http://experimentationlab.berkeley.edu/sites/default/files/AFMImages/butt_AFM.pdf

Force measurements with the atomic force microscope: Technique, interpretation and applications

Characterization and Distribution of Water-repellent, Self-cleaning Plant Surfaces

For the synthesis of hydroxyapatite crystals from aqueous solutions three preparation methods were employed. From the experimental processes and the characterization of the crystals it was concluded that aging and precipitation kinetics are critical for the purity of the product and its crystallographic characteristics. The authentication details are presented along with the results from infrared spectroscopy, X-ray powder diffraction, Raman spectroscopy, transmission and scanning electron photographs, and chemical analysis. Analytical data for several calcium phosphates were collected from the literature, extensively reviewed, and the results were grouped and presented in tables to provide comparison with the data obtained here.

Synthesis and characterization of hydroxyapatite crystals: A review study on the analytical methods

Structure and reactivity of water at biomaterial surfaces

Physical and chemical properties of a new root-end filling material.

An experimental technique is described to determine contact angles on bacterial layers deposited on cellulose triacetate filters. Measurements with water, water-n-propanol mixtures, and alpha-bromonaphthalene were employed to calculate surface free energies of various oral bacteria. Differences of 30 to 40 erg cm-2 were obtained for four different bacterial species isolated from the human oral cavity, if the concept of dispersion and polar surface free energies is applied. The free energies obtained were used to calculate interfacial free energies of adhesion of these bacteria from saliva onto tooth surfaces. Bacterial adhesion is energetically unfavorable, if the enamel surface free energy is less than 50 erg cm-2.

Measurement of the surface free energy of bacterial cell surfaces and its relevance for adhesion.

Orthodontic appliances and enamel demineralization: Part 1. Lesion development

The effect of surface roughening of polymers on measured contact angles of liquids

A direct comparison of quantitative microradiography and microhardness profiles was made using artificial caries-like lesions in human enamel. Tooth crowns with lesions were cut in half through the ce

Comparison of artificial caries-like lesions by quantitative microradiography and microhardness profiles

To determine whether the surface free energy of polymer materials influences the spreading of 13 polymers and glass were related to spreading and growth of human skin fibroblasts. Experiments were performed in both the presence and absence of serum proteins. We calculated the surface free energy from contact angles of phosphate-buffered saline (PBS), n-propanol/PBS mixtures, and alpha-bromonaphthalene on the polymers, using the concept of polar and dispersion components accounting for spreading pressures. Cell spreading and substratum surface free energy (gamma s) showed a characteristic sigmoid relationship both in the presence and in the absence of serum proteins; good spreading only occurred when gamma s was higher than approximately 57 erg . cm-2. In the presence of serum proteins, cell spreading is similar on most materials; only few materials show relatively high cell spreading. Cell growth in the presence of serum proteins did not differ significantly on the various polymers with reference to their gamma s values. In contrast, two groups of polymers could be distinguished in the absence of serum with respect to cell growth. The first group showed increasing cell growth with increasing gamma s, whereas the second group showed consistently low cell growth. The results demonstrate the complex relationship between cell spreading and substratum surface free energy as well as the role of serum proteins in modifying the surface characteristics of polymers in relation to cell spreading and growth.

J. Arends

Papers

Measurement of the surface free energy of bacterial cell surfaces and its relevance for adhesion.

Orthodontic appliances and enamel demineralization: Part 1. Lesion development

The effect of surface roughening of polymers on measured contact angles of liquids

Comparison of artificial caries-like lesions by quantitative microradiography and microhardness profiles

The influence of substratum surface free energy on growth and spreading of human fibroblasts in the presence and absence of serum proteins