Extraction of Keratin from Waste Hair Samples for Biotechnological Applications

Abstract

Research on synthetic tissues and tissue engineering platforms has gained significant attention due to the increasing demand for materials with enhanced stability, biocompatibility, low toxicity, and cost-effectiveness. In this context, biomolecule-based polymers have emerged as promising alternatives for biomedical applications. Keratin, a fibrous protein extracted from human hair, represents an abundant and sustainable biomaterial biomaterial source. Its stability is primarily attributed to its high cysteine content enabling disulfide bond formation along with contributions from other amino acids such as proline. In this study, keratin was isolated from waste human hair using urea-based and sodium sulfide-based extraction methods, and their efficiencies were comparatively evaluated. Using 1.0 g hair samples, the urea-based method yielded 11.8±0.7%, while the sodium sulfide method yielded 13.2±1.0%, with batch-to-batch variation below 8%, indicating good reproducibility. The soluble protein concentrations of purified keratin solutions after dialysis were determined as 189.3±12.0 mg/L for the urea method and 256.5±18.0 mg/L for the sodium sulfide method. Structural and morphological analyses confirmed the proteinaceous nature of keratin. The results indicate that the urea-based method in extraction preserves more native-like and amorphous characteristics, whereas the sodium sulfide method induces stronger sulfur-related modifications and partial structural rearrangement.

Keywords

• Keratin isolation
• waste hair samples
• biotechnological applications.

Biyoteknolojik Uygulamalar için Atık Saç Örneklerinden Keratin Ektraksiyonu

Abstract

Sentetik dokular ve doku mühendisliği platformları üzerine yapılan araştırmalar, yüksek kararlılık, biyouyumluluk, düşük toksisite ve maliyet etkinliği sağlayan materyallere duyulan ihtiyaç nedeniyle önemli ölçüde ilgi görmektedir. Keratin, insan saçından elde edilebilen fibröz bir protein olup kolay bulunabilir ve sürdürülebilir bir biyomateryal kaynağıdır. Stabilitesi, başlıca yüksek sistein içeriğine bağlı olarak disülfid bağlarının oluşumu ile sağlanmakta olup, prolin gibi diğer amino asitlerin de katkısı bulunmaktadır. Bu çalışmada, keratin atık insan saçından üre bazlı ve sodyum sülfid bazlı ekstraksiyon yöntemleri kullanılarak izole edilmiş ve bu yöntemlerin etkinlikleri karşılaştırmalı olarak değerlendirilmiştir. 1.0 g saç örneği kullanılarak, üre bazlı yöntem %11.8±0.7 verim sağlarken, sodyum sülfid yöntemi %13.2±1.0 verim elde edilmiş ve her iki yöntemin %8’in altında değişkenlik gösterdiği belirlenmiştir. Diyaliz sonrası saflaştırılmış keratin çözeltilerinin çözünür protein derişimleri üre yöntemi için 189.3±12.0 mg/L, sodyum sülfid yöntemi için ise 256.5±18.0 mg/L olarak belirlenmiştir. Yapısal ve morfolojik analizler, izole edilen keratinin protein yapısını doğrulamıştır. Sonuçlar, keratin ekstraksiyonunda üre bazlı yöntemin daha doğal ve amorf özellikleri koruduğunu, buna karşılık sodyum sülfid bazlı yöntemin daha güçlü sülfür-ilişkili modifikasyonlara ve kısmi yapısal yeniden düzenlenmeye yol açtığını göstermektedir.

Keywords

• Keratin izolasyonu
• atık saç örnekleri
• biyoteknolojik uygulamalar.

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