       

2011A1830         BL14B2DNA ᅛᐃࢁ⣬࡬ࡢࣞ࢔࢔࣮ࢫࡢ྾╔࣓࢝ࢽࢬ࣒ࡢゎ᫂㸸ࣞ࢔࢔࣮ࢫࡢศ㞳ᅇ཰࡬ࡢᛂ⏝࡟ྥࡅ࡚A Study on the Mechanism of Adsorption of Rare Earth Elements 㻔REE㻕 toDNA Fixed to Filter paper to Establish Recovery andSeparation Method of REEs㧗ᶫ ჆ኵ a, ᐑᆅ ளἋ⨾ a, ⏣୰ ୓ஓ b, ᶓᒣ ⏤ె a
Yoshio Takahashia, Asami Miyajia, Kazuya Tanakab, and Yuka Yokoyamaaa

ᗈᓥ኱Ꮫ኱Ꮫ㝔⌮Ꮫ◊✲⛉ᆅ⌫ᝨᫍࢩࢫࢸ࣒Ꮫᑓᨷ,ᗈᓥ኱Ꮫࢧࢫࢸࢼࣈࣝࢹ࢕࣋ࣟࢵࣉ࣓ࣥࢺ◊✲ࢭࣥࢱ࣮ aDepartment of Earth and Planetary Systems Science, Graduate School of Science, Hiroshima University,bSustainable Development Research Center, , Hiroshima Universityb ࣞ࢔࢔࣮ࢫ㸦REE㸧ࢆศ㞳࣭ᅇ཰ࡍࡿࡓࡵࡢ᪉ἲ࡜ࡋ࡚ࠊᢸయ࡜ࡋ࡚ DNA ࢆᅛᐃࡋࡓࢁ⣬ࢆ⏝࠸ࡓᡭἲࢆㄪ࡭ࡓࠋࡇࡢᡭἲࡢ࣓࢝ࢽࢬ࣒ࢆゎ᫂ࡋࠊᡭἲࡢ᭱㐺໬ࢆ⾜࠺ࡓࡵ࡟ࠊDNA ᅛᐃࢁ⣬࡟྾╔ࡉࢀࡓ REE ࢆ X ⥺྾཰ᚤ⣽ᵓ㐀ἲ㸦EXAFS ἲ㸧࡟ࡼࡾ᫂ࡽ࠿࡟ࡋࡓࠋREE ࣃࢱ࣮ࣥ࠿ࡽࠊ
