Development of a lateral flow dipstick for simultaneous and semi‐quantitative analysis of dihydroartemisinin and piperaquine in an artemisinin combination therapy

Abstract

Dihydroartemisinin (DHA) and piperaquine (PPQ) are two drugs used in an artemisinin‐based combination therapy (ACT). The circulation of counterfeit antimalarial drugs demands the development of simple, point‐of‐care (POC) tests for monitoring drug quality. Here we aimed to design an antibody‐based lateral flow dipstick assay for simultaneous quality control of DHA and PPQ. To obtain a monoclonal antibody (mAb) for PPQ, one structural unit of the symmetric PPQ molecule was used to derive a carboxylic acid for linkage to a carrier protein as immunogen. Screening of hybridoma cells identified an mAb 4D112B2 that reacted with the PPQ‐based immunogen. A highly‐sensitive icELISA was designed based on this mAb, which showed 50% inhibition concentration of PPQ at 1.66 ng/mL and a working range of 0.35 – 7.40 ng/mL. The mAb showed 10.2, 15.9 and 30.4% cross reactivity to hydroxychloroquine sulfate, chloroquine and amodiaquine, respectively. No cross reactivity was observed to lumefantrine, mefloquine artemisinin and its derivatives. Using our previous DHA dipstick design, a lateral flow dipstick for simultaneous analysis of PPQ and DHA was developed. The indicator ranges for PPQ and DHA were 2 – 5 μg/mL and 250 – 500 ng/mL, respectively. The dipstick was used to semi‐quantitatively analyze PPQ and DHA content in commercial ACT drugs, which produced agreeable results to those determined by high‐performance liquid chromatography. This combination dipstick makes it a potential POC device for quality control of the two active ingredients in a commonly used ACT.

Structure-switching aptamer sensors for the specific detection of piperaquine and mefloquine

“…Although, in its current format, the assay requires access to a fluorimeter, in the future, the sensor could be adapted to a colorimetric readout negating the need for lab-based equipment and a drug standard curve. The assay could be modeled after a dipstick immunoassay format and the aptamers would provide superior compound specificity over current drugbinding antibodies (44). An aptamer-based dipstick format would further improve access to antimalarial drug use and quality testing worldwide.…”

Malaria Research for Tailored Control and Elimination Strategies in the Greater Mekong Subregion

“… 63 To enable the point-of-care quality control of antimalarial drugs under remote endemic settings, we developed lateral flow dipsticks, similar to the malaria RDTs, for rapid assessment of ACT qualities. 64 – 67 In light of the historical circulation of fake artesunate drugs in Myanmar, 68 we performed a follow-up assessment of ACT drugs in private sectors of Myanmar. 69 Our survey revealed an astonishingly high proportion of ART monotherapies (>35%) and identified an artesunate injection sample as a falsified drug containing no active ingredient.…”