If you want to work 100% of you biceps and biceps only, isolation exercises are the best. Added compound lifts are not bad, but I believe are not the best way. Any time you add a compound lift in attempts to target a specific muscle group you are technically doing the exact opposite. The more muscle groups that are involved in any anatomical movement requires more ATP and glycogen to be spread out to the muscles required = less for the primary muscle.
Isolated biceps brachii movements will devote nearly all of you energy towards that particular movement. Whenever you do movements like rows, etc., yes you are using you biceps, but also you rhomboids, lattisimus dorsi, posterior delts, errectus spinae, legs for balance, etc (you get what I'm saying). Compound exercises are great for shocking the muscle, neurological pathway training for specific movements, and variety. I don't want what I'm saying to get confused with forearm workouts or anything else, I'm talking specifically about isolating the biceps.
My advice would be if you're looking to increase strength in you biceps. Look at the anatomical movements and make sure you are isolating both heads as much as possible when lifting. Hands always supinated (palms upward) and elbow movement as none existant as possible. To isolate more of the short head, use the elbow flexion machine, but put the seat low enough for shoulder flexion to occure. I have to get back to work, but look up passive and active insufficiencys of any muscle group and you'll get a better idea of what I'm saying as well as ways to increase intensity, actin and myosin interaction, and isolate specific muscles as much as possible. Any more questions feel free to ask
