he development of a highly selective and sensitive Ba 2+ sensor is crucial because of its industrial, environmental, and biological relevance. This study introduces a novel coated wire barium‑selective electrode incorporating DNA as an ecofriendly natural ionophore in a plastic membrane, utilizing dioctyl phthalate as a plasticizer. The use of DNA as an ionophore provides enhanced selectivity and sensitivity, showcasing a slope of 33.15 mV/decade across a broad concentration range (1 × 10⁻ 5 to 1 × 10⁻ 2 M). The sensor exhibited a rapid response time of 9 s, a wide pH toler‑ ance (2.6–6.9), and good selectivity for Ba 2+ over other cations. Characterization of the membrane using FT‑IR, SEM, and EDX confrmed its structural and morphological features. Practical applicability was demonstrated by detecting Ba 2+ in spiked samples (milk, juice, tap water and urine) with recovery rates of 96.07–98.9%. This DNA‑based approach ofers a promising advancement in ion‑selective electrode technology, with signifcant implications for real‑world Ba 2+ detection.