In-vitro binding assay study of ^99mTc-flouroquinolones with E. coli, Salmonella and Ps. aeruginosa

Peer review under responsibility of Alexandria University Faculty of Medicine.

Available online 28 October 2014

Figures & data

Figure 3 Complex formation of ^99mTc-enorfloxacin.

Figure 1 Essential structure of all quinolone antibiotics: the blue drawn remainder of R is usually piperazine; if the connection contains fluorine (red), it is a fluoroquinolone.

Figure 2 Complex formation of ^99mTc-ciprofloxacin.

Figure 4 Complex formation of ^99mTc-ofloxacin.

Table 1 Labelling efficiency of ^99mTc with fluoroquinolones.

Sr. no	Antibiotic	Labelling efficiencies (%)	Colloid	Free TcO4^−1
1	Ciprofloxacin	>96	2.27 ± 0.12	0.80 ± 0.03
2	Enorfloxacin	>95	3.45 ± 0.10	1.50 ± 0.02
3	Ofloxacin	>97	2.05 ± 0.09	0.95 ± 0.02

Table 2 Activity of free ^99mTc⁻¹ and labelled fluoroquinolones on live and killed bacteria after different time intervals.

Labelled compound	Live or killed stains	Bacterial species	Activity (%) after 30 min	Activity (%) after 1.0 h	Activity (%) after 4.0 h	Average activity (%)
Free ^99mTc^−1	Live stains	E. coli	0.11	0.02	0.05	0.06
		Salmonella	0.11	0.12	0.04	0.09
		Ps. aeruginosa	0.02	0.01	0.04	0.02
	Killed stains	E. coli	0.00	0.19	0.07	0.09
		Salmonella	0.00	0.12	0.06	0.06
		Ps. aeruginosa	0.05	0.12	0.11	0.09
^99mTc-ciprofloxacin	Live stains	E. coli	37	27	34	32.67
		Salmonella	22	34	29	28.33
		Ps. aeruginosa	46	42	37	41.67
	Killed stains	E. coli	46	39	40	41.67
		Salmonella	43	37	47	42.33
		Ps. aeruginosa	37	39	37	37.67
^99mTc-ofloxacin	Live stains	E. coli	34	41	41	38.67
		Salmonella	46	49	46	47.00
		Ps. aeruginosa	10	31	46	29.00
	Killed stains	E. coli	5	19	13	12.33
		Salmonella	6	10	17	11.00
		Ps. aeruginosa	8	31	46	28.33
^99mTc-enorfloxacin	Live stains	E. coli	45	48	44	45.67
		Salmonella	34	47	38	39.67
		Ps. aeruginosa	21	16	14	17.00
	Killed stains	E. coli	44	36	13	31.00
		Salmonella	49	27	19	31.67
		Ps. aeruginosa	29	35	26	30.00