Yield and molar activity of [¹¹C]CH₂O-DNPH^a.

Entry	Solventb	N-Oxide	T c (°C)	Yield (%)		A m d (GBq μmol−1)	n g
				EOBe	EOTf	EOTf
1	DMSO	TMAO	120	55 ± 7.0	37 ± 4.3	90 ± 36	3
2	DMSO	NMO	120	57 ± 9.3	38 ± 6.2	190 ± 29	5
3	DMSO	OMT	120	55 ± 9.5	37 ± 6.2	158 ± 41	6
4	DPSO	OMT	150	57 ± 1.5	39 ± 0.8	335 ± 52	4
5	DMF	TMAO	120	36	23	123	1

^aValues are presented as mean ± sd. [¹¹C]CH₂O eluted from the reaction column was introduced into a cartridge containing 2,4-dinitrophenylhydrazine (DNPH) to yield [¹¹C]CH₂O-2,4-dinitrophenylhydrazone ([¹¹C]CH₂O-DNPH).

^bThe designated solvents (DMSO and DMF, 250 μL; DPSO, 250 mg) were mixed with MeCN (750 μL) and N-oxide (TMAO and NMO, 10 mg; OMT, 25 mg) and used to prepare the reaction column.

^cTemperature of reaction column.

^dMolar activity.

^eAt the end of bombardment.

^fAt the end of [¹¹C]CH₂O transfer.

^gNumber of experiments.