Dual-imaging model of SQUID biosusceptometry for locating tumors targeted using magnetic nanoparticles

Abstract

BackgroundFor intraoperative imaging in operating theaters or preoperative imaging in clinics, compact and economic integration rather than large and expensive equipment is required to coregister structural and functional imaging. However, current technologies, such as those integrating optical and gamma cameras or infrared and fluorescence imaging, involve certain drawbacks, including the radioactive biorisks of nuclear medicine indicators and the inconvenience of conducting measurements in dark environments.MethodsTo specifically and magnetically label liver tumors, an anti-alpha-fetoprotein (AFP) reagent was synthesized from biosafe iron oxide magnetic nanoparticles (MNPs) coated with anti-AFP antibody and solved in a phosphate buffered saline solution. In addition, a novel dual-imaging model system integrating an optical camera and magnetic scanning superconducting-quantum-interference device (SQUID) biosusceptometry (SSB) was proposed. The simultaneous coregistration of low-field magnetic images of MNP distributions and optical images of anatomical regions enabled the tumor distribution to be determined easily and in real time. To simulate targeted MNPs within animals, fewer reagents than the injected dose were contained in a microtube as a sample for the phantom test. The phantom test was conducted to examine the system characteristics and the analysis method of dual images. Furthermore, the animal tests were classified into two types, with liver tumors implanted either on the backs or livers of rats. The tumors on the backs were to visually confirm the imaging results of the phantom test, and the tumors on the livers were to simulate real cases in hepatocellular carcinoma people.ResultsA phantom test was conducted using the proposed analysis method; favorable contour agreement was shown between the MNP distribution in optical and magnetic images. Consequently, the positioning and discrimination of liver tumors implanted on the backs and livers of rats were verified by conducting in vivo and ex vivo tests. The results of tissue staining verified the feasibility of using this method to determine the distribution of liver tumors.ConclusionThe results of this study indicate the clinical potential of using anti-AFP-mediated MNPs and the dual-imaging model SSB for discriminating and locating tumors.

Enhanced cell proliferation and osteogenic differentiation in electrospun PLGA/hydroxyapatite nanofibre scaffolds incorporated with graphene oxide

“…PLGA/GO/HA nanofibrous matrices were prepared by electrospinning the admixture of PLGA and HA blended with GO [ 28 ]. Briefly, 0.2 g HA was dispersed in 1mL HFIP and 1.8 g PLGA was dissolved in 9 mL HFIP.…”

Novel Integration of an Ultrasound Probe and a Rotational-Scanning SQUID Biosusceptometer for Diagnosing Liver Tumors

“…Here, it is desired to explain the positive regions, where tumor existed, in magnetic images covered not only Section A and B, for example, also the opposite side of Section A and B. The reason is that the tumor not only distributed in originally-implanted livers, but also might metastasize to lungs as some previous cases [14]. Here, the former distribution could be easily imaged by the US probe, but the latter must be examined by MRI or invasive surgery and tissue stain instead of the US probe due to air existence in lung.…”

“…The sensitivity of the rotational SSB was approximately 500 pT/ √ Hz, which was less favorable than the 100 fT/ √ Hz of the SQUID intrinsic noise at 400 Hz. The environmental noise mainly originated from the concentric excitation coil, and the low noise suppression capability was attributable to the larger area of the first-order pickup coil compared with that of the used design, of which the diameter was 1 cm [14]. To suppress the effects of background noise, the signals of no samples subjected to the same scanning process were obtained to be removed from those of samples.…”

“…The first-generation SSB enables only magnetic measurement, and the second-generation SSB, which is equipped with an integrated optical video camera, can coregister structural optical images and functional magnetic images [14]. This study proposes a new-generation SSB in which the US probe and SSB probe are integrated.…”

Mussel-Inspired Gold Nanoparticle and PLGA/L-Lysine-g-Graphene Oxide Composite Scaffolds for Bone Defect Repair

“… 11 A common modification is to blend some bioactive nanoparticles with PLGA to prepare composites, such as hydroxyapatite, graphene oxide, carbon nanotubes, and others. 12–14 These nanoparticles can significantly improve scaffolds’ mechanical strength, regulate cell function, and facilitate bone cell growth and fusion of the material with the surrounding bone tissue. This strategy can effectively improve the bone repair capacity of PLGA, serving as a solution to overcome the defects of a single material.…”