title: Detection of lysozyme magnetic relaxation switches based on aptamer-functionalized superparamagnetic nanoparticles.
abstract: Magnetic relaxation switch (MRSw) detection is based on aggregate formation or dissociation when magnetic nanoparticles (MNPs) bind to target molecules. In the aggregated state, the dephasing rate of nearby proton spins is higher than in the dispersed state, resulting in a decrease in the spin-spin relaxation time, T(2). In this work, an MRSw-based nanosensor for lysozyme (Lys) protein detection was achieved using iron oxide nanoparticles conjugated with either Lys aptamer or linker DNA, which can hybridize with the extended part of the aptamer to form clusters. Upon the addition of Lys, the aptamers bind with their targets, leading to disassembly of clusters and an increase in T(2). A detection limit in the nanomolar range was achieved for Lys detection in both buffer and human serum. The determination of Lys level in different types of cancer cell lysates was also performed to demonstrate detection in real clinical samples.
authors: Center for Research at the Bio/nano Interface, Department of Chemistry, Shands Cancer Center, University of Florida, Gainesville, Florida 32611-7200, USA.
authors: Suwussa
authors: S
authors: Bamrungsap
authors: Mohammed Ibrahim
authors: MI
authors: Shukoor
authors: Tao
authors: T
authors: Chen
authors: Kwame
authors: K
authors: Sefah
authors: Weihong
authors: W
authors: Tan
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry*; D015374:Biosensing Techniques; D045744:Cell Line, Tumor; D006801:Humans; D008280:Magnetics; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D009113:Muramidase / Q000032:analysis* / Q000097:blood; D013113:Spin Labels
chemical_list: D052157:Aptamers, Nucleotide; D058185:Magnetite Nanoparticles; D013113:Spin Labels; D009113:Muramidase