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Bacterial cellulose (BC) nanofibers with high purity, high surface/volume ratio, high biocompatibility, high porosity, high tensile strength, and high water holding capacity are emerging attractive biomaterial. BC nanofibers can be prepared simply via bacterial incubation withalow cost inadetermined shape owing to its in-situ moldability. BC nanofibers due to its structural and morphological properties have demonstrated great potential asanative form or with various modifications using polymers, micro/nanoparticles, and small molecules for diverse application areas. This review aims to discuss the applicability and efficiency of the BC nanofibers and its composites focusing on the unique characteristics of BC in the fields of separation, drug delivery, wound dressing, and tissue engineering. It overviews the recent developments about the fabrication methods of BC that was used asaseparation medium, adrug delivery vehicle, awound dressing material, andascaffold.

Wound repair is a complex process that has not been entirely understood. It can conclude in several irregularities. Hence, designing an appropriate wound dressing that can accelerate the healing period is critical. Infections, a major obstacle to wound repair, cause an elevated inflammatory responses and result in ultimate outcome of incomplete and prolonged wound repair. To overcome these shortcomings, there is a growing requirement for antibacterial wound dressings. Dressings with antibacterial activities and multifunctional behaviors are highly anticipated to avoid the wound infection for successful healing. The aim of this review is not only to concentrate on the importance of antibacterial dressings for wound healing applications but also to discuss recent studies and some future perspectives about antibacterial wound dressings. WOS:000578645500001 2-s2.0-85092403055 PubMed: 33047502

In this study, we have reported a novel wastewater treatment technique by phenol imprinted bacterial cellulose (BC-MIP) nanofibers with high specificity and adsorption capacity. N-methacryloyl-(L)-amido phenylalanine (MAPA) functional monomer was used to create specific binding sites for the template molecule phenol via electrostatic and hydrophobic interactions. BC-MIP nanofibers were synthesized by surface imprinting approach in the presence of different amounts of total monomer (% weight), monomer/template ratio and polymerization time. Then, the nanofibers were characterized by FTIR-ATR, surface area analysis (BET), elemental analysis, scanning electron microscopy (SEM) and contact angle measurements. Adsorption studies were performed with respect to pH, temperature and ionic strength, and the adsorption capacity was calculated by using the spectrophotometer. In order to desorb the adsorbed phenol from BC-MIP nanofibers, 0.1 M NaCl solution was used. Besides, BC-MIP nanofibers were applied to real wastewater samples from Ergene basin in Turkey. The suitable equilibrium isotherm was determined as Langmuir isotherm. To evaluate the selectivity of the BC-MIP nanofibers, similar molecules were utilized as non-template molecules, which were 2-chlorophenol, 4-chlorophenol and 2,4-dichlorophenol. Electrostatic interactions were found to contribute to the generation of specific recognition binding sites. The results have shown that imprinting of phenol was achieved successfully with high adsorption capacity. The phenol removal efficiency was reported up to 97%. BC-MIP nanofibers were used 10 times with a negligible decrease in adsorption capacity.

WOS: 000297953800017, PubMed ID: 22052836, Molecular imprinting is an attractive biomimetic approach that creates specific recognition sites for the shape and functional group arrangement to template molecules. The purpose of this study is to prepare cytochrome c-imprinted poly(hydroxyethyl methacrylate) (PHEMA)-based supermacroporous cryogel which can be used for the separation of cytochrome c from protein mixtures. N-Methacryloyl-(L)-histidinemethylester (MAH) was used as the metal-coordinating monomer. In the first step, Cu2+ was complexed with MAH, and the cytochrome c imprinted PHEMA (MIP) cryogel was prepared by free radical cryopolymerization initiated by N,N,N',N'-tetramethylene diamine at -12 degrees C. After polymerization is completed, the template cytochrome c molecules were removed from the MIP cryogel using 0.5 M NaCl solution. The maximum cytochrome c binding amount was 126 mg/g polymer. Selective binding studies were performed in the presence of lysozyme and bovine serum albumin. The relative selectivity coefficients of MIP cryogel for cytochrome c/lysozyme and cytochrome c/bovine serum albumin were 1.7 and 5.2 times greater than those of the non-imprinted PHEMA cryogel, respectively. The selectivity of MIP cryogel for cytochrome c was also confirmed with fast protein liquid chromatography. The MIP cryogel could be used many times with no remarkable decrease in cytochrome c binding capacity.

