Anti-sense oligonucleotide labeled with technetium-99m using hydrazinonictinamide derivative and N-hydroxysuccinimidyl S-acetylmercaptoacetyltriglycline: A comparison of radiochemical behaviors and biological properties

Table 1 Labeling efficacy and radiochemical purity of labeled compounds (mean ± SD)

	Interval between binding and labeling (d)			Radioactivity of 99mTcO4- (MBq)
	15	30	60	370	740	1480
Labeling efficiency (%)
Via HYNIC	57.36 ± 3.69	62.13 ± 4.25	62.87 ± 3.04	58.74 ± 5.32	62.86 ± 4.27	63.28 ± 3.38
Via NHS-MAG3	67.35 ± 4.03	68.35 ± 3.56	69.85 ± 4.63	68.67 ± 4.82	70.31 ± 5.09	71.56 ± 5.37
Radiochemical purity (%)
99mTc-HYNIC-ASON	95.75 ± 5.21	96.32 ± 4.92	95.86 ± 5.28	96.56 ± 4.45	96.87 ± 3.65	97.16 ± 4.34
99mTc-MAG3-ASON	96.43 ± 4.69	95.67 ± 5.17	96.39 ± 4.78	96.35 ± 6.12	95.86 ± 4.67	96.54 ± 5.65

ASON: Anti-sense oligonucleotide; HYNIC: Hydrazino nicotinamide derivative; NHS-MAG₃: N-hydroxysuccinimidyl S-acetylmercaptoacetyltriglycline.

Table 2 Radiochemical stability of labeled compounds (%, mean ± SD)

	Incubation time at room temperature (h)			Incubation time at 37°C (h)
	1	2	4	1	2	4
99mTc-HYNIC-ASON	93.43 ± 5.32	89.17 ± 4.62	87.16 ± 5.36	92.75 ± 4.46	89.52 ± 3.67	86.86 ± 5.49
99mTc-MAG3-ASON	97.26 ± 6.02	96.68 ± 5.54	96.39 ± 4.68	95.86 ± 5.69	95.47 ± 4.07	94.79 ± 5.34

Table 3 Biodistribution of labeled compounds in BALB/c mice (% ID/g) (mean ± SD)

Tissue	0.5 h		1 h		2 h		4 h		Paired	t-test
	M	H	M	H	M	H	M	H
Blood	1.12 ± 0.76	6.21 ± 1.03	2.38 ± 0.63	6.56 ± 1.11	1.14 ± 0.42	3.58 ± 1.21	1.10 ± 0.09	2.83 ± 0.54	t = 4.347	P = 0.022
Heart	0.62 ± 0.31	2.13 ± 0.45	0.58 ± 0.07	1.64 ± 0.34	0.32 ± 0.05	1.16 ± 0.12	0.18 ± 0.08	0.81 ± 0.13	t = 5.362	P = 0.013
Lungs	3.11 ± 0.82	2.68 ± 0.65	3.87 ± 1.36	3.23 ± 1.04	3.04 ± 0.79	2.78 ± 1.03	2.08 ± 0.62	1.76 ± 0.36	t = -4.934	P = 0.016
Liver	7.52 ± 2.45	11.46 ± 2.31	13.19 ± 1.47	15.24 ± 2.53	9.21 ± 1.03	12.89 ± 1.68	9.48 ± 2.56	10.46 ± 1.97	t = 3.806	P = 0.032
Kidneys	11.42 ± 3.34	4.17 ± 1.05	17.13 ± 2.86	5.03 ± 0.94	24.58 ± 3.57	2.78 ± 0.68	21.95 ± 4.02	2.28 ± 0.95	t = -4.511	P = 0.020
Spleen	2.71 ± 1.62	4.87 ± 2.36	5.65 ± 0.93	6.08 ± 1.93	5.35 ± 0.26	4.08 ± 1.54	4.84 ± 1.33	5.21 ± 2.04	t = 0.603	P = 0.589
Stomach	1.08 ± 0.86	7.46 ± 2.13	2.58 ± 0.95	11.48 ± 3.01	1.73 ± 0.21	7.49 ± 1.86	1.41 ± 0.34	7.85 ± 3.02	t = 9.901	P = 0.002
Intestines	0.53 ± 0.31	1.26 ± 0.31	0.86 ± 0.14	2.68 ± 0.95	1.23 ± 0.19	6.44 ± 2.13	1.96 ± 0.53	7.84 ± 2.34	t = 2.706	P = 0.073
Muscle	1.35 ± 0.16	0.54 ± 0.21	0.87 ± 0.63	0.94 ± 0.81	0.75 ± 0.08	0.42 ± 0.06	0.64 ± 0.15	0.19 ± 0.05	t = -2.095	P = 0.127

M: ^99mTc-MAG₃-ASON; H: ^99mTc-HYNIC-ASON. Statistical analysis of the same tissue distribution of radioactivity was made after the injection of ^99mTc-HYNIC-ASON and ^99mTc-MAG₃-ASON.

Table 4 Human colon carcinoma HT29 cellular uptake of ^99mTc-HYNIC-ASON and ^99mTc-MAG₃-ASON (mean ± SD)

	10 min	20 min	40 min	60 min	120 min
99mTc-HYNIC-ASON (%)	0.43 ± 0.08	0.56 ± 0.21	0.93 ± 0.54	1.42 ± 0.64	1.67 ± 0.86
99mTc-MAG3-ASON (%)	2.78 ± 0.81	5.64 ± 0.51	7.82 ± 2.53	13.63 ± 2.71	15.25 ± 3.13