	US 12,435,359 B2
	Fractional initiator hybridization chain reaction
Niles A Pierce, Pasadena, CA (US); and Harry M. T. Choi, Pasadena, CA (US)
Assigned to California Institute of Technology, Pasadena, CA (US)
Filed by California Institute of Technology, Pasadena, CA (US)
Filed on Dec. 3, 2021, as Appl. No. 17/457,572.
Application 16/569,510 is a division of application No. 15/639,100, filed on Jun. 30, 2017, granted, now 10,450,599, issued on Oct. 22, 2019.
Application 17/457,572 is a continuation of application No. 16/569,510, filed on Sep. 12, 2019, granted, now 11,214,825.
Claims priority of provisional application 62/358,462, filed on Jul. 5, 2016.
Prior Publication US 2022/0090163 A1, Mar. 24, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. C12Q 1/682 (2018.01); C12Q 1/6816 (2018.01)

CPC C12Q 1/682 (2013.01) [C12Q 1/6816 (2013.01)]

37 Claims

1. A composition, comprising:

a target molecule,

a first fractional initiator probe comprising:

a first target binding region and a first fractional initiator,

a second fractional initiator probe comprising:

a second target binding region and a second fractional initiator,

and a first hairpin monomer comprising:

a first input domain comprising a first toehold and a first stem section, and a first output domain comprising a first loop and a complement to the first stem section;

wherein the first and second target binding regions are capable of binding the target molecule so as to colocalize the first and second fractional initiators, and

wherein the colocalized first and second fractional initiators are capable of binding to the first input domain of the first hairpin monomer to open the first hairpin monomer and expose the first output domain.