Bulk formulations

In the first example, procaine penicillin, an aqueous vehicle containing the soluble components (such as lecithin, sodium citrate, povidone, and polyoxyethylene sorbitan monooleate) is filtered through a 0.22 pm membrane filter, heat sterilized, and transferred into a presterilized mixing-filling tank. The sterile antibiotic powder, which has previously been produced by freeze-drying, sterile crystallization, or spray-drying, is aseptically added to the sterile solution while mixing. After all tests have been completed on the bulk formulation, it is aseptically filled. 

John et al. [37] described a colorimetric method for the estimation of primaquine phosphate. Sample solutions of different dilutions (0.15-0.6 mL) of the drug (6-24 pg/mL) were treated with 5 mL of 1% cerric ammonium sulfate in dilute nitric acid and made up to 25 mL with water. The absorbance of the resulting light purple solution was measured at 480 nm after similar 30 min. Beer s law was obeyed from 5 30 pg/mL of primaquine phosphate. The method is applicable to bulk formulations in addition to tablets and capsule formulation. 

In developing a method that requires filtration, adsorption of the analyte onto the filter must be taken into account. For dilute solutions of adriamycin, >95% is adsorbed to cellulose ester membranes and about 40% to polytetrafluoroethylene membranes [19]. For more concentrated solutions, as would be encountered in bulk formulation testing, filter ad-... 

Microscope Particle Count Test. Particulate tests were conducted on LYOGUARD trays. Based on actual use fill volumes, testing was conducted using a rinse volume of 1.8 L of water. Since LYOGUARD trays are intended for lyophilization of bulk formulations, the results are subject to the Large-volume Injections Guidelines (Table 6). 

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