Molecular size collagen

There are approximately 200 other proteins present in bone, though most of them are present only in trace amounts (Delmas et al., 1984 Linde et al., 1980, as cited in van Klinken, 1991). The second most common bone protein, osteocalcin, comprises 1-2 weight % of total fresh bone. Osteocalcin bonds with both the bone mineral fraction and bone collagen, but it seems to be unstable in solutions. Due to its small molecular size and strong mineral stabilization, osteocalcin can survive up to 50.000 years (C.l. Smith et al., 2005), and it may offer an alternative to the use of collagen in paleoenvironmental stable isotope research. However, osteocalcin s role and importance in this field of study has yet to be defined (Collins et al., 2002). 

As before, by dividing Pe by PABL, the transport kinetics is seen to be 32% ABL-controlled, or, upon dividing Pe by Pm the overall transport of sucrose is seen to be 51% collagen matrix-controlled by molecular size restricted diffusion. 

The use of protein hydrolysates and quaternized derivatives in shampoo formulations has been demonstrated to reduce the loss of tensile strength caused by anionic tensides on the hair fibers (124,125). This protective effect is higher for quaternized derivatives than for parent hydrolysates. A wheat protein hydrolysate was found to be more effective than a collagen hydrolysate. Since the two tested products had similar isoelectric point and average molecular size, the difference could be explained by the higher hydrophobicity of the vegetable derivative. 

Miller AT, Karmas E, Fu Lu M. Age-related changes in the collagen of bovine cotium studies on extractability, solubility and molecular size distribution. J Food Sci 1983 48 681-685. 

We next assume that the implant is 0.1 cm thick and highly porous (as would be the case for a collagen gel, for example), so that 0 = 1, with a mean pore size of >10 /xm, which is much larger than the molecular size of transported molecules, so that W = 1. Using these values, we calculate the Pdclet number and corresponding flux rate... 

Chromatographic purification of cross-links. The initial steps of the purification were to separate the cross-links from monomeric amino acids, followed by the separation of individual cross-links. The acid hydrolyzate of demineralized roof powder (13.0 g collagen) was separafed on a size exclusion column fo yield the high molecular weight fractions. 

V-1 from acid and alkaline hydrolyzates, SCX-HPLC of amino acids, a mixture of purified crosslinks and hydroxylysine b purified cross-link V-2 c amino acids from an acid hydrolyzate (6 M HCl) of reduced bovine dentin retained on a phenylboronate agarose column after purification as high molecular weight fractions by repeated size exclusion chromatography d as c, alkaline hydrolyzate (2 M KOH). Injections (c, d) resulted from 18 and 52 mg collagen originally hydrolyzed, respectively. 1 = 111 (HP) 2 = V-2 3 = IV 4 = V-1-1 (DHLNL) 5 = HLNL (bovine tendon) 6 = VI (histidinoalanine ) 7 = hydroxylysine 8 = VI (lysinoalanine). 

The proposed procedure allows a rather accurate assessment of the size and optical properties of large molecular formations. In a recent example (Shcheslavskiy et al. 2006b), we attempted to interrogate the size of molecular assemblies of collagen... 

The diffusion coefficient depends on a number of factors, including the molecular properties of solutes the structures of tissues, and temperature. The temperature-dependence is less critical for drug delivery, since the temperature in tumors is stable and close to the body temperature. The dependence of D on tissue structures is significant (Netti et al., 2000 Pluen et al., 2001). It is mediated through the size and the volume fraction of pores, the tortuosity of diffusion pathways, and the connectedness of pores (Yuan et al., 2001). Diffusion of macromolecules is faster in tissues with a lower collagen type I content (Pluen et al., 2001) or tissues treated with collagenase (Netti et al., 2000). However, there is no correlation between D and the concentration of total or sulfated glycosaminoglycans (Netti et al., 2000). 

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