Preparation, Characterization, and Swelling and Drug Release Properties of a Crosslinked Chitosan-Polycaprolactone Gel

For applications in biotechnology to prepare biopolymers containing functional groups is essential. In addition, these materials have to be strong to provide physical support for practical applications. Recently, chitosan, polycaprolactone (PCL), and their various combinations were used for this purpose. In this work, we described the preparation and characterization of a new biodegradable polymeric gel containing chitosan and PCL. The gel preparation reactions were performed in suitable acetic acid solutions to obtain the products in high yields. A crosslinking agent was added to produce crosslinked gels. Swelling behavior of chitosan/PCL gels in different compositions was studied, and the results were compared. The chitosan/PCL gels show a rather large equilibrium swelling in water and in the phosphate buffered saline solution. Acrylic acid (AA) was added to these gels during preparation process to obtain a stable material for various applications. These polymeric gels were characterized by Fourier transform infrared. Their physical and morphological properties were investigated by using differential scanning calorimeter and scanning electron microscope techniques, respectively. Cell growth experiments indicate that chitosan, a positively charged polysaccharide, is not suitable for cell proliferation studies. On the other hand, the drug release studies were successful and, 59% of lidocaine, was released from a chitosan/PCL/AA hydrogel in buffer solution at pH 7.4 at 37 degrees C. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 119: 2885-2894, 201

Statik tepe boşluğu-gaz kromatografik metot kullanılarak set-tip yoğurtlarda uçucu bileşenlerin belirlenmesi

In this study, cows’ milk and aromatic cultures such as CH-1, YF-3331 and YC-350 used in production of yogurts. The volatile compounds in the samples were determined on the 1st, 7 th, 14th and 21st days of storage by using static headspace gas chromatographic method. During storage, the amount of individual volatile compounds varied significantly in yogurts depending on type of culture used. The volatile compounds acetaldehyde, acetone, ethanol, acetoin, 2-furanmethanol and ethyl phthalate were determined in all samples. On day 1, acetaldehyde (82 mg/kg) was the highest compound in yogurt made using culture CH-1 which followed by yoghurts with YC-350 (66 mg/kg) and YF-3331 (54 mg/kg). Even though the amounts of acetaldehyde and ethanol decreased at the end of storage, acetoin increased in all the samples. While the amount of acetone in yogurt made using culture CH-1 showed fluctuations during storage, its levels in yogurts with cultures YF-3331 and YC-350 steadily increased and decreased, respectively.Bu çalışmada, yoğurt üretimleri inek sütüne CH-1, YF-3331 ve YC-350 aromatik yoğurt kültürleri ilave edilerek gerçekleştirilmiştir. Uçucu bileşenler, statik tepe boşluğu metodu kullanılarak gaz kromatografisinde depolamanın 1, 7, 14 ve 21. günlerinde belirlenmiştir. Depolama süresince her bir uçucu bileşen kullanılan kültürün çeşidine bağlı olarak istatistiksel olarak önemli bir değişim göstermiştir. Uçucu bileşenlerinden, asetaldehit, aseton, etanol, asetoin, 2-furan methanol ve etil fitalat tüm örneklerde tespit edilmiştir. Depolamanın 1. gününde, CH-1 kültürü ile yapılan yoğurtta en yüksek seviyede asetaldehit (82 mg/kg ) belirlenmiş, onu YC-350 (66 mg/kg) ve YF-3331 (54 mg/kg) kültürleri ile yapılan yoğurtlar izlemiştir. Tüm örneklerde asetaldehit ve etanol depolamanın sonunda azalma göstermesine rağmen asetoin artmıştır. Asetoin miktarı, CH-1 kültürü ile yapılan yoğurtta depolama süresince dalgalanmalar göstermesine karşın, YF-3331 kültürlü yoğurtta artma ve YC-350 kültürlü yoğurtta ise azalma eğilimi göstermiştir

Surface chemistry dependent toxicity of inorganic nanostructure glycoconjugates on bacterial cells and cancer cell lines

© 2022 Elsevier B.V.Surface functionalized nanostructures have outstanding potential in biological applications owing to their target-specific design. In this study, we utilized laboratory synthesized carbohydrate-derivatives (i.e., galactose, mannose, lactose, and cellobiose derivatives) for aqueous one-pot synthesis of gold (Au) and silver (Ag) nanostructure glycoconjugates (NSs), and iron metal-organic framework glycoconjugates (FeMOFs). This work aims to test whether differences in the surface chemistry of the inorganic nanostructures play roles in revealing their toxicities towards bacterial cells and cancerous cell lines. As of the first step, biological activity of AuNSs, AgNSs, and FeMOFs were tested against a variety of gram (−) and gram (+) bacterial strains, where AgNSs possessed moderate to high antibacterial activities against all the tested bacterial strains, while AuNSs and FeMOFs showed their bacterial toxicity mostly depending on the strain. Minimum inhibitory concentration (MIC) and Minimum bactericidal concentration (MBC) determination studies were performed for the nanostructure glycoconjugates, for which μg/mL MBC values were obtained such as (Cellobiose p-aminobenzoic acid_AgNS) CBpAB_AgNS gave 50 μg/mL MBC value for P.aeruginosa and S.kentucy. The activity of selected sugar ligands and corresponding glycoconjugates were further tested on MDA-MB-231 breast cancer and A549 lung cancer cell lines, where selective anticancer activity was observed depending on the surface chemistry as well. Besides, D-penicillamine was introduced to galectin specific sugar ligand coated AuNS glycoconjugates, which showed very strong anticancer activities even at low doses. Overall, the importance of this work is that the surface chemistry of the inorganic nanostructures can be critical to reveal their toxicity towards bacterial cells and cancerous cell lines