanofiber fabrication focuses on blending polyethylene oxide (PEO) with a molecular weight of 200-300 kDa, mixed with sodium alginate (NaAlg) of three different viscosities: 150 cP, 300 cP, and 730 cP to study how the viscosity of the solution affects the morphology of electrospun nanofibers. The PEO-NaAlg electrospun nanofiber was enhanced for water insolubility by crosslinking with calcium chloride (CaCl₂). The additional antibacterial property of the nanofiber by loading an antibacterial agent potentially against the growth of bacteria, was investigated. Antibacterial drug, ciprofloxacin at varying amounts of 0.05%w/v, 0.20%w/v, and up to 0.25%w/v was loaded to PEO-NaAlg solution and conducted electrospinning. The effectiveness of the antibacterial electrospun nanofiber was evaluated by testing its ability to inhibit the growth of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The inhibition area before and after crosslinking was observed. The results showed that the acquired nanofibber formation required 7%w/v of 200 kDa to 300 kDa of PEO, and blending 1%w/v NaAlg of 150 cP can certainly retain fiber morphology after crosslinking. Moreover, nanofibers loaded with ciprofloxacin effectively inhibit the growth of E. coli.
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Comparative study of vacuum arc-remelting and spark plasma sintering processes on microstructure and corrosion behavior of Cp-Ti for biomedical implant applications
(2025-11-01)
Kunbuala, Neeraphat
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Srirussamee, Kasama
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Phamornnak, Chinnawich
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Tunthawiroon, Phacharaphon
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Hankoy, Montree
Titanium (Ti) and its alloys are widely used for biomedical applications due to their excellent mechanical properties and biocompatibility. However, the selection of an appropriate manufacturing process is critical to ensuring the optimal performance of Ti-based implants. This study investigates the effects of two fabrication methods –vacuum arc remelting (VAR) and spark plasma sintering (SPS) – on the microstructure and corrosion behavior of commercially pure titanium (Cp-Ti). VAR-Ti ingots were fabricated using arc-melting with multiple remelting cycles, whereas SPS-Ti specimens were sintered from Ti powders under pressure and pulsed current in a high-vacuum environment. Both specimens were subsequently heat-treated at 800 °C and furnace cooled. Microstructural characterization revealed coarser grains and porosity in VAR-Ti, while SPS-Ti showed refined, uniform α-phase structures. Electrochemical tests, including OCP, polarization, EIS, and ICP-MS, indicated slightly enhanced corrosion resistance in SPS-Ti, attributed to its defect-free microstructure. XPS analysis confirmed TiO<inf>2</inf> surface formation on both samples. Additionally, both materials exhibited high ductility and excellent biocompatibility, with cell viability exceeding ISO 10993-5 thresholds. These findings highlight the advantage of SPS in producing defect-minimized Cp-Ti with improved corrosion behavior for biomedical applications.
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Phase-Pure Hydroxyapatite/β-Tricalcium Phosphate Scaffolds from Ultra-Pure Precursors: Composition Governs Porosity, Strength, and SBF Kinetics
(2025-11-01)
Monviset, Panuwat
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Srirussamee, Kasama
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Khantachawana, Anak
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Naruphontjirakul, Parichart
Biphasic calcium phosphate (BCP)scaffolds comprising hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP) were produced from ultra-pure precursors and processed under an α-TCP–avoiding schedule (1100 °C, 2 h). Quantitative X-ray diffraction (Rietveld/Profex) detected no α-TCP above the ~1 wt% limit of detection and quantified post-sintering phase fractions (wt% HA/β-TCP): 99.26/0.74, 68.51/31.49, and 27.57/72.43. Across compositions, SEM/ImageJ yielded similar mean macropore sizes (≈71–80 µm), while open porosity increased with the HA fraction (27.5 ± 1.8%, 39.1 ± 2.0%, 57.1 ± 2.4%). Compressive strength decreased accordingly (1.07 ± 0.25, 0.24 ± 0.01, 0.05 ± 0.02 MPa), consistent with non-load-bearing use. In ISO-compliant simulated body fluid (28 d), medium pH remained stable (7.33–7.43); mass loss and early Ca<sup>2+</sup> depletion increased with β-TCP content, consistent with more extensive surface apatite formation in β-TCP-rich scaffolds. Collectively, these data are consistent with a composition-dependent sequence—β-TCP content → densification/porosity → strength → degradation/apatite kinetics—within the tested conditions and inform parameter-based tuning of BCP scaffolds for non-load-bearing indications (e.g., alveolar ridge preservation, craniofacial void filling).
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Co-stimulation with piezoelectric PVDF films and low intensity pulsed ultrasound enhances osteogenic differentiation
(2025-08-01)
Tandon, Biranche
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Aguilar Cosme, Jose R.