ࡇࢀࡽᢸయࡀ REE ࡢศ㞳ᅇ཰࡟᭷ຠ࡛࠶ࡾࠊREE ࡢ⤖ྜࢧ࢖ࢺ࡜ࡋ࡚ࣜࣥ㓟ᇶࡀ㔜せ࡛࠶ࡿࡇ࡜ࡀ EXAFS ἲ࠿ࡽ᫂ࡽ࠿࡟࡞ࡗࡓࠋࡉࡽ࡟ࡦࡶ≧ DNA ࡬ࡢ REE ࡢ྾╔࡟ࡘ࠸࡚ࡶㄪ࡭ࡓࠋ࣮࣮࢟࣡ࢻ㸸 ࣞ࢔࢔࣮ࢫࠊࣂࢡࢸࣜ࢔ࠊDNAࠊࢧࢣⓑᏊࠊ྾╔ࠊEXAFS⫼ᬒ࡜◊✲┠ⓗ㸸ᕼᅵ㢮ඖ⣲㸦ࣞ࢔࢔࣮ࢫ㸹REE㸧ࡣࠊࣛࣥࢱࣀ࢖ࢻ࡜ࢫ࢝ࣥࢪ࣒࢘ࠊ࢖ࢵࢺ࣒ࣜ࢘ࡢ⥲⛠࡛࠶ࡾࠊྛ REE ඖ⣲ࡣಶࠎࡢ≉ᛶ࡟ᛂࡌ࡚ࠊᡃࠎࡢ㌟ࡢᅇࡾࡢᵝࠎ࡞〇ရ࡟ᖜᗈࡃ౑ࢃࢀ࡚࠸ࡿࠋ⌧ᅾ REE ㈨※ࡢ౪⤥ࡣࠊ೫ᅾᛶࡀ㧗ࡃࠊ㖔▼᥇ྲྀ࣭⢭㖔࣭〇㘐࡟࠾ࡅࡿࢥࢫࢺࡢᏳࡉ࠿ࡽࠊ୰ᅜࡀ࡯ࡰ⊂༨ࡋ࡚࠸ࡿࠋࡇ࠺ࡋࡓ⊂༨≧ែࢆඞ᭹ࡍࡿୖ࡛ࠊᏳ౯࡛ຠ⋡ⓗ࡞ REE ࡢᅇ཰࣭ศ㞳ᢏ⾡ࡢ㛤Ⓨࡣ㔜せ࡛࠶ࡿࠋ୍᪉ࠊREE ࡣኳ↛࡛ࡢᣲືࡀ┦஫࡟ࡼࡃఝ࡚࠾ࡾࠊ㖔▼࠿ࡽࡶΰྜ≀࡜ࡋ࡚ᚓࡽࢀࡿࡓࡵࠊྛඖ⣲ࡀࡑࢀࡒࢀࡢ⏝㏵࡟ᛂࡌ࡚฼⏝ࡉࢀࡿ࡟ࡣࠊREE ࡢ┦஫ศ㞳ࡀ㔜せ࡟࡞ࡿࠋࡇࢀࡲ࡛ REE ࡢ┦஫ศ㞳ࡣࠊࣜࣥ㓟࢚ࢫࢸࣝ⣔ࡢᢳฟ๣ࢆ⏝࠸ࡓ⁐፹ᢳฟἲ࡟౫Ꮡࡋ࡚࠸ࡿࡀࠊࡇࡢ᪉ἲࡣ≉ู࡞ฎ⌮ࢆせࡍࡿ᭷ᶵ⁐፹ࢆከ㔞࡟ᚲせ࡜ࡍࡿࡓࡵࠊ⎔ቃ࡟㈇Ⲵࡀ࠿࠿ࡿࠋᡃࠎࡣ᪤࡟ࣂࢡࢸࣜ࢔ࡸⓑᏊ࡟ࡼࡿ REE ࡢศ㞳⃰⦰ࡀྍ⬟࡛࠶ࡿࡇ࡜ࢆぢฟࡋ[1-4]ࠊࡑࡢ࣓࢝ࢽࢬ࣒ࢆᨺᑕගࢆ⏝࠸ࡓᗈᇦ X ⥺྾཰ᚤ⣽ᵓ㐀㻔EXAFS㻕ἲ࡛ㄪ࡭ࠊࣂࢡࢸࣜ࢔࡬ࡢ REE ࡢ⃰⦰ࡣࠊ⣽⬊ቨ࡟ྵࡲࢀࡿࣜࣥ㓟࡜ࡢ⤖ྜ࡟ࡼࡿࡇ࡜ࢆ᫂ࡽ࠿࡟ࡋࡓ㻔ㄢ㢟㸸2011A1702㻕ࠋࡋ࠿ࡋࠊࣂࢡࢸࣜ࢔ࡣ౑⏝๓࡟ᇵ㣴ࡀᚲせ࡛࠶ࡾࠊࡲࡓẚ㍑ⓗศゎࡋࡸࡍࡃᇵ㣴ࡋࡓྠࡌࣂࢡࢸࣜ࢔ࡢ⧞㏉ࡋࡢ฼⏝ࡣᅔ㞴࡛࠶ࡿࠋࡑࡇ࡛ᡃࠎࡣࠊᏳ౯࡛⎔ቃ㈇Ⲵࡀᑠࡉ࡞ REE ࡢᅇ཰࣭ศ㞳ἲ࡜ࡋ࡚ࠊྠࡌࣜࣥ㓟ᇶࢆ᭷ࡍࡿ⏕య㧗ศᏊ࡛࠶ࡿ DNA ࢆ⏝࠸ࡓᡭἲࡢ◊✲࡟╔ᡭࡋࡓࠋDNA ࡣᏳ౯࠿ࡘ኱㔞࡟౪⤥࡛ࡁࡿ㈨ᮦ࡛
