Atık Toner Tozu Kullanılarak Basit ve Çevre Dostu Bir Yöntemle Grafen Kuantum Noktaların Sentezi, Karakterizasyonu ve Antioksidan Potansiyelinin Belirlenmesi

Abstract

Karbon bazlı kuantum noktaları, yüksek suda çözünürlük, biyouyumluluk ve düşük sitotoksisite gibi olağanüstü fizikokimyasal özellikleri nedeniyle büyük ilgi görmüştür. Ancak geleneksel sentez yolları genellikle pahalı karbon öncülleri, zorlu reaksiyon koşulları içerir ve tehlikeli kimyasallar kullanır. Bu çalışmada, elektronik atıkların önemli bir bileşeni olan atık toner tozu, GQD'lerin sentezi için sürdürülebilir bir karbon kaynağı olarak kullanılmıştır. Atık toner tozu, 200 °C'de hidrotermal koşullar altında etanol ve hidrojen peroksit ile muamele edilmiş ve π–π* ve n–π* geçişlerine karşılık gelen 240 ve 280 nm'de karakteristik emilim tepe noktalarına sahip GQD'ler elde edilmiştir. Atık toner tozunun ve GQD'lerin XRD deseni, atık toner tozunun kristal yapısının dönüşümünü göstermektedir. Sentezlenen GQD'lerin antioksidan potansiyeli DPPH, süperoksit, nitrik oksit temizleme ve indirgeyici güç analizleriyle değerlendirilmiştir. GQD'ler, 500 µg/mL'de %61,36 DPPH inhibisyonu, %70,58 süperoksit radikali ve %41,16 nitrik oksit ile kayda değer serbest radikal temizleme aktivitesi sergilemiştir. Bu çalışma kapsamında elde edilen sonuçlar atık toner tozunun hem çevresel hem de biyomedikal faydalar sunan önemli antioksidan aktiviteye sahip yüksek değerli nanomalzemelere geri dönüştürülmesinin uygulanabilirliğini vurgulamaktadır.

Keywords

• Elektronik atıklar
• Toner tozu
• Ekonomik sentez
• Grafen kuantum noktalar
• Antioksidan

Ethical Statement

Bu araştırmada insan katılımcılar veya hayvanlar yer almadığından etik onay gerekmemektedir. Yazar, ilgili tüm etik kurallara uyulduğunu teyit etmektedir.

Synthesis of Graphene Quantum Dots using Waste Toner Powder in a Simple and Environmentally Friendly Approach, Characterization and Determination of their Antioxidant Potential

Abstract

Carbon based quantum dots (GQDs) have attracted considerable attention due to their exceptional physicochemical properties such as high water solubility, biocompatibility and low cytotoxicity. However conventional synthesis routes often involve expensive carbon precursors, harsh reaction condition and use hazardous chemicals. In this study waste toner powder a major component of electronic waste was utilized as a sustainable carbon source for the synthesis of GQDs. Waste toner powder was treated with ethanol and hydrogen peroxide under hydrothermal conditions at 200 °C, yielding GQDs with characteristic absorption peaks at 240 and 280 nm corresponding to π–π* and n–π* transitions. The XRD pattern of waste toner powder and GQDs indicate transformation of crystal structure waste toner powder. The antioxidant potential of the synthesized GQDs was evaluated through DPPH, superoxide, nitric oxide scavenging and reducing power assays. GQDs exhibited notable free radical scavenging activity with 61.36% DPPH inhibition, 70.58% superoxide radical scavenging and 41.16% nitric oxide scavenging at 500 µg/mL. The antioxidant capacity was further supported by reducing power activity demonstrating their ability to donate electrons and neutralize reactive species. These findings highlight the feasibility of recycling waste toner powder into high value nanomaterials with significant antioxidant activity offering both environmental and biomedical benefits.

Keywords

• Electronic waste
• Toner powder
• Economic synthesis
• Graphene quantum dot
• Antioxidant

Ethical Statement

This research did not involve human participants or animals, and thus did not require ethical approval. The author confirm that all relevant ethical guidelines were followed.

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