Effect of Formulation

The relative effectiveness of nucleating agents in a polymer can be determined by measuring recrystallization exotherms of samples molded at different temperatures (105). The effect of catalyst concentration and filler content has been determined on unsaturated polyesters by using dynamic thermal techniques (124). Effects of formulation change on the heat of mbber vulcanization can be determined by dsc pressurized cells may be needed to reduce volatilization during the cure process (125). 

Measuring the barrier properties of polymers is important for several reasons. The effects of formulation or process changes need to be known, new polymers need to be evaluated, data are needed for a new apphcation before a large investment has been made, and fabricated products need to have performance verified. For some apphcations a full range of data is necessary, including P, Z9, and S plus the effects of temperature and humidity. 

All piroxicam batches were manufactured in compliance with Good Manufacturing Practices, and three formulations having fast, moderate, and slow dissolution were chosen for comparison to a lot of the innovator s product in a human bioavailability study [100]. The resulting pharmacokinetic data provided still another opportunity to examine the effects of formulation variables. To explore the relationship between the in vitro dissolution of piroxicam from these capsules and in vivo absorption, Polli [ 102] used the following previously described [145] deconvolution-based model ... 

Fig. 25 Response surfaces for the effect of formulation variables on percent of piroxicam dissolving from capsules in 10 minutes. (From Ref. 100.)...

In addition to the effects of formulation factors on freeze-drying behavior, it is important for the pharmaceutical scientist to understand basic principles of heat and mass transfer in freeze-drying [29,30]. Because of the high heat input required for sublimation (670 cal/g), transfer of heat from the heated shelf to the sublimation front is often the rate-limiting step in the coupled heat... 

Biopharmaceutical issues to be addressed will include a discussion of the pharmaceutical development process as it relates to in vivo and in vitro performance and the general approach taken concerning bioavailability, bioequivalence, and in vitro dissolution profiles. There should be a comparative analysis of relevant studies—objectives, study design, conduct, outcome, and data analyses. The effects of formulation changes (including different strengths of product and... 

B. Lueckel, B. Helk, D. Bodmer, and H. Leuenberger, Effect of formulation and process variables on the aggregation of freeze dried interleukin-6 (IL-6) after lyophilization and storage, Pharm. Dev. Technol., 3, 337 (1998). 

M. L. Roy, M. J. Pikal, E. C. Rickard, and A. Maloney, The effects of formulation and moisture on the stability of a freeze-dried monoclonal antibody-vinca conjugate A test of the WLF glass transition theory Dev. Biol. Standards, 74, 323 (1991). 

ML Roy, MJ Pikal, EC Rickard, A Maloney. The effects of formulation and moisture... 

J.A. Tamada and K. Comyns, Effect of formulation factors on electroosmotic glucose transport through human skin in vivo. J. Pharmaceutical Sci. 94, 1839-1849 (2005). 

Sawardeker JS, McShefferty J. Effect of formulation of anages-tone acetate on progestational proliferation of rabbit uterus after oral administration. J Pharm Sci 1971 60 1591-1592. 

Mendes RW, Masih SZ, Kanumuri RR. Effect of formulation and process variables on bioequivalency of nitrofurantoin II in vivo—in vitro correlation. J Pharm Sci 1978 67 1616—1619. 

Martmez-Pla JJ, Martin-Biosca Y, Sagrado S, Villanueva-Camanas RM, Medina-Hernindez MJ (2004) Evaluation of the pH effect of formulations on the skin... 

Fig. 15.3 The effect of formulation on foam density at similar gel content...

The effects of formulations containing similar gel content on swell ratio are shown in Fig. 15.6. The results show that at ary specific gel content, the swell ratio reduces with increasing TAC concentration. This confirms the earlier hypothesis that higher TAC concentrations in the crosslinking system produce higher crosshnk density. The results are also in accordance with melt properties where the higher the TAC concentration, the higher the melt modulus. 

Table 15.1 Effect of formulation on foam properties at similar swell ratios...

The influence of adding polyfunctional monomers having different structures and functionality into a dicumyl peroxide-based crosslinking system for LDPE was investigated. Monomers employed were diallyl phthalate, trimethylolpropane trimethacrylate and triallyl cyanurate. The effects of formulation on matrix gel content and on foam density at similar gel content were examined and the dependence of foam density on melt modulus assessed. The applicability of swell ratio for estimating foam density was evaluated and the suitability of triallyl cyanurate as a crosslinking promoter for LDPE foam demonstrated. 20 refs. 

COMPRESSION MOULDED ETHYLENE HOMO- AND COPOLYMER FOAMS. I. EFFECT OF FORMULATION... 

TOBRAMYCIN SULPHATE FROM POLYMETHYLMETHACRYLATE IMPLANTS 177 Table 2—Effect of formulation factors on computer-generated fast (a) and slow ) phase rate constants... 

Rangarajan M, Zatz JL. Effect of formulation on the topical delivery of alpha-tocopherol. 

Mount eld, R. J., S. Senepin, M. Schleimer, I. V folter, and B. Bittner (2000). Potential inhibitory effects of formulation ingredients on intestinal cytochrome P46fi.J. Pharm., 211 89-92. 

Ten Tije, A. J, J. Verweij, W. J. Loos, and A. Sparreboom (2003). Pharmacological effects of formulation vehicles-Hnplications for cancer chemotherapyn. Pharmacokinet, 42 665-685. 

Nazzal, S., Nutan, M., Palamakula, A., Shah, R., Zaghloul, A.A., and Khan, M.A. (2002) Optimization of a self-nanoemulsi ed tablet dosage form of Ubiquinone using response surface methodology effect of formulation ingredientslnt. J. Pharm., 240 103-114. 

Patil, P, J. Joshi, and P. Paradkar. 2004. Effect of formulation variables on preparation and evaluation of gelled self-emulsifying drug delivery systems (SEDDS) of ketoprotetfPS Pharm Sci Te[Pg.527]

Formulation profile, which consists of physical and chemical characteristics required for the products, drug-excipient compatibility studies, and the effect of formulation on in vitro dissolution... 

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