Recent molecular simulations and force field development have indicated that computational methods can offer significant insight into the behavior of surfaces, polyethoxy and polysilicone systems, hydrogen bonding, solvent-water interactions, and alkane properties. Of particular interest are several studies which treat mixing thermodynamically, as well as those discussing the source of the hydrophobic effect. According to market evaluation firm Transparency Market Research, the “specialty surfactants industry is expected to reach USD 29.2 Billion Globally in 2017”. Furthermore, Transparency indicates that until at least that time nonionic surfactants, which are solubilized in alcohol co-solvated systems, are expected to be the fastest growing of all surfactant classes.
In the last decades, many studies have been developed in order to clarify the effects of calcium substitution by metals that enhance bone regeneration as was already observed for Zn2+ and Sr2+. The effect of strontium on bone is likely related to its similarity to calcium, a mineral with a known biological value. Strontium is structurally similar to calcium and can replace calcium in the bone mineral matrix. A key difference is that calcium (as an essential nutrient) is homeostatically controlled while strontium is not. In vitro cellular response of hydroxyapatite doped with strontium samples showed that the Sr incorporation by HA increased the rate of proliferation and osteoblasts cells differentiation, enhancing the ceramics functionality for osteoporosis treatment.
Multifunctional Nanoplatform for Targeted Laser-induced Hyperthermia and Microscopy of Breast Cancer Cells using SPION-based Gold and Folic Acid Conjugated Nano dendrimers: An in vitro Assay
The use of nanotechnology seems to be a promising approach for early detection, imaging and therapy of cancer. In this investigation, 9 nm superparamagnetic iron oxide nanoparticles (SPION) were synthesized and functionalized by third generation polyamidoamine (G3-PAMAM) dendrimer. The magneto dendrimer samples were then conjugated by folic acid molecules for targeting and by gold nanoparticles for photothermal hyperthermia purpose. The gold nanoparticles were synthesized using three reducing agents of sodium borohydride, hydrazine sulfate and pre synthesized 10-nm AuNPs.
The final nanocomposite is named IDAF NC (Iron oxide-Dendrimer-Gold-Folic acid). Two breast cancer cell lines of MDA MB 231 and MCF 7 were used for cytotoxicity, uptake and photothermal assay. The results confirmed that AuNPs prepared by sodium borohydride and the pre-synthesized 10-nm AuNPs were larger and those prepared by hydrazine sulfate were smaller and uniformly entrapped within dendrimer cavities. The MDA MB 231-IDAF-Hydr combination exhibited the highest viability percentage at 50 μg/mL before laser irradiation and lowest cancer cell viability of 65% (i.e., highest cell apoptosis and crystallization after irradiation).
The basis of the quantitative conical/pyramidal (nano) indentation, without fittings, iterations, or simulations, is the physically founded FN=k h3/2 relation. The constant k (penetration resistance, mN/μm3/2) from linear plot with excellent regression discards initial surface effects, identifies important phase transformation onsets, conversion and activation energies, and reveals errors.
The failing Sneddon theory of ISO with unphysical exponent 2 on h lacks these possibilities, disregards shear-force work, and violates the first energy law since 50 years. The denied but strictly quantified loss of energy (20% for physical h3/2; 33.33% at believed h2) violates the first energy law and disregards the force remaining for penetration. Straightforward correction is performed for the dimensions, by replacing unphysical exponent 2.
Understanding of interactions between cells and biomaterials is a huge parameter for improving tissue engineering and regenerative medical fields. Many different materials have already been tested (including calcium phosphate ceramics) and it has been established that surface characteristic is a parameter that influences cell responses.
The aim of this work was to characterize calcium phosphate discs containing various ratios of HA/?-TCP and specific microstructure. First results show that chemical composition and compression parameters modify surface materials. Secondly, cells were cultured (osteoblast-like cells MC3T3- E1) and morphology, viability, and differentiation were studied. SEM observations, mitochondrial (MTS assay), and alkaline phosphatase activity (ALP) measurements showed that osteoblasts have better viability and a higher rate of differentiation when cultured on dense surface compared to porous surface. The aim of this experiment was to contribute to the knowledge of interactions between osteoblast-like cells and microstructured calcium phosphate bioceramics pellets.