A floating 3D-printed grid used sunlight to break down an antibiotic

The reusable plastic-and-titanium dioxide grids completely degraded ciprofloxacin in about two hours of natural sunlight.

Editorial illustration — not from the study.

The team made grids from a fluorinated plastic called PVDF-HFP and titanium dioxide using 3D printing and salt leaching. This produced interconnected pores while allowing the grid’s shape and porosity to be controlled, and the finished material remained mechanically stable in water.

In tests, the grids degraded 60% of ciprofloxacin in 540 minutes under UV-A radiation. Under natural sunlight, they completely degraded the antibiotic in about 120 minutes, and their photocatalytic activity remained across multiple reuse cycles.

What the grids did

The floating grids combined PVDF-HFP with titanium dioxide, a material that can use light to drive chemical reactions. They had interconnected pores, strong mechanical stability and could be reused. The grids degraded 60% of ciprofloxacin in 540 minutes under UV-A radiation and completely degraded it in about 120 minutes under natural sunlight. The abstract says they maintained their photocatalytic activity across multiple reuse cycles, but does not give the number of cycles.

Why a floating grid matters

A floating, reusable grid that works under natural sunlight could offer a practical format for treating contaminated water without requiring the photocatalyst to remain as a dispersed powder. 3D printing also allows the grid’s geometry and porosity to be adjusted, which the researchers say could support customisable and deployable water-treatment materials.

Evidence and caveats

The evidence comes from photocatalytic degradation tests of ciprofloxacin using the printed grids under UV-A radiation and natural sunlight. The abstract does not report the test-water composition, antibiotic concentration, sunlight conditions or number of reuse cycles. It also describes potential for broader water remediation, but the reported results concern ciprofloxacin rather than a range of contaminants or confirmed full-scale treatment.

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