࠶ࡾࠊDNA ࡟ࡼࡿ REE ࡢศ㞳ᅇ཰ࡀྍ⬟࡟࡞ࢀࡤࠊ௒ᚋࡢ REE ࡢ㈨※㛤Ⓨࡸࣜࢧ࢖ࢡࣝ࡟࠾࠸࡚᭷⏝࡞ᢏ⾡࡟࡞ࡾᚓࡿࠋ࡜ࡇࢁࡀࠊDNA ࢆ REE ศ㞳⏝࣒࢝ࣛ࡟⏝࠸ࡓሙྜࠊDNA ࡢ␯Ỉᛶࡀᙉ࠸ࡓࡵ࡟ REE ࢆྵࡴ⁐ᾮࡀ࣒࢝ࣛࢆᐃᖖⓗ࡟ὶࢀ࡞࠸ࡇ࡜ࡀุ᫂ࡋࡓࠋࡑࡇ࡛ᡃࠎࡣࠊDNAࢆᯫᶫศᏊ㸦࣮ࣜࣥ࢝㸧࡛ࢁ⣬㸦ࢭ࣮ࣝࣟࢫ㸧࡟ᅛᐃࡋࠊࢁ⣬ࡢぶỈᛶࢆ฼⏝ࡍࡿࡇ࡜࡛ࠊỈࡢᐃᖖⓗ࡞ὶฟࢆྍ⬟࡟ࡋࡓࠋࡑࡇ࡛ᮏ◊✲࡛ࡣࠊDNA ᅛᐃࢁ⣬࡟ࡼࡿ REE ࡢศ㞳ᅇ཰ἲࡢ᭷⏝ᛶࢆ᫂ࡽ࠿࡟ࡍࡿࡓࡵ࡟ࠊDNA ᅛᐃࢁ⣬࡬ࡢ REE ࡢ྾╔ᶵᵓࢆ EXAFS ἲ࡛᫂ࡽ࠿࡟ࡋࠊREE ࡢ྾╔ᵓ㐀࡜྾╔≉ᛶ࡜ࡢ㛵ಀࢆゎ᫂ࡍࡿࠋࡲࡓẚ㍑࡜ࡋ࡚ࠊࡦࡶ≧ࡢ DNA ࡸࢧࢣⓑᏊ࡟ᑐࡍࡿ
REE ࡢ྾╔࡟ࡘ࠸࡚ࡶㄪ࡭ࡓࠋ

ᐇ㦂㸸DNA ᅛᐃࢁ⣬ࠊࡦࡶ≧ DNA ࠾ࡼࡧࢧࢣⓑᏊ࡟ᑐࡍࡿ REE ࡢ྾╔ࡣࠊࡇࢀࡲ࡛ሗ࿌ࡋࡓࣂࢡࢸ
ࣜ࢔࡟㢮ఝࡢ྾╔ᣲືࢆ♧ࡋࠊ㔜 REE ࢆ⃰⦰ࡍࡿࡇ࡜ࡀศ࠿ࡗࡓ[4]ࠋࡇ࠺ࡋࡓ⃰⦰࣭┦஫ศ㞳ࡢ࣓࢝ࢽࢬ࣒ࢆゎ᫂ࡍࡿࡓࡵ࡟ࠊEXAFS ἲ࡛ᚓࡽࢀࡓ REE ࡢ⤖ྜࢧ࢖ࢺࢆ᥎ᐃࡋࡓࠋ௒ᅇࡣ୺࡟
DNA ᅛᐃࢁ⣬ࠊࡦࡶ≧ DNAࠊࢧࢣⓑᏊ࡟྾╔ࡉࢀࡓ LaࠊDyࠊLu ࡟ࡘ࠸࡚ࠊBL14B2 ࡛ EXAFS
ࡢ ᐃࢆ⾜ࡗࡓࠋLa ࡟ࡘ࠸࡚ࡣࠊL3 ྾཰➃࡛ࡣከ㟁Ꮚບ㉳ࡢᙳ㡪ࡀ኱ࡁ࠸ࡓࡵࠊK ྾཰➃࡛ࡢᐃࢆ⾜ࡗࡓࠋDy ࡜ Lu ࡟ࡘ࠸࡚ࡣࠊL3 ྾཰➃࡛ᐇ㦂ࢆ⾜ࡗࡓࠋẚ㍑࡜ࡋ࡚ࠊLn resin㸦REE ࡜ࡣከᗙࡢࣜࣥ㓟ᇶࢆ௓ࡋ࡚㘒యࢆ⏕ᡂ㸧ࠊcellulose phosphate㸦CP; REE ࡜ࡣᑡᩘࡢࣜࣥ㓟ᇶࢆ௓ࡋ࡚㘒⏕ᡂ㸧ࠊcarboxymethyl cellulose㸦CMC; REE ࡜ࡣ࢝ࣝ࣎࢟ࢩࣝᇶࢆ௓ࡋ࡚㘒⏕ᡂ㸧࡟྾╔ࡉࢀࡓ
