Simultaneous detection of carcinoembryonic antigen and neuron-specific enolase in human serum based on time-resolved chemiluminescence immunoassay

We developed a novel, effective, reliable and convenient TRCLIA method for the simultaneous detection of CEA and NSE in serum.

Magnetic iron oxide modified pyropheophorbide-a fluorescence nanoparticles as photosensitizers for photodynamic therapy against ovarian cancer (SKOV-3) cells

Magnetic iron oxide modified pyropheophorbide-a fluorescence nanoparticles for photodynamic therapy against SKOV-3 cells.

Photo-fluorescent and magnetic properties of iron oxide nanoparticles for biomedical applications

Iron oxide exhibits fascinating physical properties especially in the nanometer range, not only from the standpoint of basic science, but also for a variety of engineering, particularly biomedical applications. For instance, Fe3O4 behaves as superparamagnetic as the particle size is reduced to a few nanometers in the single-domain region depending on the type of the material. The superparamagnetism is an important property for biomedical applications such as magnetic hyperthermia therapy of cancer. In this review article, we report on some of the most recent experimental and theoretical studies on magnetic heating mechanisms under an alternating (AC) magnetic field. The heating mechanisms are interpreted based on Néel and Brownian relaxations, and hysteresis loss. We also report on the recently discovered photoluminescence of Fe3O4 and explain the emission mechanisms in terms of the electronic band structures. Both optical and magnetic properties are correlated to the materials parameters of particle size, distribution, and physical confinement. By adjusting these parameters, both optical and magnetic properties are optimized. An important motivation to study iron oxide is due to its high potential in biomedical applications. Iron oxide nanoparticles can be used for MRI/optical multimodal imaging as well as the therapeutic mediator in cancer treatment. Both magnetic hyperthermia and photothermal effect has been utilized to kill cancer cells and inhibit tumor growth. Once the iron oxide nanoparticles are up taken by the tumor with sufficient concentration, greater localization provides enhanced effects over disseminated delivery while simultaneously requiring less therapeutic mass to elicit an equal response. Multi-modality provides highly beneficial co-localization. For magnetite (Fe3O4) nanoparticles the co-localization of diagnostics and therapeutics is achieved through magnetic based imaging and local hyperthermia generation through magnetic field or photon application. Here, Fe3O4 nanoparticles are shown to provide excellent conjugation bases for entrapment of therapeutic molecules, fluorescent agents, and targeting ligands; enhancement of solid tumor treatment is achieved through co-application of local hyperthermia with chemotherapeutic agents.

A novel HBV genotypes detecting system combined with microfluidic chip, loop-mediated isothermal amplification and GMR sensors

Genotyping of hepatitis B virus (HBV) can be used for clinical effective therapeutic drug-selection. A novel microfluidic biochip for HBV genotyping has been fabricated, for the first time, integrating loop-mediated isothermal amplification (LAMP), line probes assay (LiPA) and giant magnetoresistive (GMR) sensors. Coupling LAMP with LiPA in microfluidic chip shortened reaction time substantially, and combining LAMP with GMR sensor enabled limit of detection to attain 10 copies mL(-1) target HBV DNA molecules in 1 h. Furthermore, the independent designed GMR sensors and microfluidic chip can decrease manufacturing cost and patient's test-cost, and facilitate GMR detector repeating use for signal detection. In addition, the detection system has a lower background signal owing to application of superparamagnetic nanoclusters. And it can be expected to use for multiple target molecules synchronous detection in microfluidic chip based on a characteristic of stationary reaction temperature of LAMP. In conclusion, the neoteric detecting system is well suitable for quick genotyping diagnosis of clinical HBV and other homothetic biomolecule detection in biological and medical fields.

Quick genotyping detection of HBV by giant magnetoresistive biochip combined with PCR and line probe assay

Genotyping of human hepatitis B virus (HBV) can be used to direct clinically effective therapeutic drug-selection. Herein we report that a quick genotyping method for human HBV was established by a specially designed giant magnetoresistive (GMR) biochip combined with magnetic nanoclusters (MNCs), PCR and line probe assay. Magnetic nanoclusters of around 180 nm in diameter were prepared and modified with streptavidin, and resultant streptavidin-modified magnetic nanoclusters were used for capturing biotin-labeled hybrid products on the detection interface of the sensor. The gene fragments of HBV's B and C gene types were obtained by PCR based on a template of B- and C-type plasmids. After gene fragments were hybridized with captured probes, streptavidin-modified magnetic nanoclusters could bind with biotin-conjugated gene fragments, and the resultant hydride products could be quickly detected and distinguished by the GMR sensor, with a detection sensitivity of 200 IU mL(-1) target HBV DNA molecules. The novel method has great potential application in clinical HBV genotyping diagnosis, and can be easily extended to other biomedical applications based on molecular recognition.