Small-volume injectable emulsions

Small-Volume Parenterals Color, clarity of solutions, particulate matter, pH, sterility, endotoxins. Powders for injection solutions include clarity, color, reconstitution time and water content, pH, sterility, endotoxins/pyrogens, and particulate matter. Suspensions for injection should include additional particle size distribution, redispersability, and rheological properties. Emulsion for injection should include phase separation, viscosity, mean size, and distribution of dispersed globules. 

Permeability reductions were also observed by McAuliffe (9), and his results are shown in Figure 14. He used a Boise sandstone core with an initial permeability of 1600 mD and injected a 0.5% OAV emulsion having average oil-droplet sizes of 1 and 12 xm. The small-diameter emulsion reduced the permeability from 1600 to 900 mD after 10 pore volumes of the injected emulsion the 12-fxm emulsion was much more effective in reducing the core permeability. After 10 pore volumes had been injected, the permeability was reduced to 30 mD, almost a 50-fold reduction. 

The widest range of parenteral products are however, the small volume parenterals (SVPs). These may be sterile solutions for injecting directly into the patient. They may be concentrated solutions or suspensions or emulsions or even solids (solid dosage forms may be anhydrous, crystalline, or freeze dried [lyophilized]) for dilution or reconstitution in LVPs for direct injection or infusion into the patient. 

Class 10,000 areas are suitable to prepare solutions that shall be sterile but cannot be sterilized in their final containers (referring to that sterile filtration is needed before filling) to prepare solutions of large volume parenterals that can be sterilized in their final containers to prepare, filter, fill and seal solutions of small volume parenterals fc50ml) and eye drops to prepare, filter, fill and seal oral solutions that can not be sterilized by steam sterilization to prepare, fill and seal ointments, creams, suspensions, emulsions that can not be sterilized in their final containers and to purify, dry, and package bulk pharmaceuticals for preparing injections. 

Studies [109,110] have shown that small changes in physical properties of emulsions can influence the elimination rate of these formulations from the blood. Indeed, an organ distribution study of stearylamine-based cationic or deoxycholic acid-based anionic nanosized emulsions and Intralipid, a well-known commercial anionic emulsion, containing 14C-CO was carried out following injection into the tail vein of male BALB/c mice (20-26g) at a volume of 5mL/kg [111, 112], Since CO... 

Figure 16 shows the results when 20 pore volumes of an emulsion having a 3.1- xm mean droplet size is injected into an 1170-mD sand pack and is followed by several pore volumes of water (ii). After emulsion injection, a permeability reduction of about 50% is observed. With water injection, the effluent concentration drops to 0 after one pore volume, whereas the permeability is unaltered. For this dilute emulsion, the droplets are captured in the porous medium, and this capture leads to blocking of the flow paths. Figure 16 shows that once the droplets are captured, they do not re-enter the flow stream, velocity being constant. Soo and Radke (ii) proposed the following physical interpretation for the results of Figure 15. Initially oil droplets are preferentially captured in the small-size pores, and as injection proceeds, more and more of the small pores become blocked. This blockage leads to a flow diversion toward larger size pores, and the rate...

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