REE ࡢ EXAFS ࢫ࣌ࢡࢺࣝࡶ ᐃࡋࡓࠋ⤖ᯝ࠾ࡼࡧ⪃ᐹ㸸⤖ᯝࡢ౛࡜ࡋ࡚ᅗ㸯࡟ pH4 ࡛ DNA ⤖ྜࢁ⣬ࠊCPࠊCMCࠊLn resin ࡟྾╔ࡉࢀࡓ Lu ࡢ k ✵㛫
ࡢ EXAFS ࢫ࣌ࢡࢺࣝ࠾ࡼࡧືᚄᵓ㐀㛵ᩘ㻔RSF㻕ࢆ♧ࡋࡓࠋࡑࡢ⤖ᯝࠊDNA ⤖ྜࢁ⣬࡟྾╔ࡉࢀࡓLu ࡛ࡣࠊR+ǼR =3.3 Å ௜㏆࡟ࣆ࣮ࢡࡀぢࡽࢀࡓࠋFEFF ࡛ᚓࡓࣃ࣓࣮ࣛࢱࢆ⏝࠸ࡓࣇ࢕ࢵࢸ࢕ࣥࢢ࡟ࡼࡾࠊࡇࡢᩓ஘ࡣ➨㸰㏆᥋ཎᏊ࡜ࡋ࡚ࣜࣥཎᏊࢆ௬ᐃࡍࡿࡇ࡜࡛ㄝ࡛᫂ࡁࡓࠋࡇࡢ᫬ࠊᚓࡽ
ࢀࡓ Lu-P ࡢཎᏊ㛫㊥㞳ࡣ 3.86 Å ࡛࠶ࡗࡓࠋྠᵝ࡟᭱㏆᥋ࡢ㓟⣲࡜ࡢ Lu-O ࡢ㊥㞳ࡣ 2.26 Å ࡛࠶ࡗࡓࠋࣜࣥࡢࣆ࣮ࢡࡀ᫂☜࡟ぢࡽࢀࡓࡇ࡜ࡣࠊࣂࢡࢸࣜ࢔ࡸࢧࢣⓑᏊ࡟྾╔ࡉࢀࡓ Lu ࡜ྠᵝ࡛࠶ࡾࠊDNA ⤖ྜࢁ⣬࡟࠾ࡅࡿ㔜 REE ࡢ⃰㞟࡟㛵㐃ࡍࡿ࡜ࡳࡽࢀࡿࠋࡓࡔࡋࠊࣜࣥ㓟ࡶྵࡵࡓ㓄఩Ꮚ࡜ࡢᖹᆒⓗ࡞⤖ྜ㊥㞳ࢆ཯ᫎࡍࡿ ࡜ ࡳ ࡽࢀࡿLu-O ࡣࠊࣂࢡࢸࣜ࢔ࡸ Ln resin ࡢሙྜ㸦Lu-O: ⣙ 2.20Å㸧࡟ẚ࡭࡚ࡸࡸ㛗ࡃ࡞ࡗࡓࠋࡲࡓࣜࣥ࡜ࡢ㊥㞳ࡶࣂࢡ ࢸ ࣜ ࢔ ࡸ Lnresin ࡢሙྜ㸦Lu-P:⣙ 3.80 Å㸧ࡼࡾࡶ㛗ࡃ࡞ࡗࡓࠋࡇࢀࡽࡣࠊLu ࡟ᑐࡍࡿࣜࣥ㓟௨እࡢ⤖ྜࢧ࢖ࢺࡀࣂࢡࢸࣜ
࢔ࡸ Ln resin ࡢሙྜࡼࡾࡶከ࠸ࡇ࡜
ࢆ♧၀ࡋ࡚࠾ࡾࠊ
ࣂࢡࢸࣜ࢔ࡸ Lnresin ࡟ ẚ ࡭ ࡚ 㔜REE ࡢ ⃰ 㞟 ࡀ ༑ศ࡛࡞࠸ࡇ࡜࡜ᩚ
ྜⓗ࡛࠶ࡿࠋᅗ㸰࡟ࡣࠊpH4 ࡛ DNA ⤖ྜࢁ⣬ࠊࢧࢣⓑᏊࠊࡦࡶ≧ DNAࠊLn resin ࡟྾╔ࡉࢀࡓ Dy ࡢ EXAFS
