Carbopol effect

Determination of Na " and Na" ions in raw cosmetic materials was conducted with the developed method of flame photometry. A necessity of development of method of samples preparation arose up in the work process, as this spicily-aromatic raw material contained pectin in amount 0.1-0.5% and that prevented preparation of samples by standard method of extracts dilution and required incineration of analyzed sample, time of analysis was increased in 60 times. It was established that CaCl, solution with the concentration 0,4 % caused destmctions of the carbopol gel. It was established that the addition of 0,1% CaCl, and 0,1% NaCl salts solutions into the system intensified the effect of negative action of these salts onto the gel stmcture and the gel destmcted completely. 

Li, S., et al. 2003. Effect of HPMC and Carbopol on the release and floating properties of gastric floating drug delivery systems using factorial design. Int J Pharm 253 13. 

From a formulative point of view, it is important to take into consideration that the base in which liposomes are incorporated could also affect the drug delivery profile as well as the interactions between the liposomes and skin structures. The effect of formulation bases on dyphylline skin permeation from liposomes was examined by Touitou et al. [9]. In this work the effect of four bases for dyphylline liposomes (polyethylene glycol (PEG), carbopol gel, a PEG-enhancer base, and water) was studied. With these bases, the lowest skin permeation flux and a superior skin partitioning of liposomal dyphylline were reported for the PEG base, suggesting that this base favored dyphylline accumulation within the skin. A number of liposomes are currently marketed by cosmetic raw material companies for incorporation in different bases to obtain final products. It is important to keep in mind that the delivery properties of the final formulation could be altered by the vehicle used and should be tested to confirm any performance characteristics claimed. 

Takeuchi, H., Matsui, Y., Yamamoto, H., and Kawashima, Y. Mucoadhesive properties of carbopol or chitosan-coated liposomes and their effectiveness in the oral administration of calcitonin to rats. J. Contr. Rel. 86 235—242, 2003. 

Takeuchi H, Yamamoto H, Kawashima Y (2001) Mucoadhesive nanoparticulate systems for peptide drug delivery. Adv Drug Del Rev 47( 1 ) 39—54 Takeuchi H, Matsui Y, Yamamoto H, Kawashima Y (2003) Mucoadhesive properties of carbopol or chitosan-coated liposomes and their effectiveness in the oral administration of calcitonin to rats. J Control Rel 86(2-3) 235-242 Takeuchi H, Matsui Y, Sugihara H, Yamamoto H, Kawashima Y (2005a) Effectiveness of submicron-sized, chitosan-coated liposomes in oral administration of peptide drugs. Int J Pharm 303(1-2) 160-170... 

Crystalline cellulose, hydroxypropyl cellulose, and Carbopol 934 have been studied in combination with lyophilized insulin as bioadhesive powder dosage forms for nasal delivery. Each formulation tested resulted in an decrease in plasma glucose level after nasal administration in dog and rabbit models. The most effective formulation, crystalline cellulose blended with insulin, decreased the plasma glucose level to 49% of the control value. In ternary systems the lyophilized Carbopol 934 and insulin blend with crystalline cellulose powder has been the most effective, leading to a hypoglycemia on the order of one-third of the effect obtained after intravenous injection of the same dose of insulin. The plasma glucose levels obtained in the volunteers after administration of the insulin-Carbopol-crystalline cellulose powder formulation were quite variable [38],... 

Carbopol 394P Chitosan HPMC PVA In vitro Initial release at a constant rate Chitosan microspheres exhibited size-dependent release effect 41... 

Ugwoke, M. I., Agu, R. U., Jorissen, M., Augustijns, P., Sciot, R., Verbeke, N., and Kinget, R. (2000), Nasal toxicological investigations of Carbopol 971P formulation of apomor-phine Effects on ciliary beat frequency of human nasal primary cell culture and in vivo on rabbit nasal mucosa, Eur. J. Pharm. Sci., 9, 387-396. 

Combining thermal- with pH-dependent gelation, Kumar et al. [86] developed a combination of methylcellulose 15% and carbopol 0.3%. This composition exhibited a sol-to-gel transition between 25 and 37 °C with a pH increase from 4 to 7.4 [203], A possible mechanism for the thermal effect could be the decrease in the degree of the methylcellulose hydration, while the polyacrylic acid can transform into a gel upon an increase in pH due to the buffering properties of the tear fluid [1]. 

To increase the residence time in the nasal mucosa, a bioadhesive formulation may be one of the most reasonable approaches. In fact, microspheres containing bioadhesive polymers such as starch, albumin, and Sephadex with a particle size of 40-60 pm have been found to be cleared from the nasal cavity much more slowly than solutions. Starch microspheres improved the nasal absorption of insulin, with synergistic effects of some absorption enhancers in sheep. In another paper, dry powder containing starch and Carbopol 974P showed significantly higher bioavailability after nasal administration than the formulation without Carbopol. ° Chitosan, already mentioned above, also has a bioadhesive property and is found to be useful as a potent absorption enhancer for nasal peptide delivery. Other bioadhesive polymer systems,... 

Meshali MM, El-Sayed GM, El-Helw A. Effect of added substances on theophylline release from carbopol 934P matrix. STP Pharma Sci 1997 7(3) 195-198. 

Disperse the Methocel in 40 mL of hot (80-90°C), water. CMl overnight in a refrigerator to effect solution. Disperse the Carbopol 934 in 20 mL of water. Adjust the pH of the dispersion to 7.0 by adding sufficient 1% sodium hydroxide solution (about 12 mL is required per 100 mL) and bring the volume to 40 mL with purified water. Dissolve the methylparaben in the propylene glycol. Mix the Methocel, Carbopol 934, and propylene glycol fractions using caution to avoid the incorporation of air. 

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