Suranaree Journal of Science and Technology

COMPARATIVE STUDY OF ANTIOXIDANT, ANTI-INFLAMMATORY, AND ANTIMICROBIAL ACTIVITIES OF LAC DYE AND D&C RED No. 27

Worrakanya Narakornwit — 2025-07-04

Lac dye and D&C red No. 27, natural and synthetic dye, are commonly used in pharmaceuticals and cosmetics. Their antioxidant, anti-inflammatory, and antimicrobial activities were investigated using the DPPH, the thermal inhibition of egg albumin protein denaturation and the agar diffusion methods, respectively. Lac dye demonstrated stronger antioxidant activity than ascorbic acid (the positive control) and D&C red No. 27, with EC₅₀ values of 2.03±0.08, 8.28±0.02, and 397.87±1.16 µg/ml, respectively. D&C red No. 27 exhibited anti-inflammatory activity (EC₅₀ value 114.61±8.46 µg/ml) higher than diclofenac sodium (EC₅₀ 754.11±1.42 µg/ml), whereas lac dye induced inflammation with an IC₅₀ value of 136.40±2.31 µg/ml. At a concentration of 0.25% w/v, lac dye effectively inhibited the growth of Staphylococcus aureus, Escherichia coli, and Porphyromonas gingivalis, producing clear inhibition zones of 17.7±0.6, 18.3±0.6, and 24.3±0.6 mm, respectively. However, lac dye displayed antifungal activity against Candida albicans and Candida tropicalis compared to the solvent (PEG 400) at a concentration of 2% w/v. D&C red No. 27 inhibited against S. aureus, E. coli, and P. gingivalis, with clear zones of 15.3 ± 0.6, 15.3 ± 0.6, and 22.3 ± 0.6 mm, respectively, at a concentration of 0.25%. Notably, D&C red No. 27 demonstrated strong antimicrobial activity against Propionibacterium acnes, with an inhibition zone of 41.0±1.0 mm, which surpassed the 24.0±1.7 mm zone produced by lac dye at the same concentration of 0.25% w/v. However, D&C red No. 27 exhibited only a limited ability to inhibit both types of fungi. These findings suggest that both dyes may offer valuable benefits for the development of future formulation.

PHYSICAL PROPERTIES AND BIOACTIVITIES OF CURCUMIN-LOADED IN-SITU IMPLANT

Napaphol Puyathorn — 2025-07-04

Curcumin, the important active component in turmeric extracts, has gained significant attention demonstrating notable effectiveness across a wide range of human pathological conditions. This study explores the development and characterization of borneol and ibuprofen-based in situ implant (ISI) systems loaded with curcumin, designed for advanced therapeutic applications. Curcumin ISI solution enabled self-transformation into matrix at 40% w/w concentration. Ibuprofen and borneol enhanced curcumin transformation at lower concentration. These ISI systems exhibited low viscosity and swift transformation aiding for their administration by injection. Macroscopic and cross-sectional imaging provided insights into their phase inversion process. Curcumin-loaded borneol-based ISI demonstrated high antioxidant activity. Both curcumin-loaded borneol-based and ibuprofen-based ISIs showed efficient antimicrobial activities against related periodontitis pathogens. These findings underscore the potential of curcumin-loaded borneol and ibuprofen-based ISI systems as promising candidates for localized drug delivery, particularly in treating periodontitis.

PRELIMINARY STUDY ON ADAPTIVE KNOT STRATEGIES IN CUBIC B-SPLINES FOR EFFICIENT DIFFERENTIAL EQUATION SOLVING

Wisut Kitchainukoon — 2025-07-01

This preliminary study explores a modest approach that combines cubic B-splines with an adaptive knot refinement algorithm for solving differential equations. The method adjusts knot placement dynamically based on local error estimates, aiming to improve solution accuracy without manual intervention. While the enhancements in accuracy may be limited, particularly in areas with rapid solution changes, the approach provides a foundational framework for further research. Although the improvement in accuracy may seem modest, it lays a solid foundation for further refinement and development, paving the way for even greater advancements in computational precision and efficiency.

PULSED Nd:YAG LASER-SYNTHESIZED SILVER NANOPARTICLES WITH HIGH SENSITIVITY FOR GLUCOSE DETECTION

Nurul Hidayat — 2025-06-23

Diabetes Mellitus (DM) affects not only adults but also children, leading to an urgent need for the development of a reliable glucose sensors. This study introduces a simple method to develop a Localized Surface Plasmon Resonance (LSPR)-based glucose sensor utilizing silver nanoparticles (AgNPs). AgNPs were synthesized using pulsed Nd:YAG laser ablation in liquid at different laser-pulse diameters ranging from 1 mm to 5 mm. The wavelength, energy, and frequency of the Nd:YAG laser were fixed at 1064 nm, 200 mJ, and 4 Hz, respectively. The morphology of AgNPs was observed to be spherical, with an average diameter of 42.5 nm. Analysis of the UV-Vis results showed that the interaction of AgNPs with glucose at various concentrations (i.e., 0–10%), resulted in changes in the LSPR wavelength. The wavelength shifted to longer values as the glucose concentration increased. The AgNPs’ sensing sensitivity to detect glucose was 0.421 nm/%, with excellent linearity (0.98) and a detection range from 0% to 10%. These findings provide significant contributions to the development of reliable glucose sensors, with important application prospects in the management of diabetes mellitus.

INFLUENCE OF ALKALI-EARTH IONS ON 1.06 µm NEAR INFRARED EMISSION OF ND3+-DOPED LITHIUM ALUMINOPHOSPHATE GLASS FOR LASING APPLICATION

Phalada Thongyoy — 2025-06-13

The influence of the alkali-earth ions (Mg²⁺, Ca²⁺, Sr²⁺) on structural (FTIR) and spectroscopic (optical absorption and near infrared emission) properties of Nd³⁺-doped lithium aluminophosphate glasses were systematically examined and discussed. Under an excitation wavelength of 580 nm, the emission spectra of Nd³⁺-doped glasses showed three prominent peaks at 900, 1058, and 1327 nm, it was related to the ⁴F_3/2 ⁴I_9/2, ⁴I_11/2, and ⁴I_13/2 transitions, respectively. It was found that the peak emission intensity occurs at a wavelength of 1058 nm. The were calculated by applying Judd-Ofelt theory to the absorption and emission measurements, which resulted in the radiative transition probability and stimulated emission cross-section being calculated. As a result, when compared to , , and , have a larger compositional dependency on ionic radius and modifier content. In addition, it was found that the stimulated emission cross-section of , respectively. The luminescence intensity is greatly increased, and the underlying mechanism is clearly seen when cationic replacements of Sr²⁺, Ca²⁺, and Mg²⁺ are carried out. The research proved that spectroscopic properties of trivalent Nd³⁺ depend significantly on the kind of presence of alkali-earth ions in glass host matrices and could be used as a lasing application.