Paper‐Origami‐Based Multiplexed Malaria Diagnostics from Whole Blood

Abstract

We demonstrate, for the first time, the multiplexed determination of microbial species from whole blood using the paper‐folding technique of origami to enable the sequential steps of DNA extraction, loop‐mediated isothermal amplification (LAMP), and array‐based fluorescence detection. A low‐cost handheld flashlight reveals the presence of the final DNA amplicon to the naked eye, providing a “sample‐to‐answer” diagnosis from a finger‐prick volume of human blood, within 45 min, with minimal user intervention. To demonstrate the method, we showed the identification of three species of Plasmodium, analyzing 80 patient samples benchmarked against the gold‐standard polymerase chain reaction (PCR) assay in an operator‐blinded study. We also show that the test retains its diagnostic accuracy when using stored or fixed reference samples.

Valve‐Enabled Sample Preparation and RNA Amplification in a Coffee Mug for Zika Virus Detection

“…Examples of these products are FTAcard, [16][17][18][19][20][21][22] chitosancoated paper, [23,24] glass-fiber paper, [25][26][27][28] and polyethersulfone filter paper. Examples of these products are FTAcard, [16][17][18][19][20][21][22] chitosancoated paper, [23,24] glass-fiber paper, [25][26][27][28] and polyethersulfone filter paper.…”

Carbon Nanodot–Based Fluorescent Method for Virus DNA Analysis with Isothermal Strand Displacement Amplification

“…Isothermal strand displacement amplification is employed utilizing Bst DNA polymerase, which can simultaneously achieve double‐stranded DNA (dsDNA) displacement and primer extension at a constant temperature . The isothermal amplification strategy avoids the need of thermal cyclers and can be easily integrated with other technologies, which is suitable for point‐of‐care testing applications . On the other hand, we have introduced carbon nanodots (CDs), a new class of carbon nanomaterials, as the fluorescent sources in this biosensor .…”

Sample-to-answer palm-sized nucleic acid testing device towards low-cost malaria mass screening

“…However, PCR-based assays are poorly suited to perform in field settings as they require specialized equipment for sample preparation and skilled personnel (Britton et al, 2016b). Alternative NATs, such as loop-mediated isothermal amplification (LAMP) assays (Abdul-Ghani, 2014; Goyal et al, 2015; Han, 2013; Hsiang et al, 2014; Morris et al, 2015; Oriero et al, 2015; Patel et al, 2014; Sattabongkot et al, 2014; Singh et al, 2013; Sirichaisinthop et al, 2011; Surabattula et al, 2013), recombinase polymerase amplification (RPA) assays (Cordray and Richards-Kortum, 2015; Kersting et al, 2014), as well as helicase dependent amplification (HAD) assays (Li et al, 2013) have shown high analytical sensitivity and great potential for field deployment by integrating with microfluidic (Liu et al, 2016) and paper based devices (Xu et al, 2016). Among isothermal methods, LAMP is the most studied assay for malaria detection and holds great promise for commercialization.…”