Table 1.

Process variables for microspheres with HPMC (5 cps).

Formulation variables	Particle size	% Entrapment efficiency	% Buoyancy
Polymer ratio
1:1	181.1 ± 1.5	58.5 ± 4.6	70.3 ± 1.1
1:2	192.5 ± 2.4	62.5 ± 3.2	77.2 ± 2.3
1:3	204.2 ± 3.5	63.2 ± 1.3	80.3 ± 3.3
Drug:polymer ratio
1:1	179.6 ± 3.5	60.7 ± 2.3	70.4 ± 2.6
1:2	189.4 ± 4.5	64.8 ± 6.3	78.1 ± 5.8
1:3	193.2 ± 7.2	66.6 ± 4.9	81.3 ± 6.4
Emulsifier concentration (% w/v)
0.46	208.1 ± 4.2	67.2 ± 5.3	84.3 ± 8.0
0.66	194.2 ± 1.1	64.3 ± 7.2	80.2 ± 6.1
0.86	182.3 ± 3.2	58.6 ± 6.2	79.4 ± 0.1
Stirring speed
600	211.1 ± 0.3	65.2 ± 1.2	82.4 ± 4.2
900	201.2 ± 2.4	59.5 ± 2.6	78.1 ± 2.1