Adhesive radiolabeled

Nakamura et al. ° studied the adhesion of water-soluble and neutral polymers, hydroxypropyl cellulose (HPC), xanthan gum (XG), tamarind gum (TG), and polyvinyl alcohol (PVA) to nasal mucosa in vitro and in vivo. The polymers, mixed with a dye, were applied as powders to the nasal cavity of rabbits, and the remaining dye residue was determined at 2, 4, and 6 h after nasal instillation with a thin fiberscope. The polymer XG showed the longest residence time of the dye in the cavity, followed by TG, HPC, and PVA in decreasing order. For the mixture XG and XG-PVA (2 8), some residue of dye could still be observed 6h after administration. The order of adhesion of these polymers to agar plates in vitro agreed with that of their mucoadhesion in vivo. Ilium et al. introduced bioadhesive microspheres for nasal delivery of poorly absorbable drugs. Radiolabelled microspheres made from diethylaminoethyl (DEAE)-dextran, starch microspheres, and albumin microspheres were administered to human volunteers and appeared to be cleared significantly slower than solutions or... 

Static Adsorption of Plasma Proteins on Glass. Initial studies of the interaction of proteins with artificial surfaces concerned the highly simplified situation of static adsorption on glass from solutions of purified radiolabeled human plasma proteins. Albumin was chosen as a major plasma protein known for its non thrombogenic properties (5>6). Fibrinogen and fibronectin, on the contrary, are major proteins of plasma which enhance platelet and cellular adhesion (4.5.7.23-25). 

A.3 Indirect Evaluation of In Vivo Absorption Using Radiolabeled Tissue Adhesive... 

Platelets PF-4, p-TG, thromboxane B2 Platelet activation markers Platelet microparticles Gamma imaging of radiolabeled platelets, ln-labeled platelet survival Platelet function analysis Platelet count/adhesion Platelet aggregation... 

ATR-FTIR spectroscopy was used to monitor the uptake of urea into a silicone polymer. Analysis of the time-dependent changes in the IR absorbances of urea and silicone leads to an estimate of the diffusion coefficient for urea that is in close agreement with a value obtained using a bulk transport method (involving radiolabelled permeant). The silicone polymer was medical grade silicone pressure-sensitive adhesive (X7 201). ATR-FTIR is proposed as a rapid and accurate method of rapidly and accurately determining solute diffusion within a polymer matrix. 12 refs. 

The leach rate of silicone oil additives from the silicone topcoat was readily determined using radiolabeled oils in both fresh and marine water systems (9). Use of radiolabeled oils simplifies the study of their environmental partitioning, since each component of the matrix can be easily analyzed and quantified using radiometric detection. The approach was to synthesize radiolabeled polydiphenyl-dimethylsiloxane oil which is similar in composition to that used in determination of barnacle adhesion measurements (see Figure 2). Next, the oil was added to RTVll, catalyzed and applied to metal coupons which were subsequently suspended in fresh and salt water fish tanks. Coupons, soil and sediment were analyzed monthly for one year for mass balance determination. 

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