Functionalized Magnetic Emulsion for Genomic Applications

Abstract

Narrowly size-distributed functionalized magnetic emulsions with diameters between 200 and 300 nm bearing reactive amine or carboxylic groups were prepared respectively via single adsorption or layer-by-layer adsorption process. The colloidal stability of the functionalized magnetic emulsion was related to the polymer adsorbed amount and to the adsorption methodology. The single adsorption of poly(ethyleneimine) onto negatively charged magnetic emulsion led to amino-containing magnetic nanodroplets for nucleic acid extraction, concentration and amplification. The enzymatic amplification of adsorbed nucleic acid molecules (i.e. RNA) was found to be related to both initial nucleic acid concentration and the used magnetic particles in the amplification step. The undesirable inhibition phenomena observed in the enzymatic amplification (i.e. RT-PCR) process was eliminated by the addition of appropriate negatively charged polyelectrolyte before the amplification step. The encapsulation of magnetic emulsion via layer-by-layer polyelectrolytes adsorption process was used to elaborate functionalized core-shell magnetic colloids. The characterized final magnetic dispersions were evaluated in specific nucleic acids capture and detection, and in proteins immobilization process.

Magnetic Nanoparticles PCR Enzyme‐Linked Gene Assay for Quantitative Detection of BCR/ABL Fusion Gene in Chronic Myelogenous Leukemia

“…This finding is consistent with other systems using MNPs in the reaction that improve the specificity of the technique and separate the unwanted substances from the target molecules . In addition, a given amount of the cationic MNPs can be used for performing nucleic acid extraction via electrostatic interaction as well as amplification that enhanced sensitivity and specificity of the detection .…”

Dual-stimuli responsive PNiPAM microgel achieved via layer-by-layer assembly: Magnetic and thermoresponsive

“…The LbL is a very simple, versatile and elegant technique which involves the sequential adsorption of polycations and polyanions on any charged surface, irrespective of shape and size. Polyelectrolyte multilayers (PEM) as well as NP have been successfully deposited on thermoresponsive microgels [15,[28][29][30][31][32][33]. The rational behind this core-shell structure is that the thickness (number of layers) and porosity (nature of polyelectrolyte pair and of the assembly conditions) of polyelectrolyte shells assembled around the (loaded) microgel provide barrier properties for regulating molecules trafficking for controlled release, while MNP incorporated within that shell will provide the inductive heat (with the help of an external magnetic field) to cause the collapse of the microgel and acts as a trigger mechanism to release the drug.…”

Detection of Vibrio cholerae Using the Intrinsic Catalytic Activity of a Magnetic Polymeric Nanoparticle

“…This was possibly due to the steric effect of MPNP surface which impeded the primer and target sequence recognition although the spacer, −C 6 –, was incorporated into the 5′-end of the forward primer. , The adsorbed NH 2 – ctxAB -F onto the particle surface in flat configuration (if presented) might be also attributed to the poor availability of the primer for hybridization . However, unlike cationic MPNP, the inhibition of the amplification process by interaction of primer or DNA polymerase onto the carboxylated MPNP surface can be avoided. − …”