Hydrophilic affinity

Y. Wada, M. Tajiri, and S. Yoshida, Hydrophilic affinity isolation and MALDI multiple-stage tandem mass spectrometry of glycopeptides for glycoproteomics, Anal. Chem., 76 (2004) 6560-6565. 

The steps involved in this method are as follows (l)The template materials are highly ordered two-dimensional hexagonal mesoporous silica such as SBA-15 and three-dimensional caged mesoporous silica. (2) Metal precursors are introduced by capillary force, chelation force, and hydrophilic affinity. (3) A thermal treatment is employed to crystallise the guest materials and to form the mesoporous pattern. (4) The template silica is etched by HF or NaOH to obtain self-standing ordered metal oxide guest frameworks with mesostructure. 

There is some debate about the affinity of proteins to hydrophobic surfaces. Some authors sustain the hydrophobic affinity theory [36], while others prefer the hydrophilic affinity theory [37]. The results obtained from studies carried out with culture medium supplemented with 10% fetal calf serum (PCS) suggested that the complex mixture of proteins present in PCS presented a higher affinity for the hydrophiUc surfaces. Furthermore, the Wa values suggested that the mixture of proteins adsorbed better on hydrophiUc surfaces, though the type of protein and their adsorption speed onto the surfaces is still unknown. However, the use of dynamic contact angle techniques (as has been confirmed with other materials) could help identify the velocity of adsorption and the munber of steps of adsorption, desorption, and/or ad-sorption/desorption that lead to the final interaction between the substrate and the proteins in the culture medium (Fig. 4). The contact angles obtained for the two different fluids are shown in Table 5. 

Hydrophilic Affinity to water, and aqueous solutions (i.e., brines, geothermal fluids)... 

The process of peptide synthesis involves the general concepts of antigenicity, hydrophilicity, and surface probability, as well as flexibUity indexes. The process involves an analysis of the peptide s characteristics, the use of software and databases to determine hydrophilicity (affinity for water), study of the... 

Possibility of changing the properties of micellar phases by electrolyte inclusions was shown. Under this condition, in the systems with manifestation of complexes formation between the cationic compound of the electrolyte and the polyoxyethylene chain of the surfactant, increase of the hydrophilic properties of micellar phases was observed. The electrolytes that do not have affinity to the surfactant s molecule practically do not influence the liophily of the nonionic surfactant-rich phases. 

Hydrophilic Having an affinity for water and aqueous solutions. 

For Yiv > YPv> where y v and Ypv are the surface tensions of liquid and protein, respectively, AFads increases with increasing ysv, predicting decreasing polymer adsorption. An example of this is phosphate buffer saline where y]v = 72.9 mJ/m2 and Ypv is usually between 65 and 70mJ/m2 for most proteins [5]. Therefore, supports for gel-permeation and affinity chromatography should be as hydrophilic as possible in order to minimize undesirable adsorption effects. 

The GA is a heterogeneous material having both hydrophilic and hydrophobic affinities. GA physicochemical responses can be handled depending on the balance of hydrophilic and hydrophobic interactions. GA functional properties are closely related to its structure, which determines, for example, solubility, viscosity, degree of interaction with water and oil in an emulsion, microencapsulation ability, among others. 

The preferred choice of a water-selective membrane up to now has been hydrophilic membranes because of their high water affinity. However, recently Kuhn et al. reported an all-silica DDR membrane for dehydration of ethanol and methanol with high fluxes (up to 20kg m h ) and high selectivities (H20/ethanol 1500 and H20/methanol 70 at 373 K) in pervaporation operation. The separation is based on molecular sieving with water fluxes comparable to well-performing hydrophilic membranes [51]. 

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