| CPC B01J 20/22 (2013.01) [B01J 20/103 (2013.01); B01J 20/287 (2013.01); B01J 20/288 (2013.01); C09B 67/0096 (2013.01); G01N 21/643 (2013.01); G01N 33/241 (2013.01); G01N 33/2823 (2013.01)] | 12 Claims |

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1. A method of tracing fluid flow in a subterranean formation, comprising:
mixing a functionalized fluorescent tracer into a fluid to yield a tracer fluid, wherein the functionalized fluorescent tracer comprises a fluorescent dye and a hydrophobic functional group;
flowing the tracer fluid into a first subterranean formation;
recovering a sample from the first subterranean formation or a second subterranean formation; and
extracting the functionalized fluorescent tracer from the sample using a Type I or Type II silica-based sorbent, wherein
the Type I silica-based sorbent comprises a hydrophobic functional group and an ionic functional group, wherein the ionic functional group is positively charged, and
the Type II silica-based sorbent comprises a hydrophobic functional group and an ionic functional group, wherein the ionic functional group is negatively charged.
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