Proteom, bir organizma ya da dokunun genomu tarafından ifade edilen proteinlere verilen addır. Proteomik olarak tanımlanan protein analizi, proteinlerin yapısal özelliklerinin belirlenmesini ve işlevlerinin aydınlatılmasını kapsar. Proteom çalışmalarında en çok çalışılan biyolojik sıvı, kan plazması ve serumdur. Kan plazması, insan vücudunda yer alan ana protein kategorilerinin büyük çoğunluğunu içermesi nedeniyle hastalıklara özgü proteinlerin belirlenmesi için ideal bir kaynaktır. Albumin ve immunoglobulinler plazma proteinlerinin % 80'ini oluştururlar ve az miktardaki diğer proteinleri maskelerler. Dolayısıyla bu proteinlerin ortamdan uzaklaştırılması sayıca daha az olan hastalık işaretçi proteinlerinin belirlenmesini kolaylaştıracaktır.Boya-ligand afinite kromatografisi, ucuz, kararlı ve grup spesifik boyaların ligand olarak kullanıldığı, protein ve enzimlerin ayrılması, saflaştırılması ve uzaklaştırılmasında kullanılan etkin ve yaygın bir yöntemdir. Özellikle albuminin uzaklaştırılması için boya-ligand Cibacron Blue F3GA ve türevleri, sıklıkla kullanılmaktadır. Bakteriyel selüloz, yüksek su tutma kapasitesi, yüksek mekaniksel dayanımı ve nanofiberlerden oluşan ağsı yapısıyla dikkat çeken biyouyumlu biyopolimerdir.Sunulan çalışmanın amacı; ucuz ve üstün özelliklere sahip bakteriyel selüloz nanofiber membranlara boya-ligand Cibacron Blue F3GA takılarak, insan plazmasındaki albumini yüksek seçicilik ve yüksek kapasiteyle uzaklaştırmak için adsorbent hazırlanmasıdır. İlk basamakta, A. xylinum bakterisi ile zamanla hücre çoğalma ve selüloz oluşumu kinetik parametreleri saptanmıştır. Daha sonra, uygun besi yeri ve koşullarında bakteriyel selüloz membranlar sentezlenmiştir. Membranların bakteriyel kültürden uzaklaştırılmalarının ardından Cibacron Blue F3GA uygun koşullarda yapıya immobilize edilmiştir. Hazırlanan Cibacron Blue F3GA takılı bakteriyel selüloz nanofiber membranlar, şişme deneyleri, elementel analiz, Fourier transform infrared spektroskopisi (FTIR) ve taramalı elektron mikroskopisi (SEM) ile karakterize edilmiştir. Cibacron Blue F3GA takılı bakteriyel selüloz nanofiber membranlar, HSA sulu çözeltisi ve insan plazmasından HSA adsorpsiyonu için kullanılmıştır. Adsorpsiyon deneyleri, farklı ortam koşullarında sürekli ve kesikli sisteminde incelenmiştir (pH, akış hızı, protein konsantrasyonu, sıcaklık, tuz etkisi). Cibacron Blue F3GA takılı bakteriyel selüloz nanofiber membranların sulu çözeltiden maksimum HSA adsorpsiyon kapasitesi, HSA derişiminin platoya ulaştığı değer olan 7 mg/mL'de, 1800 mg/g olarak bulunmuştur. Sulu çözelti ve insan plazmasından maksimum adsorpsiyon oranları sırasıyla %5 ve %40'tır. HSA' nın saflığı elektroforez ile belirlenmiştir. 10 kez tekrarlanan adsorpsiyon-desorpsiyon döngüsü sonucunda adsorpsiyon kapasitesinde önemli bir değişim olmadığı gözlemlenmiştir. Proteome is the set of expressed proteins by the genome of organism or tissue. Proteomics is the analysis of proteins, particularly their structures and functions. Human blood plasma is possibly the most important proteome from a clinical/medical point of view. A broad inventory of plasma proteins (both qualitative and quantitative) provides diagnosis and development of new therapeutic products. It might be expected that if plasma or serum is selectively depleted of albumin, this would facilitate the analysis of proteins present at low concentration.Dye-ligand chromatography has played an important role in the separation, purification and recovery of proteins and enzymes. Dye-ligands are inexpensive, stable and group specific. Especially for the depletion of albumin, Cibacron Blue and derivatives are frequently used. Bacterial cellulose is a natural biopolymer with its high hyrophilicity, high mechanical strength and ultrafine network structure.The submitted study is dedicated to develop specific adsorbents for the removal of albumin from human plasma with high selectivity and high capacity with bacterial cellulose via coupling Cibacron Blue F3GA. In the first step, kinetic parameters of A. xylinum of bacterial growth and cellulose formation was determined. Bacterial cellulose was synthesized in static conditions in the appropriate culture medium. After the purification of the membranes, dye-ligand Cibacron Blue F3GA was immobilized to the membranes. Cibacron Blue F3GA immobilized bacterial cellulose membranes were characterized by means of swelling studies, elemental analysis, Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscope (SEM). These polymers were used for the adsorption of albumin from the aqueous solution of HSA and human plasma. Adsorption experiments were investigated under different conditions in a batch and continuous system (i.e., medium pH, flow rate, protein concentration, temperature, ionic strength). The maximum adsorption capacity of Cibacron Blue F3GA immobilized bacterial cellulose membranes from aqueous HSA solution was 1800 mg/g when plateau value of HSA concentration is 7 mg/mL. Percentage of albumin removal from aqueous solution and human plasma is respectively 5% and 40%. Purity of HSA was estimated by using SDS-PAGE.It was observed that after 10 adsorption-desorption cycle, Cibacron Blue F3GA immobilized bacterial cellulose membranes can be used without significant loss in HSA adsorption capacity. 87

