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Ultrasound-assisted green extraction of shrimp-waste chitosan for bioactive aerogel scaffolds
Soni Thakur, Amal M. Sindi, Rahul Dev Bairwan, Rasha A. Mahmoud, Eman Alfayez, Nurul Fazita Mohammad Rawi, Kanchan Jha, H.P.S. Abdul Khalil
Vol. 20., No.2., Pages 197-214, 2026
DOI: 10.3144/expresspolymlett.2026.16
Corresponding author: H.P.S. Abdul Khalil

GRAPHICAL ABSTRACT

ABSTRACT

This research presents an eco-friendly approach for extracting chitosan from shrimp shell waste through ultrasound-assisted extraction (UAE) to prepare biocompatible aerogel scaffolds for biomedical applications. The study investigates the influence of various ultrasonic treatment times (10, 20, 30, 40 min) on the yield and structural and physicochemical properties of the extracted chitosan via characterization using Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). Among the tested conditions, the 30 min UAE-treated chitosan aerogels showed optimal porosity and structural integrity. Biocompatibility of the aerogels was evaluated, and the results confirmed their non-cytotoxic nature. The bioactivity of the chitosan aerogels was evaluated in terms of their in vitro wound closure ability and antibacterial properties. The aerogels demonstrated a wound closure rate of around 51% after 72 h, significantly higher than the untreated control (37%). In addition, they exhibited clear antibacterial activity against Escherichia coli and Staphylococcus aureus. This sustainable extraction and fabrication method not only adds value to marine waste but also produces functional biomaterials with potential applications in wound healing, tissue engineering, and regenerative medicine, supporting global efforts toward sustainability and circular bioeconomy.


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Published by:

Budapest University of Technology and Economics,
Faculty of Mechanical Engineering, Department of Polymer Engineering