https://www.um.edu.mt/library/oar/handle/123456789/2066 2026-08-05T08:55:56Z 2026-08-05T08:55:56Z Camilleri, Josmar Agius Anastasi, Anthea Briffa, Sophie Marie https://www.um.edu.mt/library/oar/handle/123456789/148408 2026-08-05T08:43:03Z 2025-01-01T00:00:00Z

Title: Detection, quantification, and characterisation of microplastics in Maltese bottled water Authors: Camilleri, Josmar; Agius Anastasi, Anthea; Briffa, Sophie Marie Abstract: Plastics play a pivotal role in various industries owing to their versatility in engineering their physical, mechanical, and chemical properties while exploiting their remarkable durability, light-weight nature, and cost-effectiveness. Yet, their widespread use has led to the pollution of Earth’s water systems. Over time, plastic waste degrades into microplastics, particles smaller than 5 mm. Recent studies have highlighted the growing concerns associated with microplastics, especially in bottled beverages, including bottled water, with associated hazards still in the very early stages of being fully understood. Furthermore, the global understanding of the extent of microplastic contamination in the environment and along the food chain remains limited. This study aimed to detect, quantify, and characterise microplastics in bottled drinking water produced and sold in Malta. Samples from five brands were filtered, stained with Nile red, and quantified using fluorescence microscopy. The average microplastic concentration was found to be 35,877 ± 23,542 particles per litre, with 84% of samples exhibiting contamination, which was noted to be statistically significant. The average particle diameter was measured to be 2.3696 ± 0.0035 µm. Raman spectroscopy was used to chemically characterise 10 larger particles per brand (i.e., 50 samples), identifying the presence of cellulose, polyurethane, polymethyl methacrylate, polyethylene, and smaller quantities of other polymers. Morphological analysis classified 36 of the larger particles as fragments and 14 as fibres. Excluding laboratory-introduced contamination, the primary source of microplastic contamination in the analysed bottled water was traced to the bottle caps. Description: Supplementary material is available within this record.

2025-01-01T00:00:00Z Zhou, Xingxing Xin, Jie Wang, Cheng Qian, Kun Tao, Xuewei Ba, Zhixin Xue, Feng Bai, Jing Mallia, Bertram Dong, Qiangsheng https://www.um.edu.mt/library/oar/handle/123456789/144944 2026-03-16T15:10:05Z 2025-01-01T00:00:00Z

Title: Advances toward self-healing coatings on Mg alloys for active corrosion protection Authors: Zhou, Xingxing; Xin, Jie; Wang, Cheng; Qian, Kun; Tao, Xuewei; Ba, Zhixin; Xue, Feng; Bai, Jing; Mallia, Bertram; Dong, Qiangsheng Abstract: Magnesium (Mg) alloys with high specific strength, light weight, and natural biodegradability are promising candidates for applications in automotive industry and biodegradable medical devices. However, their wide employment is hindered by their rapid corrosion behavior. Protective coatings provide a potential approach to extending the service period, but damage to these coatings often leads to local corrosion and even premature failure. To address this issue, self-healing coatings have been developed for providing long-term and reliable protection, even in the presence of defects. This paper summarizes recent progress in self-healing coatings on Mg alloys, with a focus on their uni- and multistimuli responsive mechanisms. A typical self-healing coating is composed of a physical layer, inhibitors, and inhibitor containers. Herein, the loading and release of inhibitors are crucial for the design of self-healing coatings. On the one hand, inhibitors can be directly doped/filled into the protective layer and released in response to environmental changes and coating degradation. On the other hand, inhibitors may be encapsulated into micro/nano-containers and released upon being triggered by ions, pH, light, heat, potential and moisture. Additionally, this review presents advanced characterization techniques and systematic evaluation methods for assessing self-healing functionality. Ultimately, the emerging challenges and research priorities in the development of self-healing coatings for Mg alloys are comprehensively discussed.