ࢫ࣌ࢡࢺࣝ࡜ RSF ࢆ♧ࡋࡓࠋDNA ⤖ྜࢁ⣬࠾ࡼࡧࢧࢣⓑᏊ࡟྾╔ࡉࢀࡓ Dy ࡛ࡣࠊLu ࡜ྠᵝ࡟
R+ǼR =3.3 Å ௜㏆࡟ࣆ࣮ࢡࡀぢࡽࢀࡓࡀࠊLu ࡢሙྜ࡯࡝ᙉ࠸ᩓ஘࡛ࡣ࡞࠿ࡗࡓࠋࡇࢀࡶ Dy ࡟ẚ࡭࡚ Lu ࡀࡇࢀࡽࡢ≀㉁࡟ࡼࡾ⃰⦰ࡍࡿࡇ࡜࡜㛵㐃ࡀ࠶ࡿ࡜ࡳࡽࢀࡿࠋࡓࡔࡋࠊࡦࡶ≧ DNA ࡟྾╔ࡉࢀࡓ Dy ࡛ࡣࠊࣜࣥ࡟ࡼࡿᩓ஘ࡀ DNA ⤖ྜࢁ⣬࠾ࡼࡧࢧࢣⓑᏊ࡟྾╔ࡉࢀࡓ Dy ࡼࡾࡣᙉ࠿ࡗࡓࠋࡇࢀࡣࠊࡦࡶ≧ DNA ࡛ REE ࡢぶ࿴ᛶࡀ඲యⓗ࡟኱ࡁ࠸ࡇ࡜࡜ᩚྜⓗ࡛࠶ࡿࠋ௒ᚋࡢㄢ㢟㸸ᮏ◊✲࡛⏝࠸ࡓ࣒࢝ࣛἲ࡟ᢸᣢࡋࡓ DNA ᅛᐃࢁ⣬ࡣࠊREE ࡢ྾╔ᐜ㔞ࡀ 1 meq/g ⛬ᗘ࡛࠶ࡗࡓࠋࡇࡢᐜ㔞࡛ࡣࠊᐇ⏝࡟⏝࠸ࡿሙྜ࡟ࡣ྾╔ᐜ㔞ࡀ༑ศ࡛࡞࠸ྍ⬟ᛶࡀ࠶ࡿࠋࡦࡶ≧ DNA ࡣࠊREEࡢ྾╔ᐜ㔞ࡀࡼࡾ኱ࡁ࠸ྍ⬟ᛶࡀ࠶ࡿ㸦ᮍ ᐃ㸧ࠋࡇࢀࢆά࠿ࡍࡓࡵ࡟ࠊࡦࡶ≧ DNA ࡟ REE ࢆ྾╔ࡉࡏࢤࣝ໬ࡉࡏࡓᚋ࡛ࠊࡇࡢࢤࣝࢆ࣒࢝ࣛ࡟඘ሸࡋࠊࡑࡢᚋ࡛ REE ࡟㓟ࢆῧຍࡋ࡛ศ㞳ࡍࡿ᪉ἲࢆ௒ᚋ᳨ウࡋࡓ࠸ࠋཧ⪃ᩥ⊩㸸[1] Y. Takahashi, T. Hirata, T. Ozaki, H. Shimizu, and D. Fortin, Chem. Geol. 244, 569 㻔2007㻕.
[2] Y. Takahashi, M. Yamamoto, Y. Yamamoto, and K. Tanaka, Geochim. Cosmochim. Acta 74, 5443
㻔2010㻕.
[3] 㧗ᶫ჆ኵࠊὸᒸ⪽ࠊ㏆⸨࿴༤ࠊᮍ᮶ᮦᩱ 9, 65 㻔2011㻕.
[4] 㧗ᶫ჆ኵࠊ㏆⸨࿴༤ࠊBio Industry 14, 42 㻔2011㻕.