Matrix assembly, polymer surfaces

The formation of fibronectin fibrils, another relatively well-studied supramolecular structure of ECM polymers, was extensively studied in vitro as well. Many different cell types synthesize fibronectin and secrete it as a disulfide-bonded dimer composed of 230-270 kDa subunits. Each subunit contains three types of repeating modules, types I, II, and III. These modules comprise functional domains that mediate interactions with other ECM components, with cell surface receptors and with fibronectin itself. Fibronectin matrix assembly involves binding domains and repeating modules from all regions of fibronectin which participate in interactions with cell surface receptors and with other fibronectin molecules. Newly secreted fi-... 

For consistent and reproducible operation it is important to control chemosensor features like thickness of the MIP coatings. Generally, MIPs were prepared and immobilized on PZ resonators by using two distinct procedures, namely in situ assembling on the resonator surface [103] or physical entrapment of the preprepared MIP particles in an inert polymer matrix attached to this surface [21]. Typically, thickness of the polymer is 20 nm to 5 pm. In situ immobilization of MIPs (see below in Sects. 3.2.1-3.2.4) can be accomplished by surface grafting, sandwich casting, electropolymerization, physical entrapment or chemical coupling [102],... 

MIP beads or microspheres are also widely used for sensing purposes [166]. They are prepared by precipitation polymerization and then they are embedded in a dedicated matrix, which is immobilized on the transducer surface. Moreover, the MIP beads are used to serve as stationary phases in HPLC [167] and for catalytic purposes. Other systems, such as self-assembled monolayers, SAMs [168], sol-gel matrices [169] and preformed polymers [170] have also been utilized for fabrication of MIP constructs. 

In a subsequent study, the Co coordinated assembly was grafted onto a cross-linked poly(glycidoxypropylmethacrylate) (GMA)-ethylene glycol dimethacrylate (EDMA) support surface. The template and Co ions were then leached out from the matrix. This surface grafted polymer exhibited turnover, Michaelis-Menten kinetics and mechanisms such as inhibition by tosyl phenyl alanyl chloromethyl ketone and inhibition on acetylation of hydroxyl group of 2-hydroxyethylmethacry-late (HEMA), similar to native chymotrypsin. 

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