Attachment and Proliferation of Osteoblasts on Lithium-Hydroxyapatite Composites

The biocompatibility and bioactivity properties of hydroxyapatites (HAs) modified through lithium addition were investigated. Hydroxyapatites obtained from bovine bone were mixed with lithium carbonate (Li), in the proportions of 0.25, 0.50, 1.00, and 2.00% wt, and sintered at 900°, 1000°, 1100°, 1200°, and 1300°C, creating LiHA samples. The osteoblast culture behavior was assessed in the presence of these LiHA compositions. The cellular interactions were analyzed by evaluating the viability and cellular proliferation, ALP production and collagen secretion. The cytotoxic potential was investigated through measurement of apoptosis and necrosis induction. The process of cellular attachment in the presence of the product of dissolution of LiHA, was evaluated trough fluorescence analysis. The physical characteristics of these materials and their cellular interactions were examined with SEM and EDS. The results of this study indicate that the LiHA ceramics are biocompatible and have variable bioactivities, which can be tailored by different combinations of the concentration of lithium carbonate and the sintering temperature. Our findings suggest that LiHA 0.25% wt, sintered at 1300°C, combines the necessary physical and structural qualities with favorable biocompatibility characteristics, achieving a bioactivity that seems to be adequate for use as a bone implant material

Sol-jel yöntemiyle üretilmiş alümina-bovine hidroksiapatit kompozit tozlarının karakterizasyonu

Alümina ve hidroksiapatitin biyomalzeme olarak kullanıldığı bilinmektedir. Alüminanın mukavemeti yüksektir ancak biyoinert bir malzeme olduğu için vücut dokularına bağlanma yeteneği zayıftır. Hidroksiapatit ise vücut dokularıyla birleşme konusunda iyi bir biyoaktif malzeme olmasına rağmen gevrek yapısı nedeniyle kırılgan niteliktedir. Alümina ve hidroksiapatit, kompozit oluşturmak üzere bir araya getirildiklerinde daha fonksiyonel bir yapının sağlanacağı düşünülmektedir. Bu çalışmada; sol-jel yöntemi kullanılarak alüminyum izopropoksit (AIP) başlangıç maddesinden ilk olarak böhmitik (AlOOH) sol elde edilmiştir. Ardından böhmitik sol içerisine ağ-% 20 oranında bovine hidroksiapatit (BHA) tozları ilave edilerek mekanik olarak karıştırılmış ve elde edilen kompozit karışımı, 110 ºC’de 3 saat boyunca jelleştirilmiştir. Jel haline gelen kompozit karışımı sırasıyla; 500, 800, 1000 ve 1300 ºC olmak üzere 4 farklı sıcaklıkta ısıl işleme tabi tutulmuştur. Isıl işlemler sonrasında, elde edilen kompozit karışım tozlarına XRD, DTA-TGA ve SEM-EDS karakterizasyon analizleri uygulanmıştır

ZnO applications and challenges

Metal oxide nanoparticles represent a new class of important materials that are increasingly being developed for use in research and health-related applications. Although the in vitro antibacterial activity of zinc oxides and some other zinc compounds has been known for quite some time, only in the last few years nanoparticles of ZnO have been investigated for their antibacterial activity, the knowledge about it remaining deficient. The antimicrobial activity of ZnO nanoparticles is strongly influenced by some factors such as size and the presence of light. The potential applications include, but are not limited to, topic drugs, cosmetics or component for agents that control the spread of bacterial strains (antibacterial paint in hospitals, antibacterial coatings for fabrics, antibacterial packaging for food, etc). The current review aims to present the level of knowledge accumulated on the antibacterial and antifungal activity of ZnO. © 2014 Bentham Science Publishers

Biodegradable Indocyanine Green Nanoprobe for In vitro Early Tumor Diagnosis

Advanced biomedical imaging techniques, intelligent drug designs and controlled drug release studies let patients can be safeguarded via early detection of cancerous cells without damaged to healthy cells. In this study, the ICG nanoprobe was fabicated via co-axial electrospinning method by encapsulating of ICG, which has high light absorption and emission in the near infrared region (NIR), in biocompatible and biocompatible Poly(epsilon-caprolactone) (PCL) polymer. During co-axial fiber formation, in order to understand of the physical effect of ICG solution onto pure PCL solution, viscocity, electrical conductivity, density and surface tension were characterized before co-axial electrospinning process. The high electrical conductivity and low viscosity of ICG, caused the PCL/ICG nanofiber diameters (Phi=627.15 +/- 157.77 nm) decreased compared to pure PCL nanofibers (Phi)=930.71 +/- 210.27 nm). Encapsulated ICG dye in the PCL nanofiber was determined by FT-IR and confocal microscopy. Controlled ICG release from PCL / ICG nanofibers was performed up to 21 days in PBS (pH 7)