Application of carboxyphenylboronic acid-functionalized magnetic nanoparticles for extracting nucleic acid from seeds

On-site detection of Sporothrix globosa using immunoglobulin Y, magnetic separation and loop-mediated isothermal amplification

BACKGROUND

Sporothrix globosa (S. globosa) is an agricultural activity-related but neglected pathogenic fungus responsible for sporotrichosis. Timely detection is crucial for managing and preventing its spread. However, due to the lack of efficient recognition elements for enriching S. globosa, the current approaches for detecting S. globosa are not simple and/or sensitive enough. This hinders their wider application of fast screening.

RESULTS

Herein, we successfully prepared immunoglobulin Y (IgY) targeting S. globosa, and developed a rapid and accurate detection method, improving upon current limited and inadequate detection approaches. Our method combined the use of IgY and loop-mediated isothermal amplification (LAMP) to enhance detection sensitivity and specificity simultaneously. The IgY was fabricated on magnetic beads to specifically concentrate S. globosa in samples, while LAMP amplified the captured target after simple boiling DNA extraction. By using our method, as low as 4.66 × 102 Cells mL-1S. globosa was accurately detected in soil and corn straw samples. We further integrated this assay into a portable toolbox for sample-to-result detection in resource-limited areas. By using this toolbox, we have colorimetrically detected soil and corn straw samples contaminated by S. globosa, suggesting the promising on-site detection potential.

SIGNIFICANCE AND NOVELTY

A new IgY recognizing S. globosa was prepared. Through the combination of IgY enrichment and LAMP amplification, the detection sensitivity and specificity were improved simultaneously. This method eliminated thermal cycling, simplified the operation, and reduced the analysis time. Compared to existing methods, our approach is more suitable for on-site detection and can significantly improve public health responses to sporotrichosis outbreaks.

Magnetic particles for integrated nucleic acid purification, amplification and detection without pipetting

Nucleic acid amplification based detection plays an important role in food safety, environmental monitoring and clinical diagnosis. However, traditional nucleic acid detection process involves transferring liquid from one tube to another by pipetting. It requires trained persons, equipped labs and consumes lots of time. The ideal nucleic acid detection is integrated, closed, simplified and automated. Magnetic particles actuated by magnetic fields can efficiently adsorb nucleic acids and promote integrated nucleic acid assays without pipetting driven by pumps and centrifuges. We will comprehensively review magnetic particles assisted integrated system for nucleic acid detection and hope it can inspire further related study.

Magnetic nano fluids for isolation of genomic DNA and total RNA from various prokaryote and eukaryote cells

The correct isolation of nucleic acid from various cells is an important preliminary step before many biochemical and diagnostic processes such as cloning, sequencing, replication, hybridization, and complementary DNA (cDNA) synthesis. In this study, the coated magnetic nanoparticles (MNFs) with Tween 20 and oleic acid because of paramagnetic and bio-compatibility properties used in the extractions of genomic DNA (gDNA) and total RNA from prokaryote and eukaryote cells. The amount and accuracy of gDNA and total RNA extracted were proved via agarose gel electrophoresis, digestion and polymerase chain reaction (PCR) techniques. According to UV-Vis spectrophotometry data and gDNA and ribosomal RNA (rRNA) bands observed on the agarose gel, the results showed that extraction of this nano-kit can be comparable with the existing methods used to purifying nucleic acids such as purification based on the use of Cetyltrimethylammonium bromide (CTAB) and phenol-chloroform methods. Characterization of the particles defines them to be ~34.85 nm in diameter and exhibiting high saturation magnetization (28 emu/g). Elimination of hazardous reagents such as phenol and chloroform from extraction solutions, the replacement for inorganic coating such as silica with organic oil, and reduction of reaction time are some advantages of this method. Therefore, according to the challenges in the nucleic acid purification pathway, the use of these kits can be remarkable.