2025-01-01T00:00:00Z Zhou, Siyue Xu, Yidong Lin, Yehao Liu, Junyu Zhang, Min Buhagiar, Joseph A. Chen, Haixia https://www.um.edu.mt/library/oar/handle/123456789/143432 2026-02-04T12:43:28Z 2026-01-01T00:00:00Z

Title: Mulberry leaf-derived bioactive constituents on diabetes : structure, extraction, quality analysis, and hypoglycemic mechanisms Authors: Zhou, Siyue; Xu, Yidong; Lin, Yehao; Liu, Junyu; Zhang, Min; Buhagiar, Joseph A.; Chen, Haixia Abstract: (1) Background: Diabetes mellitus is a chronic metabolic disease with a rising global prevalence. Mulberry leaf (ML), a traditional medicinal and edible plant, possesses notable hypoglycemic effects and has a long history of usage. This review aims to systematically consolidate the research progress on the hypoglycemic constituents derived from ML, including their chemical structure, extraction methods, quality analysis techniques, and hypoglycemic mechanisms. (2) Methods: Adhering to the Preferred Reporting Items for Systematic Reviews (PRISMA 2020) guidelines, a comprehensive literature search was conducted using Web of Science and PubMed databases to find relevant studies published between 2015 and 2025. (3) Results: This review evaluates both conventional and modern techniques such as water extraction, ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), and enzyme-assisted extraction (EAE), highlighting their advantages and limitations when applied on ML. Additionally, this review examines the analytical techniques applied in the quality control of ML and its constituents. This is complemented by a summary of hypoglycemic mechanisms, focusing on the inhibition of oxidative stress, amelioration of insulin resistance, regulation of related enzyme activity, and modulation of gut microbiota. (4) Conclusions: ML demonstrates considerable potential for treating diabetes. However, further studies are needed for new drug discovery based on new ML-derived bioactive constituents, highly efficient extraction methods, quality analysis techniques, and underlying mechanisms.

2026-01-01T00:00:00Z Xin, Jie Li, Qiang Wang, Cheng Chu, Chenglin Xue, Feng Yang, Youwen Giordmaina, Ryan Buhagiar, Joseph P. Dong, Qiangsheng Bai, Jing https://www.um.edu.mt/library/oar/handle/123456789/142086 2025-12-10T12:50:17Z 2025-01-01T00:00:00Z

Title: Pore-size-dependent mechanical properties and biodegradation behavior of biomedical Zn-Li alloy scaffolds Authors: Xin, Jie; Li, Qiang; Wang, Cheng; Chu, Chenglin; Xue, Feng; Yang, Youwen; Giordmaina, Ryan; Buhagiar, Joseph P.; Dong, Qiangsheng; Bai, Jing Abstract: Zn-Li alloys have emerged as promising candidates for bone repair applications due to their excellent mechanical properties and osteogenic potential. In this study, porous Zn-0.7Li scaffolds were fabricated via infiltration casting, with adjustable spherical pore sizes to achieve high porosity and thin-walled structures. Increasing pore size from 550 μm to 950 μm was accompanied by a corresponding elevation in scaffold porosity from 65.6 % to 71.2 % and a concurrent increase in the average wall thickness from 0.21 mm to 0.31 mm. Herein, the compressive yield strength decreased exponentially with rising porosity, while the degradation weight loss rate correlated linearly with specific surface area. The compressive yield strength of Zn-Li scaffolds were enhanced by solid solution strengthening and β-LiZn4 phase on the Zn matrix, superior to Zn-Mg alloy and pure Zn scaffolds at equivalent porosity. Besides, Zn-0.7Li scaffolds showed accelerated degradation due to their larger specific surface area. Based on the evolution of pore structure and mechanical properties during degradation, a mechanical performance decay model was established, which predicted the mechanical half-life of the Zn-0.7Li scaffolds as 61–122 days. This study provides insights into the quantitative relationship between pore structure and physicochemical properties of biodegradable bone repair materials, exploring feasible technical routes for developing high-performance scaffolds.

2025-01-01T00:00:00Z