Table 2.

Process variables for microspheres with HPMC (100 cps).

Formulation variables	Particle size	% Entrapment efficiency	% Buoyancy
Polymer ratio
1:1	221.2 ± 3.2	61.2 ± 0.2	68.4 ± 2.1
1:2	232.8 ± 4.8	64.5 ± 0.8	76.5 ± 3.6
1:3	236.0 ± 6.1	65.5 ± 3.2	79.1 ± 2.2
Drug:polymer ratio
1:1	220.1 ± 1.3	61.8 ± 3.2	67.2 ± 8.1
1:2	229.1 ± 4.5	65.3 ± 1.2	78.8 ± 5.1
1:3	233.5 ± 1.8	68.6 ± 2.6	79.0 ± 6.3
Emulsifier concentration (% w/v)
0.46	251.5 ± 0.5	70.5 ± 3.1	80.2 ± 1.1
0.66	243.6 ± 4.2	66.2 ± 3.2	77.9 ± 2.1
0.86	229.4 ± 3.6	62.3 ± 6.9	75.3 ± 7.3
Stirring speed
600	248.2 ± 3.2	69.1 ± 4.2	81.2 ± 3.5
900	236.7 ± 3.6	62.4 ± 5.0	77.2 ± 2.3