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Xue, Ruikang
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Srirussamee, Kasama
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Aguilar-Tadeo, Julio
Bone tissue engineering has emerged as a promising approach to address the challenges of bone fracture repair and regeneration. The application of external stimuli (mechanical and electrical) can drive specific cellular responses and osteogenic differentiation, leading to the development of more effective treatments. Piezoelectric materials modulate cellular proliferation and osteogenic differentiation under both static (without mechanical stimulation) and dynamic (with mechanical stimulation) conditions, activating distinct gene expression pathways. In this work, we investigate the combinatorial effect of poly (vinylidene fluoride) (PVDF) poled and non-poled films, and low-intensity pulsed ultrasound (LIPUS) on early-stage osteogenic differentiation of mouse pre-osteoblasts. Static culture with PVDF poled films enhanced Runx2 and Col1α1 expression without impacting alkaline phosphatase (ALP) activity. Inhibition of ERK phosphorylation using U0126 in PVDF poled films resulted in a ~ 6–8-fold increase in ALP activity, suggesting the involvement of an alternative pathway in osteogenic differentiation. Dynamic culture with LIPUS generated an electric potential of approximately 500 mV across PVDF films and an electrical field of 0–10 mV mm<sup>−1</sup>. Co-stimulation led to a ~3-fold increase of ALP activity on stimulated PVDF compared to unstimulated films. This study underscores the potential of piezoelectric materials as non-invasive electrical stimulators to enhance the efficacy of ultrasound-based therapies for bone fracture repair.
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Assessment of the utility of chitosan nanoparticles and microfibers in drug delivery applications of sulfamethoxazole and ciprofloxacin
(2025-05-07)
Soontorntepwarakul, Nussara
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Boonyarattanakalin, Kanokthip
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Fukasem, Poowadon
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Somkhuan, Sitthinan
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Srirussamee, Kasama
The objective of this research was to explore the suitability of chitosan (CS) in the form of nanoparticles (NP) and microfibres (MF) for oral delivery applications related to low solubility antibiotic drugs sulfamethoxazole and ciprofloxacin. The ionic gelation method in conjunction with freeze-drying was used to produce crosslinked chitosan material. The dynamic light scattering (DLS) technique was used to characterize the particle size and polydispersity index (PDI). Surface morphology was analyzed using scanning electron microscopy (SEM). The antibiotic drugs ciprofloxacin (CPF) and sulfamethoxazole (SMO) were loaded onto the chitosan nanoparticle and microfibre materials. The degree of loading and the release kinetics were investigated using high-performance liquid chromatography (HPLC) and a UV-visible spectrophotometer, respectively. CS itself has mucoadhesive properties and combined with the more rapid release of drug compared to the pure API, or traditional tablet formulations, CS nanoparticles and microfibres have the potential to improve the delivery properties of CPF and also SMO to a lesser extent. This difference can be rationalized on account of their differing physicochemical properties.
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Effects of Surface Finishing Techniques on Properties of NiTi Coil Spring Actuators
(2025-01-01)
Premwattananarakul, Natakorn
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Srirussamee, Kasama
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Tunthawiroon, Phacharaphon
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Kumnorkaew, Theerawat
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Phukaoluan, Aphinan
This research aims to investigate the effects of surface finishing techniques on phase transformation, topography, and recovery force of NiTi coil springs designed for actuator applications. The NiTi wire, with a diameter of 1 mm, was fabricated into a helical spring with an index of 9 and 20 active coils. The spring was subsequently annealed at 550 °C for 30 min and then quenched in water. The surface finishing techniques applied to the NiTi springs included chemical etching, mechanical polishing, and sand blasting. It was observed that mechanical polishing had a strong impact on topography than both chemical etching and sand blasting. After mechanical polishing, the topography of NiTi coil springs slightly changed compared to the annealed spring. The examined surface was smooth and glistening, with a surface roughness R<inf>a</inf> of 0.175 ± 0.006 µm, nearly identical to that of the annealed spring R<inf>a</inf> of 0.116 ± 0.021 µm. Chemical etching produced a surface oxide, yet the surface became rough due to an uncontrollable chemical reaction, i.e., the R<inf>a</inf> value obtained from chemical etched surface (1.177 ± 0.156 µm) was higher than that of the mechanically polished spring. Meanwhile, sand blasting provided a blue-shaded surface corresponding to an excessive R<inf>a</inf> of 1.952 ± 0.204 µm. The DSC results revealed two peaks of R-phase and martensite transformation in the cooling curve, with only austenite transformation appearing on the heating curve. According to the DSC curve, all surface finishing techniques can reduce the latent heat and affect the associated phase transformations. Consequently, the recovery force of the spring was increased by 2–5 times the initial length. The maximum stiffness (k) of 0.129 N/mm and recovery force for the surface-finished springs were provided by mechanical polishing, while the minimum values of 0.104 N/mm were yielded by sand blasting. All experimental findings offer a framework for the development of actuator springs enhanced through each surface finishing technique.
