Figure 4From: Effect of filtration on morphine and particle content of injections prepared from slow-release oral morphine tabletsParticles less than 5 μm in injection mixtures. Numbers of particles (in thousands) estimated to be in the total injection volumes. The unfiltered extracts were passed successively through a cigarette filter then a syringe filter (0.45 μm or 0.22 μm). Values are mean ± SD (N = 3).Back to article page