Albuminous material

A crude process of extraction of urushiol from the tree Rhus vernicifera was used by the Chinese during the Chou dynasty of 1122-249 BC, and the process was systematised by the Japanese. The tree is tapped at about the 10th year of cultivation by a lateral sloping incision into the bark during June to September. The sap is white to grayish in color, but on exposure to air turns yellow-brown and then black. The crude sap contains approximately 70% urushiol, 4% gum, 2% albuminous materials, and 24% water. It is stirred and filtered and heated to reduce the moisture level [138] and finally stored in air-tight containers. 

Simulated use tests involve deliberate contamination of instruments, inanimate surfaces, or even skin surfaces, with a microbial suspension. This may either be under clean conditions or may utilize a diluent containing organic (e.g. albumin) material—dirty condition. After being left to dry, the contaminated surface is exposed to the test disinfectant for an appropriate time interval. The microbes are then removed (e.g. by rubbing with a sterile swab), resuspended in suitable neutralizing medium, and assessed for viability as for suspension tests. New products are often compared with a known comparator compound (e.g. 1 minute application of 60% v/v 2-propanol for hand disinfection products— see EN1500) to show increased efficacy of the novel product. 

After settling, the juice, which is still turbid and has an acid reaction, is drawn into mixing tanks and treated with enough lime to make it slightly alkaline. This treatment results in the precipitation of a number of impurities. The limed juice is heated, and in about an hour albuminous material coagulates on the lime precipitate forming a crust, and the whole produces a thick scum. 

Lead was still being used medically and in the early part of the nineteenth century for its action on the blood. Salts of lead were found to be haemostatic and were used for the treatment of ulcers because of their ability to coagulate albuminous material. Until recently, lead compounds could be found in the British Pharmacopoea, including lead and opium solution (a mixture of Goulard s water and laudanum) and Diachylon plasters, which use lead oxide as a base. However, the 1980 B.P. does not list any lead or lead-containing preparations. 

Aldehyde treatment was necessary to enchance the thrombo-resistance of the natural rubber mixed with albumin. Material made from natural rubber mixed with albumin did not show any enchanced thromboresistance without the aldehyde treatment. 

Lipoproteins may denature on heating and if present during pasteurization can result in the formation of haze or turbidity in the final product. This material was removed traditionally by filtration through asbestos (qv) sheets (6) however, health hazards associated with asbestos have led to its replacement by alternative filter materials (23,37,193). These media have been less effective than asbestos and further measures have been required to ensure the visual clarity of albumin products, eg, further filtration developments for Hpid removal (194), preferential denaturation of contaminants using in-process heat treatment, and anion-exchange chromatography (49). 

Poly-L-lysine-blended chitosan, collagen-blended chitosan and albumin-blended chitosan were also considered, with collagen control material. Culture of PC12 cells and fetal mouse cerebral cortex cells on these biomaterials was used to evaluate their nerve cell affinity. The composite materials, had significantly improved nerve cell affinity compared to chitosan. Poly-L-lysine-blended chitosan exhibited the best nerve cell affinity and was a better material in promoting neurite outgrowth than collagen [328]. 

A unique method of formulating delivery systems based on starch/ PLA systems was studied (138). In that approach, the goal was to provide a better matrix for delivery of high molecular weight hydrophilic molecules. A hydrophilic material, starch, was combined through graft polymerization to PLA. The carbolactic polymers were then used to entrap bovine serum albumin in microspheres. 

Table 50-2 summarizes the functions of many of the plasma proteins. The remainder of the material in this chapter presents basic information regarding selected plasma proteins albumin, haptoglobin, transferrin, ceruloplasmin, aj-antitrypsin, aj i roglobulin, the immunoglobulins, and the complement system. The lipoproteins are discussed in Chapter 25. 

The cross-linking method relies on bifimctional reagents to form intermolecular linkages between the enzyme molecules to render them insoluble. Often albumin is added as an extender and glutaraldehyde is most commonly employed. This material can then be either formed as a free standing membrane or applied to the inner surface of the dialysis membrane... 

Materials. Microspherical PGG glucan (Adjuvax, Alpha-Beta Technology, Worcester, MA) was prepared from Saccharomyces cereviseae strain R4 cells (11). Zymosan, cytochrome c (cyt c), bovine serum albumin (BSA), yeast alcohol dehydrogenase (ADH), Complete Freunds Adjuvant (CFA) and Incomplete Freunds Adjuvant (IFA) were purchased from Sigma Chemical Co. (St. Louis, MO). 

Human serum albumin (HSA) may be used as a protectant against adsorptive loss of proteins present at low concentrations. HSA is present at higher concentration than the active substance and is preferentially adsorbed, coating the surface of interest and preventing adsorption of the drug. For example, insulin is subject to adsorptive loss to hydrophobic materials. Addition of 0.1-1.0% HSA has been reported to prevent this adsorptive loss [9],... 

Preparation of nanoparticles can be by a variety of different ways. The most important and frequently used is emulsion polymerization others include interfacial polymerization, solvent evaporation, and desolvation of natural proteins. The materials used to prepare nanoparticles are also numerous, but most commonly they are polymers such as poly-alklcyanoacrylate, polymethylmethacrylate, poly-butylcyanoacrylate, or are albumin or gelatin. Distribution patterns of the particles in the body can vary depending on their size, composition, and surface charge [83-85]. In particular, nanoparticles of polycyanoacrylate have been found to accumulate in certain tumors [86,87]. 

Protective Colloids. Another approach in preparing and stabilizing metal colloids is by adsorption of macromolecules on their surfaces. A wide variety of materials have been used including gummy gelatinous liquids,(J 0) albumin,(27) Icelandic moss,(28) latex,(22) polyvinylpyrrolidone, (29) antibodies, ( 30 ) carbowax 20M, ( 31 ) polyvinylpyridine, (31 ) and various polymer-water/oil-water mixtures.( 2) These studies clearly indicate that "steric stabilization of metal colloids is also important (along with electronic stabilization).(33)... 

Besides the previously mentioned collagen, a wide variety of natural polymers have been involved in the synthesis of bio-nanohybrid materials with potential application in bone repair and dental prostheses. For instance, some recent examples refer to bionanocomposites based on the combination of HAP with alginate [96,97], chitosan [98,99], bovine serum albumin (BSA) [100], sodium caseinate [101], hyaluronic acid [102], silk fibroin [103,104], silk sericin [105], or polylactic add (PLA) [106,107]. These examples illustrate the increasing interest in the subject of HAP-based biohybrid materials, which has led to almost 400 articles appeared in scientific journals in 2006 alone. 

Flora, K.K. and Brennan, J.D. (2001) Effect of matrix aging on the behavior ofhuman serum albumin entrapped in a tetraethyl orthosilicate-derived glass. Chemistry of Materials, 13, 4170—4179. 

J. D. (2005) Properties ofhuman serum albumin entrapped in sol-gel-derived silica bearing covalently tethered sugars. Chemistry of Materials, 17, 1174-1182. 

Synthesis of gold, silver and their alloy nanoparticles using bovine serum albumin as foaming and stabilizing agent. Journal of Materials Chemistry, 15, 5115-5121. 

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