Antibiotics | Practical Molecular Biology

Working concentrations and stock solutions.

	Stock solution		Working concentration:
	Stock solution		Strict control		Weak control
	mg/ml:		µg/ml	dilution	µg/ml	dilution
Ampicillin	50 (H₂O*)	-20^oC	20	0.4 µl/ml	60-125	1.2-2.5 µl/ml
Carbenicillin	50 (H₂O, 50%EtOH)	-20^oC	20	0.4 µl/ml	60-200	1.2-4 µl/ml
Chloramphenicol	34 (EtOH, MetOH)	-20^oC	25	0.7 µl/ml	170	5 µl/ml
D-cycloserine*	10 (0.1M NaP pH8.0)	+4^oC	200	20 µl/ml
Gentamycin	10 (H₂O)	-20^oC	15	1.5 µl/ml
Hygromycin B	10 (H₂O)	-20^oC	10	1 µl/ml	400	40 µl/ml
Kanamicin	50 (H₂O)	+4^oC- -20^oC	10	0.2 µl/ml	50	1 µl/ml
Kasugamycin	10 (H₂O)	-20^oC	1000	100 µl/ml
Nalidixic acid	5 (H₂O, pH to 11 /NaOH)	-20^oC	15	3.0 µl/ml
Neomycin	10 (H₂O)	-20^oC	100	10 µl/ml	800	80 µl/ml
Rifampicin**	34 (MetOH)	-20^oC	150	4.4 µl/ml
Spectinomycin	10 (H₂O)	-20^oC	100	10 µl/ml
Streptomicin	50 (H₂O)	-20^oC	10	0.2 µl/ml	50	1 µl/ml
Tetracycline***	5 - 12.5 (EtOH, 70%EtOH)	-20^oC	10	2 µl/ml	50 100	10 µl/ml 20 µl/ml

* - Unstable solution, prepare just before use;
** - Light sensitive;
*** - Light sensitive, Mg²⁺ - inhibitor;