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Influence of the Oxide Film on the Performance and Corrosion Resistance of TiNiCu Shape Memory Alloys as the Heat Engine Actuator
(2024-10-01)
Phukaoluan, Aphinan
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Srirussamee, Kasama
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Khantachawana, Anak
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Chuchonak, Monthon
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Tunthawiroon, Phacharaphon
Shape memory alloys (SMAs) are utilized as an actuator for the heat engine to harvest energy from low-temperature geothermal sources, such as hot springs, which convert thermal energy into mechanical work. However, the alloy processing and engine design still require optimization to improve performance and durability. To discuss their potential as heat engine actuator, this study investigated the influence of oxide films on the TiNiCu SMAs in terms of surface and structural properties, recovery forces, and corrosion resistance. The results show that the surfaces of the etched samples were relatively coarser than those unetched with lower oxygen content. With the presence of oxide film, the Austenite Finish Temperature (Af) temperature of the unetched SMAs was lower with R-phase transformation. Also, it provided higher recovery force at above Af temperature (as high as 8.3 N at 70-mm displacement). Furthermore, the corrosion resistance of the unetched SMAs was higher than the etched samples, as analyzed by open-circuit potential and linear polarization in natural spring water at 70°C. These findings imply that the presence of oxide film could be beneficial for the SMAs when used as an actuator for heat engines, although it may require further study to investigate its impact on the fatigue behavior of the alloys.
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Assessment of the Utility of Chitosan in Drug Delivery of Sulfamethoxazole
(2024-01-01)
Soontorntepwarakul, Nussara
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Boonyarattanakalin, Kanokthip
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Srirussamee, Kasama
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Paul Gleeson, M.
The objective of this research was to develop chitosan (CS) nanoparticles (NP) and microfibres (MF) for oral delivery applications related to low solubility drugs. The ionic gelation method in conjunction with freeze-drying was used to produce crosslinked chitosan material. Dynamic light scattering (DLS) was used to characterize particle size and polydispersity index (PDI). Surface morphology was analyzed using scanning electron microscopy (SEM). The antibiotic drug sulfamethoxazole (SMO) was loaded onto the chitosan nano/micro material. The degree of loading, loading efficiency and the release kinetics were investigated using high-performance liquid chromatography (HPLC) and UV-visible spectrophotometry, respectively. We found that CS nanoparticles have the potential to improve the delivery properties of SMO due to their more rapid release compared to microfibres or traditional tablet formulations.
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Microstructure and mechanical properties of Ti-Zr alloys fabricated by two-step spark plasma sintering from TiH2 and ZrH2 powders
(2023-01-01)
Banjongaxsorn, Kunpot
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Khantachawana, Anak
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Watanabe, Chihiro
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Srirussamee, Kasama
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Kondoh, Katsuyoshi
Ti is well-known for its high strength-to-weight ratio and biocompatibility. It can be alloyed with Zr to improve mechanical properties. Currently, Ti-Zr alloys can be fabricated by powder metallurgy using Ti and Zr powders, although high oxidation reactivity and cost could still be an issue. In this study, premixed TiH<inf>2</inf> and ZrH<inf>2</inf> powders were used to prepare Ti-Zr binary alloys with different Zr contents of 0–30 mass% ZrH<inf>2</inf> via dehydrogenation and sintering by spark plasma sintering (SPS) process. α-Ti and δ-TiH<inf>2</inf> phases coexisted in the sintered Ti-Zr alloys, and a characteristic lamellar microstructure was formed. The tensile strength of the Ti-Zr alloys increased with increasing Zr content due to the solid solution effect, grain refinement and the appearance of δ-TiH<inf>2</inf> phases, although the elongation was reduced. This study shows that the fabricated Ti-Zr alloys possess controllable mechanical properties, which can be beneficial for biomedical and other engineering applications.
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Characterization of Fluoride-added Hydroxyapatite Derived from Eggshells for Dental Application
(2023-01-01)
Uthayaphamornwat, Vilasinee
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Khantachawana, Anak
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Kitiwan, Mettaya
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Srirussamee, Kasama
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Tunthawiroon, Phacharaphon
Hydroxyapatite (HA) is one of the potential biomaterials used for treating dental defects. It can be incorporated with fluoride to enhance its anti-caries properties, though other properties could be dependent on processing technique. Hence, this study aims to characterize the influence of sintering on the properties of fluoride-added HA derived from eggshells. FTIR and XRD techniques are used to characterize the chemical and crystal structures of the samples, whilst dissolution test is carried out to characterize material degradation in the acidic environment. The results show that sintering increased the crystallinity in both HA and fluoride-add HA (F-HA) samples, which corresponds with the enhanced stability during the dissolution test. Moreover, it is also found that the addition of fluoride could further stabilize the material structure, though the impurities found in all the samples still need to be minimized. These findings suggest that sintering and fluoride addition could potentially enhance anti-caries properties of eggshell-derived HA, which could be beneficial for dental application in future subject to further process optimization and analysis.

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