Biodegradable, water-resistant, smart cellulose-based drinking straws from agricultural biomass with detection of adulterants in beverages

Abstract

Drinking straws due to their non-degradability, large consumption, and poor recyclability, pose a great risk to the environment and human health. Leaf stalk from papaya biomass was modified strategically via delignification and silanization for fabricating drinking straws. The straws show high water resistance (∼8 h), mechanical strength (50.1 MPa tensile strength, 6.7 MPa flexural strength, and 26.7 MPa compressive strength), hydrophobicity (contact angle ∼90.2°), solvothermal stability (0–80 °C), migration within standard limits (<60 mg/kg), low swelling (∼3.83 times) and anti-fizzing. The papaya straws post-functionalization were biodegradable (∼28 days) with lower ecological impacts. The smart straws show color change with pH variation (3−11), making them suitable for detecting spoilage and urea adulteration (1 mg/ml) in beverages and milk samples, respectively. The straws showed higher performance than paper straws with low water resistance (∼30 mins), mechanical strength (∼14 MPa), fizzing, and plastic straws with low strength (∼22 MPa) and non-biodegradability. The study provides a facile, scalable, environment-friendly, strategy for preparing high-performance straws from renewable biomass with improved properties and the ability to detect spoilage in fruit juices and milk beverages. © 2025