Collagen sponges

Since the theory and medical applications of collagen sponge were described by Chvapil et al. (52-54), they have been used to deliver steroid hormones (55), the anticancer drugs trans-retinoic acid (TRA) (56,57), and 5-fluorouracil (5-FU) (58), and antibiotics (59). 

The uptake of TRA into cervical tissue was determined by measuring tissue radioactivity following insertion of the collagen sponge cervical cap containing tritium-labeled TRA. The TRA concentrations peaked at 4 hr and then diminished rapidly by 24 hr. Since measurements of blood samples revealed that no systemic absorption had occurred, high local concentrations over an extended period of time may be possible without systemic side effects. 

Fig. 3.25.1. Porous structure of collagen sponge produced by freezing in a cryogenic bath at -25 °C and subsequently freeze dried (scanning electron microscope, white bar = 1 mm) (from 13.67]).

Fig. 3.25.2. Porous structure of collagen sponge produced by directional solidification accord-t-UfT- to the. Power- hVxw tx. rxxeJbocI- atlcL...

Sehoof, H., Apel, J., Heschel, I., Rau, G. Influence of the freezing process on the porous structure of freeze dried collagen sponges (unpublished results, Helmholtz-Institute, Aachen, Germany... 

An ultraviolet spectroscopic method was presented, and used for the assay of procaine and nitrofural in a multicomponent collagen sponge without prior separation of the drugs [33]. Crushed Collagen Sponge (0.1 g) was dissolved in 70 mL of 1 mM HCl, and heated for ten minutes. The solution was cooled, diluted to volume, mixed, filtered, whereupon the first 20 mL was discarded. The absorbance of the analyte solution was then measured at 290 and 373 nm (against 1 mM HCl) for procaine and nitrofural, respectively. 

Geiger, M. and Freiss, W. (2002b). Collagen sponge implants. Pharm. Tech. Europe, 14(4), 58-66. 

Collagen sponges with microporous structures from tilapia were fabricated reconstituted collagen fibrils using freeze-drying and cross-linked by DHT treatment or additional treatment with WSC treatment. The pellet implantation tests into the paravertebral muscle of rabbits demonstrated that tilapia collagen caused rare inflammatory responses at 1- and... 

Manufacturing Principles of Freeze-Dried Collagen Sponges Characteristics and Applications... 

Flgu re 1 Structu re of a collagen sponge. Enlargement as seen through an eLeetioii microscope ( OOkV... 

The pro(>eri ies of a collagen sponge depejid, among other things, on... 

For a better understanding of the relation of structural and physical properties of collagen sponges and their biological reactivity, it is necessary to explain in more detail the processing methods of the raw material. 

Collagen sponges meet the specification required for an ideal hemostat ... 

In summary, collagen sponges produced in a proper way, by the method of freeze-drying, are from the toxicological-pharmacological point of view safe and effective hemostatic materials for topical hemostasis with excellent handling characteristics. 

Figure 3 TEM picluie oJ a 12-day-old wound, covered with collagen sponge. Collagen spongesinjccure, tilled witf. wound exudate, Luuiaijiing fibroblasts (F) and cplihelial cells (fi)(15tWx),...

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