TY - JOUR
T1 - Reduction of the magnetic signal from unbound magnetic markers for magnetic immunoassay without bound/free separation
AU - Tsukamoto, A.
AU - Kuma, H.
AU - Saitoh, K.
AU - Kandori, A.
AU - Yoshinaga, K.
AU - Sugiura, Y.
AU - Hamasaki, N.
AU - Enpuku, K.
N1 - Funding Information:
This work was partly supported by the Ministry of Economy, Trade and Industry for the regional renaissance consortium R&D program.
PY - 2007/10/1
Y1 - 2007/10/1
N2 - We investigated the effect of adding magnetic shielding and applying of a compensation field to reduce the magnetic signal from unbound free markers. When the initial immunoassay system was used without the additional shielding box, the signal intensity of the liquid markers normalized by the weight of the Fe3O4 was 1/2700 of the dried markers. By installing the additional shielding box, the reduction factor was improved to 1/10,000. We successfully reduced the magnetic signal of the liquid marker further by applying a compensation field. The magnetic signal of the free marker obtained by applying a compensation field of -18 nT was 1.4 mΦ0, which was close to the system noise level. Field compensation at the very local area just around the SQUID is sufficient for reducing of the magnetic signal from the free marker.
AB - We investigated the effect of adding magnetic shielding and applying of a compensation field to reduce the magnetic signal from unbound free markers. When the initial immunoassay system was used without the additional shielding box, the signal intensity of the liquid markers normalized by the weight of the Fe3O4 was 1/2700 of the dried markers. By installing the additional shielding box, the reduction factor was improved to 1/10,000. We successfully reduced the magnetic signal of the liquid marker further by applying a compensation field. The magnetic signal of the free marker obtained by applying a compensation field of -18 nT was 1.4 mΦ0, which was close to the system noise level. Field compensation at the very local area just around the SQUID is sufficient for reducing of the magnetic signal from the free marker.
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U2 - 10.1016/j.physc.2007.04.284
DO - 10.1016/j.physc.2007.04.284
M3 - Article
AN - SCOPUS:34548495354
VL - 463-465
SP - 1024
EP - 1028
JO - Physica C: Superconductivity and its Applications
JF - Physica C: Superconductivity and its Applications
SN - 0921-4534
IS - SUPPL.
ER -