## 1 Introduction  
The development of functional polymeric materials has gained significant attention due to their potential applications in biomedical, food packaging, and environmental fields [1, 2, 3]. Among these materials, natural biopolymers such as starch have emerged as sustainable alternatives to synthetic polymers, owing to their biodegradability, biocompatibility, and widespread availability [4, 5]. However, the inherent limitations of starch-based films, such as poor mechanical strength and thermal instability, have prompted the design of blended polymeric matrices [6, 7]. Recent advancements in intelligent packaging have explored the development of pH-sensitive films utilizing blends of different biodegradable polymers. [PERSON] et al. (2024) investigated the incorporation of anthocyanins from purple potato into chitosan/polyvinyl alcohol/nano-ZnO matrices [8]. The resulting films exhibited enhanced pH responsiveness and antibacterial properties, further broadening the scope of potato-based pH-sensitivefilms in intelligent packaging solutions [8]. Further research by [PERSON] et al. (2023) focused on enhancing the stability and functionality of such films [9]. They incorporated anthocyanins, extracted from purple sweet potato, into a composite film matrix, resulting in improved pH sensitivity and mechanical properties. The optimized film demonstrated reliable performance in monitoring pork freshness and preserving cherry quality [9]. One promising strategy to enhance the limited functional properties involves the incorporation of bioactive agents, particularly natural anthocyanins, and silver nanoparticles (AgNPs). [PERSON] et al. (2017) developed a colorimetric pH indicator film composed of agar, potato starch, and anthocyanin extracts from purple sweet potato (_Ipomoae batatas_) [10]. The film exhibited distinct color changes across a pH range of 2.0 to 10.0, transitioning from red in acidic conditions to green in alkaline environments. This property enabled the film to function effectively as a meat spoilage sensor, indicating freshness through visible color shifts [10]. Silver nanoparticles are well known for their broad-spectrum antimicrobial activity, high surface area, and tunable physicochemical properties [11]. Silver nanoparticles (AgNPs) have emerged as versatile additives in polymer matrices, not only due to their well-documented antimicrobial activity, but also for their capacity to modify and enhance the optical properties of polymers. This enhancement is primarily attributed to localized surface plasmon resonance (LSPR), which imparts unique optical behaviors, such as dichroism and environmental sensitivity, to AgNPs [12]. Green synthesis of AgNPs using plant-based extracts rich in phenolic compounds offers an eco-friendly approach that avoids the use of toxic reducing agents and harsh reaction conditions [13]. In this context, anthocyanin-rich extracts from pigmented native potatoes (_Solanum tuberosum_) serve not only as natural reducing and stabilizing agents during nanoparticle synthesis but also confer antioxidant properties that may enhance the functional performance of the resulting materials [13; 14]. A recent study investigated the incorporation of polymorphic AgNPs into a polyvinyl alcohol (PVA) matrix. The results demonstrated that the nanoparticles retained their dichroic properties upon embedding in the polymer. Furthermore, the morphology of the AgNPs directly influenced the color of the final material: triangular nanoparticles produced a blue hue, spherical particles resulted in yellow, and irregular shapes generated reddish tones [12]. These stable optical characteristics open up new opportunities in optical filters, decorative coatings, and smart materials. Accordingly, AgNPs have also been successfully incorporated into polymer-based systems for contaminant detection [15]. [PERSON] et al. (2022) reported a starch-stabilized AgNPs colorimetric sensor for selective Hg\({}^{2+}\) detection.