P oly vinyl alcohol PVA -based hydrogels prepared using freeze/thawing treatment have become increasingly important biomaterials for biomedical applications having great properties such as biocompatibility, biodegradability and high water absorbency. In this study, PVA-based physically cross-linked hydrogels were prepared with and without the presence of poly ethylene glycol PEG freezing at -16 °C for 16 h and thawing at room temperature for 8 h. The focus of this work was to address the effect of the addition of PEG Mw: 2000 or 5000 and the effect of the number of freezing/thawing cycles on swelling behaviour. The Scanning Electron Microscopy SEM measurements demonstrated the morphological characteristics of PVA-based hydrogels indicating the formation of the macroporosity fabricated during freeze/thawing process. From the swelling tests undertaken it w as apparent that all the hydrogels exhibited unique swelling characteristics having high swelling degree at all pH values such as pH 2.1, 5.5 and 7.4 representing the pH values of stomach, blood and dermis. Thus, the hydrogels synthesized in this study present important potential for biomedical applications

The antibacterial sponges with high macroporosity, high interconnectivity and high biocompatibility is a significant concern for wound healing applications. In this work, novel Aloe vera (AV) based sponges were developed via subsequent lyophilization with further chemical crosslinking throughout the double network sponges. Single network was composed of gelatin-sodium alginate (G-SA) while the double network using gelatin-sodium alginate- sodium hyaluronate (G-SA-HA) was produced with the addition of hyaluronic acid solution into the gelatin-sodium alginate matrix. Lastly, Aloe vera as the bioactive agent was fabricated throughout the gelatin-sodium alginate-sodium hyaluronate matrix. The AV-based sponges demonstrated large pores with high interconnectivity. The swelling degree of the AV-based sponges were higher than that of G-SA and G-SA-HA sponges. The release of AV from the sponges reached an equilibrium value after 24 h showing a more controlled release at pH 5.5 than at pH 7.4. AV-based sponges showed antibacterial activity against Staphylococcus aureus, Enterococcus faecalis, Streptococcus pneumoniae and Bacillus cereus and displayed any cytotoxicity against Mesenchymal stem cells. Scientific Projects Coordination Unit of Hitit UniversityHitit University [MUH19001.18.001]; Hitit University Scientific and Tecnical Application and Research Center The financial support from the Scientific Projects Coordination Unit of Hitit University under the project number MUH19001.18.001 is gratefully acknowledged. The authors are also greateful to the support of Hitit University Scientific and Tecnical Application and Research Center. WOS:000608662700001 2-s2.0-85100181974

Bilayer wound dressing systems consisting of various biopolymers have been preferred in biomedical applications due to its enhanced advantages in comparison with conventional systems. The aim of this research was to develop a novel bilayer wound dressing based on gelatin (G) and gellan gum (GG). The bilayer was composed of an upper layer impregnated with antibiotic drug sodium ampicillin and a drug-free lower sponge layer. The bilayer hydrogels were characterized by FTIR, TGA, DSC and SEM analyses including swelling behaviors and hydrolytic degradation tests. To achieve faster healing of the wound by prevention of the bacterial infection, the bilayer hydrogels were developed as antibiotic-releasing vehicles. Herein, release study of sodium ampicillin was performed in PBS to simulate the physiological micro-environment. Additionally, cyto-compatibility tests of L929 fibroblast cells showed the high proliferation and survival through drug-loaded GG and G hydrogels (GG-G-D) after 24h, 48h and 72h incubation. This novel GG-G bilayer hydrogel could be a good candidate as wound dressing. Scientific Projects Coordination Unit of Hitit UniversityHitit University [MUH19001.19.004] The financial support from the Scientific Projects Coordination Unit of Hitit University under the project number MUH19001.19.004 is gratefully acknowledged. WOS:000685014000001 2-s2.0-85112551430

The development of chitosan-gelatin (CS-G) hydrogels embedded with ampicillin-loaded hyaluronic acid nanoparticles (HA-NPs) for wound dressing is proposed. It was aimed to provide controlled ampicillin delivery by incorporation of HA-NPs into biocompatible CS-G hydrogel structure. According to in vitro ampicillin release studies, 55% of ampicillin was released from CS-G/HA-NPs hydrogels after 5 days. Antibacterial performance of CS-G/HA-NPs hydrogels was proven with agar disc diffusion test. For cytotoxicity assay, fibroblast cell viability increased in CS-G/HA-NPs hydrogels compared with CS-G group after 24 hr incubation. Consequently, the potential ability of CS-G/HA-NPs hydrogels as a controlled drug delivery system has been verified. Hitit University Scientific and Technical Application and Research Center The authors are grateful to the support of Hitit University Scientific and Technical Application and Research Center. WOS:000574568700001 2-s2.0-85091851085 PubMed: 33009868