Carriers, gelatinous

Spray Drying. Spray-dry encapsulation processes (Fig. 7) consist of spraying an intimate mixture of core and shell material into a heated chamber where rapid desolvation occurs to thereby produce microcapsules (24,25). The first step in such processes is to form a concentrated solution of the carrier or shell material in the solvent from which spray drying is to be done. Any water- or solvent-soluble film-forming shell material can, in principle, be used. Water-soluble polymers such as gum arable, modified starch, and hydrolyzed gelatin are used most often. Solutions of these shell materials at 50 wt % soHds have sufficiently low viscosities that they stiU can be atomized without difficulty. It is not unusual to blend gum arable and modified starch with maltodextrins, sucrose, or sorbitol. 

In a second example, a cell—gelatin mixture is cross-linked with glutaraldehyde (43). When soluble enzyme is used for binding, the enzyme is first released from the cell, then recovered and concentrated. Examples of this type of immobilization include binding enzyme to a DEAE-ceUulose—titanium dioxide—polystyrene carrier (44) or absorbing enzyme onto alumina followed by cross-linking with glutaraldehyde (45,46). 

Rasor and Tischer (1998) have brought out the advantages of enzyme immobilization. Examples of penicillin-G to 6-APA, hydrolysis of cephalospwrin C into 7-ACA, hydrolysis of isosorbide diacetate and hydrolysis of 5-(4-hydroxy phenyl) hydantom are cited. De Vroom (1998) has reported covalent attachment of penicillin acylase (EC 3.51.11) from E.Coli in a gelatine-based carrier to give a water insoluble catalyst assemblase which can be recycled many times, and is suitable for the production of semi-synthetic antibiotics in an aqueous environment. The enzyme can be applied both in a hydrolytic fashion and a synthetic fashion. 6-APA was produced from penicillin-G similarly, 7-ADCA was produced from desa acetoxycephalosporin G, a ring expansion product of penicillin G. 

T Yoshioka, M Hashida, S Muranishi, H Sezaki. Specific delivery of mitomycin C to the liver, spleen, and lung Nano-and microspherical carriers of gelatin. Int J Pharm 8 131-141, 1981. 

H. Sezaki, M. Hashida, and S. Muranishi, Gelatin microspheres as carriers for antineoplastic agents, in Optimization of Drug Delivery (H. Bundgaard, A. B. Hansen, and H. Kofod, eds.), Munksgaard, Copenhagen, 1982, p. 316. 

Polymer solids also work as a carrier of photochemical reaction components. The irradiation of a cellulose paper after adsorbing EDTA, Ru(bpy)3 and MV2+ induced rapid formation of MV4 in the solid phase (Table 2) 45,48). The quenching experiments showed that a photoinduced electron relay of EDTA Ru(bpy)2 - —> MV2+occurs in the solid phase just like in the solution. In this reaction the main path for the MV4 formation is through Ru(bpy)2, and the rate of direct reduction of MV2 by cellulose molecule is very small. Such an electron relay occurred also in a gelatine film 47). 

Carriers frequently are stable isotopes of the radionuclide of interest, but they need not be. Nonisotopic carriers are used in a variety of situations. Scavengers are nonisotopic carriers used in precipitations that carry/incorporate other radionuclides into their precipitates indiscriminately. For example, the precipitation of Fe (OH)3 frequently carries, quantitatively, many other cations that are absorbed on the surface of the gelatinous precipitate. Such scavengers are frequently used in chemical separations by precipitation in which a radionuclide is put in a soluble oxidation state, a scavenging precipitation is used to remove radioactive impurities, and then the nuclide is oxidized/reduced to an oxidation state where it can be precipitated. In such scavenging precipitations, holdback carriers are introduced to dilute the radionuclide atoms by inactive atoms and thus prevent them from being scavenged. 

Thixotropic gels (TPGS) of mono- and diglycerides have been used as carriers forsolid dispersions. In the development of a hard gelatin capsule formulation of a poorly water-soluble drug, propantheline bromide, the drug substance was Lrst dissolved in Miglyol 829 and the solution was then converted... 

To assess the purity and quality of the Ab intended for use on preactivated arrays, screen the Ab on NP20 arrays (normal phase arrays) also refer to the product data sheet for the presence of carrier proteins such as BSA and gelatin. 

Balthasar, S., K. Michaelis, et al. (2005). Preparation and characterisation of antibody modified gelatin nanoparticles as drug carrier system for uptake in lymphocytes. Biomaterials 26(15) 2723-32. 

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