Self-cleaning menstrual cups with plant-based biodegradable superabsorbent fibrous tablets for hygienic and sustainable Period Care 

Menstrual cups are reusable, low-waste alternatives to pads and tampons, but adoption is limited by hygiene concerns related to blood residue and bacterial biofouling, as well as the risk of spillage during removal. To address these challenges, we developed an integrated “self-cleaning” menstrual cup system combining a silicone oil-infused cup surface with a biodegradable, plant-based superabsorbent fibrous tablet.

Commercial silicone cups were treated with silicone oil to create a liquid-infused, low-adhesion surface. Oil infusion reduced bacterial biomass adhesion across cup types, with the best-performing cup showing approximately a three-fold reduction in Escherichia coli biomass compared with untreated silicone. Thrombin generation parameters remained statistically unchanged, indicating that the modification did not increase thrombogenicity. Clotting time on the optimized cup increased from 699 to 949 s after infusion, supporting reduced clot adhesion and improved self-cleaning behavior.

To minimize spillage, calcium-crosslinked alginate fibers were fabricated by wet spinning and air drying. After optimization of alginate and CaCl₂ concentrations, the selected formulation absorbed 8 mL g⁻¹ of water and up to 15 mL g⁻¹ of whole human blood. The fibers were compressed and die-cut into cup-compatible tablets capable of retaining blood volumes comparable to cup capacity, enabling cleaner emptying.

The fibers neither promoted nor inhibited E. coli or Staphylococcus aureus growth and completely degraded within 4 days in PBS. Overall, this system combines anti-biofouling surfaces with biodegradable absorbent tablets to improve menstrual cup hygiene, usability, and sustainability.