“…Techniques have been developed to improve the sensitivities of LFAs, including kinetics and transport control ( Yang et al, 2013 ; Rivas et al, 2014 ; Tang et al, 2017 ; Ishii et al, 2018 ), biochemical signal amplification ( Hu et al, 2013 ; Parolo et al, 2013 ; Panferov et al, 2016 ), improved labeling ( Choi et al, 2010 ), and sample enrichment. Sample enrichment techniques include centrifugal filtration ( Corstjens et al, 2015 ), immunomagnetic separation ( Panferov et al, 2017 ; Ben Aissa et al, 2021 ), electrophoretic and phasic separation ( Wu et al, 2014 ; Chiu et al, 2015 ; Kim et al, 2017 ), isotachophoresis ( Moghadam et al, 2015 ), dialysis ( Tang et al, 2016 ), and test-zone pre-enrichment ( Zhang et al, 2020 ). These systems are not suitable for low-resource, point-of-care settings as they require expensive reagents, equipment, and/or complex procedures.…”