1: Magnetic Particles: Preparation, Properties and Applications: M. Ozaki. 2: Maghemite (gamma-Fe2O3): A Versatile Magnetic Colloidal Material C.J. Serna, M.P. Morales. 3: Dynamics of Adsorption and Oxidation of Organic Molecules on Illuminated Titanium Dioxide Particles Immersed in Water M.A. Blesa, R.J. Candal, S.A. Bilmes. 4: Colloidal Aggregation in Two-Dimensions A. Moncho-Jorda, F. Martinez-Lopez, M.A. Cabrerizo-Vilchez, R. Hidalgo Alvarez, M. Quesada-PMerez. 5: Kinetics of Particle and Protein Adsorption Z. Adamczyk.

Surface and Colloid Science

http://pharmaquest.weebly.com/uploads/9/9/4/2/9942916/superparamagnetic_iron_oxide_nanoparticles_spions.pdf

Superparamagnetic iron oxide nanoparticles (SPIONs): Development, surface modification and applications in chemotherapy

Biomimetic electrospun nanofibrous structures for tissue engineering

The effect of substrate stiffness on adult neural stem cell behavior

Among the numerous attempts to integrate tissue engineering concepts into strategies to repair nearly all parts of the body, neuronal repair stands out. This is partially due to the complexity of the nervous anatomical system, its functioning and the inefficiency of conventional repair approaches, which are based on single components of either biomaterials or cells alone. Electrical stimulation has been shown to enhance the nerve regeneration process and this consequently makes the use of electrically conductive polymers very attractive for the construction of scaffolds for nerve tissue engineering. In this review, by taking into consideration the electrical properties of nerve cells and the effect of electrical stimulation on nerve cells, we discuss the most commonly utilized conductive polymers, polypyrrole (PPy) and polyaniline (PANI), along with their design and modifications, thus making them suitable scaffolds for nerve tissue engineering. Other electrospun, composite, conductive scaffolds, such as PANI/gelatin and PPy/poly(e-caprolactone), with or without electrical stimulation, are also discussed. Different procedures of electrical stimulation which have been used in tissue engineering, with examples on their specific applications in tissue engineering, are also discussed.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/term.383

Application of conductive polymers, scaffolds and electrical stimulation for nerve tissue engineering.

https://ideaexchange.uakron.edu/cgi/viewcontent.cgi?article=1134&context=chemengin_ideas

Promoting neuron adhesion and growth

Nerve fibres are guided to their targets by the combined actions of chemotactic and haptotactic stimuli; however, translating these stimuli to a scaffold that will promote nerve regeneration is nontrivial. In pursuit of this goal, we synthesized and characterized cell-adhesive, bio- degradable chitosan scaffolds. Chitosan amine groups were reacted with methacrylic anhydride resulting in a water soluble methacrylamide chitosan (MC) that was then crosslinked by radical polymerization resulting in a scaf- fold. Biodegradability by lysozyme and penetrability of the scaffold by rat superior cervical ganglion (SCG) neurons were studied. Maleimide-terminated cell adhesive pepti- des, mi-GDPGYIGSR and mi-GQASSIKVAV, were coupled to a thiolated form of MC to promote cell adhesion. The MC scaffold was found to be porous, biodegradable, and to allow neurite penetration. Interestingly, all of these properties were found to depend upon the amount of initiator used in cross- linking. Covalent modification of the MC scaffold with cell adhesive peptides significantly improved neuronal adhesion and neurite outgrowth. The MC can be crosslinked to form a novel scaffold, where our results demonstrate its suitability in neural tissue engineering and its potential for other engi- neered tissues, such as cartilage repair, where chitosan has already demonstrated some utility. 2007 Wiley Periodicals, Inc. J Biomed Mater Res 82A: 243-255, 2007

Peptide surface modification of methacrylamide chitosan for neural tissue engineering applications.

Dynamic cycling contact angle (DCCA) measurements of six liquids from two homologous series (i.e., alkanes and alcohols) on FC-732-coated silicon wafer surfaces were performed using automated axisymmetric drop shape analysis-profile (ADSA-P). Unlike the previous one-cycle measurements that have been made in a number of studies, these cycling contact angle measurements provide more information on the mechanisms of contact angle hysteresis θhyst. Both the advancing contact angles θa (except for the one measured from the first cycle) and the receding contact angles θr obtained from different cycles were found to be time-dependent. By comparing the results between cycles, were obtained θa and θr values at some specific drop radii. It was found that both θa and θr decreased with increasing number of cycles. Furthermore, both θa and θr values obtained at the larger contact radius were larger than those obtained at the smaller radius. The result is plausible in terms of liquid sorption and/or retention by the solid surface: the solid surface modification by the liquid increases with longer solid/liquid contact, leading to smaller values of θa and θr. It was also found that contact angle hysteresis θhyst, the difference between θa and θr at each radius, increased initially and then leveled off with increasing number of cycles. The result suggests that processes which occurred on the polymer surface during the experiment, such as liquid sorption and evaporation, will eventually approach a steady state and hence lead to constant hysteresis of the contact angle. This supports the contention that liquid sorption and/or retention is a likely cause of the time dependence of contact angle hysteresis (as well as advancing and receding contact angles). All θa data obtained beyond the first cycle and all θr data reflect liquid sorption and/or retention by the solid and are therefore not a property of the solid alone. Therefore, only θa obtained in the first cycle (on the dry solid) should be used in the calculation of the surface energetics of solids.

Dynamic Cycling Contact Angle Measurements: Study of Advancing and Receding Contact Angles

Existing methodology for surface tension measurements based on drop shapes suffers from the shortcoming that it is not capable to function at very low surface tension if the liquid dispersion is opaque, such as therapeutic lung surfactants at clinically relevant concentrations. The novel configuration proposed here removes the two big restrictions, i.e., the film leakage problem that is encountered with such methods as the pulsating bubble surfactometer as well as the pendant drop arrangement, and the problem of the opaqueness of the liquid, as in the original captive bubble arrangement. A sharp knife edge is the key design feature in the constrained sessile drop that avoids film leakage at low surface tension. The use of the constrained sessile drop configuration in conjunction with axisymmetric drop shape analysis to measure surface tension allows complete automation of the setup. Dynamic studies with lung surfactant can be performed readily by changing the volume of a sessile drop, and thus the surface area, by means of a motor-driven syringe. To illustrate the validity of using this configuration, experiments were performed using an exogenous lung surfactant preparation, bovine lipid extract surfactant (BLES) at 5.0 mg/ml. A comparison of results obtained for BLES at low concentration between the constrained sessile drop and captive bubble arrangement shows excellent agreement between the two approaches. When the surface area of the BLES film (0.5 mg/ml) was compressed by about the same amount in both systems, the minimum surface tensions attained were identical within the 95% confidence limits.

Laura M.Y. Yu

Papers

Promoting neuron adhesion and growth

Peptide surface modification of methacrylamide chitosan for neural tissue engineering applications.

Dynamic Cycling Contact Angle Measurements: Study of Advancing and Receding Contact Angles

Constrained sessile drop as a new configuration to measure low surface tension in lung surfactant systems.

Poly(ethylene glycol) enhances the surface activity of a pulmonary surfactant.