Nucleic acid amplification-free detection of DNA and RNA at ultralow concentration

2021 ◽  
Vol 71 ◽  
pp. 145-150
Author(s):  
Yan Cao ◽  
Zhenrong Zheng ◽  
Harold G Monbouquette
2020 ◽  
Author(s):  
Nikunja Kolluri ◽  
Nikolas Albarran ◽  
Andy Fan ◽  
Alex Olson ◽  
Manish Sagar ◽  
...  

AbstractNucleic acid amplification tests (NAATs), which amplify and detect pathogen nucleic acids, are vital methods to diagnose diseases, particularly in cases where patients exhibit low levels of infection. For many blood-borne pathogens such as HIV or Plasmodium, it is necessary to first extract pathogen RNA or DNA from patient blood prior to analysis with NAATs. Traditional nucleic acid extraction methods are expensive, resource-intensive and are often difficult to deploy to resource-limited areas where many blood-borne infections are widespread. Here, we describe a portable, paper-and-plastic device for instrument-free nucleic acid extraction from whole blood, which we call SNAPflex, that builds upon our previous work extracting RNA in a 2D platform from nasopharyngeal swabs. We demonstrated improved extraction of HIV RNA from simulated patient samples compared to traditional extraction methods and long-term stability of extracted RNA without the need for cold storage. We further demonstrated successful extraction and recovery of Plasmodium falciparum DNA from simulated patient samples with superior recovery compared to existing extraction methods. The SNAPflex device extracts and purifies DNA and RNA from whole blood which can be amplified with traditional NAATs, and was designed to easily manufacture and integrate into existing health systems.


Author(s):  
B.A. Hamkalo ◽  
S. Narayanswami ◽  
A.P. Kausch

The availability of nonradioactive methods to label nucleic acids an the resultant rapid and greater sensitivity of detection has catapulted the technique of in situ hybridization to become the method of choice to locate of specific DNA and RNA sequences on chromosomes and in whole cells in cytological preparations in many areas of biology. It is being applied to problems of fundamental interest to basic cell and molecular biologists such as the organization of the interphase nucleus in the context of putative functional domains; it is making major contributions to genome mapping efforts; and it is being applied to the analysis of clinical specimens. Although fluorescence detection of nucleic acid hybrids is routinely used, certain questions require greater resolution. For example, very closely linked sequences may not be separable using fluorescence; the precise location of sequences with respect to chromosome structures may be below the resolution of light microscopy(LM); and the relative positions of sequences on very small chromosomes may not be feasible.


Sign in / Sign up

Export Citation Format

Share Document