Enzymatic Oligomerization of Ampyrone- and Phenylhydrazine-Based Monomers: Structural, Thermal, and Antioxidant Functional Analysis

Abstract

In this study, 2,4-dihydroxybenzaldehyde was subjected to separate condensation reactions with phenylhydrazine and ampyrone (4‑amino antipyrine), yielding a hydrazine‑based monomer (M‑PHy) and an azomethine monomer (M‑Amp), respectively. Both monomers were subsequently polymerized via horseradish peroxidase/hydrogen peroxide (HRP/H₂O₂)–mediated enzymatic oxidative oligomerization, affording two novel oligomeric products, O‑PHy and O‑Amy. The chemical structures of all synthesized compounds were confirmed by FT‑IR, UV‑Vis, and ¹H NMR spectroscopic analyses. Molecular weight distributions of the oligomers were determined using gel permeation chromatography (GPC). Thermal properties were evaluated by thermogravimetric analysis (TGA), revealing initial decomposition temperatures of 178 °C for O‑PHy and 192 °C for O‑Amy, with residual masses of 16.5% and 15.6% at 1000 °C, respectively. Surface morphologies of the oligomers were examined by scanning electron microscopy (SEM), demonstrating distinct microstructural features associated with their molecular architectures. These findings highlight the successful synthesis, structural verification, and physicochemical characterization of two new enzymatically derived oligomers.

Keywords

• HRP/H2O2
• enzymatic reaction
• oligomerization
• hydrazine
• ampyrone
• macromolecules.

Supporting Institution

This study was carried out at Istanbul Health and Technology University.

Ethical Statement

This study adheres to scientific research and publication ethics. The study does not involve any human or animal experiments, surveys, interviews, clinical procedures, or processes involving personal data that would require ethical committee approval. All experimental work was conducted in a laboratory setting focusing on chemical synthesis and characterization. There are no conflicts of interest in this study, and all authors have made significant contributions and approved the final version of the article.

Thanks

This study was made possible thanks to the laboratory infrastructure, research facilities, and academic support provided by Istanbul University of Health and Technology. I would like to express my sincere gratitude to Istanbul University of Health and Technology for their contributions, guidance, and the scientific environment they provided throughout the research process.

Ampiyon ve Fenilhidrazin Tabanlı Monomerlerin Enzimatik Oligomerizasyonu: Yapısal, Termal ve Antioksidan Fonksiyonel Analizi

Abstract

Bu çalışmada, 2,4-dihidroksibenzaldehit, fenilhidrazin ve ampiron (4‑amino antipirin) ile ayrı ayrı kondenzasyon reaksiyonlarına tabi tutularak sırasıyla hidrazin‑türevli bir monomer (M‑PHy) ve bir azometin monomeri (M‑Amp) elde edilmiştir. Her iki monomer daha sonra yaban turpu peroksidazı/hidrojen peroksit (HRP/H₂O₂) aracılı enzimatik oksidatif oligomerizasyon ile polimerleştirilmiş ve iki yeni oligomerik ürün, O‑PHy ve O‑Amy, sentezlenmiştir. Tüm sentezlenen bileşiklerin kimyasal yapıları FT‑IR, UV‑Vis ve ¹H NMR spektroskopik analizleri ile doğrulanmıştır. Oligomerlerin moleküler ağırlık dağılımları jel geçirgenlik kromatografisi (GPC) kullanılarak belirlenmiştir. Termal özellikler termogravimetrik analiz (TGA) ile değerlendirilmiş; O‑PHy için 178 °C ve O‑Amy için 192 °C başlangıç bozunma sıcaklıkları ile sırasıyla 1000 °C’de %16,5 ve %15,6 artık kütle değerleri elde edilmiştir. Oligomerlerin yüzey morfolojileri taramalı elektron mikroskobu (SEM) ile incelenmiş ve moleküler yapılarıyla ilişkili belirgin mikro yapısal özellikler gözlemlenmiştir. Bu bulgular, iki yeni enzimatik olarak türetilmiş oligomerin başarılı sentezini, yapısal doğrulamasını ve fizikokimyasal karakterizasyonunu ortaya koymaktadır.

Keywords

• HRP/H₂O₂
• enzimatik reaksiyon
• oligomerizasyon
• hidrazin
• ampiron
• makromoleküller

Supporting Institution

Çalışma İstanbul Sağlık ve Teknoloji Üniversitesi' nde gerçekleştirilmiştir.

Ethical Statement

Bu çalışmada bilimsel araştırma ve yayın etiğine uyulmuştur. Çalışmada herhangi bir etik kurul izni gerektiren insan veya hayvan deneyi, anket, mülakat, klinik uygulama ya da kişisel veri içeren bir süreç bulunmamaktadır. Tüm deneysel çalışmalar laboratuvar ortamında kimyasal sentez ve karakterizasyon üzerine gerçekleştirilmiştir. Çalışmada çıkar çatışması bulunmamaktadır ve tüm yazarlar çalışmaya anlamlı katkı sağlamış olup makalenin son halini onaylamıştır.

Thanks

Bu çalışma, İstanbul Sağlık ve Teknoloji Üniversitesi’nin sağladığı laboratuvar altyapısı, araştırma olanakları ve akademik destek sayesinde gerçekleştirilmiştir. Araştırma sürecindeki katkıları, yönlendirmeleri ve sağladıkları bilimsel ortam için İstanbul Sağlık ve Teknoloji Üniversitesi’ne içtenlikle teşekkür ederim.

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