H. C. Yang

Kun Shan University, 臺南市, Taiwan, Taiwan

Are you H. C. Yang?

Claim your profile

Publications (250)367.64 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Nanomagnetically labeled immunoassays have been demonstrated to be promisingly applied in clinical diagnosis. In this work, by using antibody-functionalized magnetic nanoparticles and a high-temperature superconducting quantum interference device ac magnetosusceptometer, the assay properties for vascular endothelial growth factor (VEGF) in serum are investigated. By utilizing the assay method so-called immunomagnetic reduction, the properties of assaying VEGF are explored. In addition, the VEGF concentrations in serum samples of normal people and patients with either colorectal or hepatocellular cancer are detected. The experimental results show that the low-detection limit for assaying VEGF is 10 pg/mL, which is much lower than the clinical cut-off VEGF concentration of 50 pg/mL for diagnosing malignancy. Besides, there are no significant interference effects on assaying VEGF from hemoglobin, conjugated bilirubin, and triglyceride. The VEGF concentrations in serum samples donated by normal people and patients with hepatocellular carcinoma or colorectal cancer are detected. A clear difference in VEGF concentrations between these two groups is found. These results reveal the feasibility of applying nanomagnetically labeled immunoassay to clinics.
    Journal of Nanomaterials 10/2013; 2013. · 1.55 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The in-plane longitudinal and Hall resistivities, ρxx and ρxy, of superconducting NaFe1-xCoxAs (NFCA) single crystals with x = 0.022 and 0.0205 in the mixed state and the normal state were measured to study the electrical transport properties in nearly optimum-doping iron-based superconductors. The resistivities under magnetic fields show thermally activated behavior and a power law magnetic field dependence of activation energy has been obtained. Due to the weak flux pinning, there is no sign reversal of Hall resistivities observed for NFCA with either x = 0.022 or 0.0205. The correlation between longitudinal and Hall resistivities shows that the scaling behavior of |ρxy| ∝ (ρxx)(β) with the exponent β ≈ 2.0 is in agreement with theoretical predictions for weak-pinning superconductors. Anisotropic upper critical fields and coherence lengths with an anisotropy ratio of γ ≈ 1.63 have been deduced. Furthermore, the normal-state transport properties show that the anomalies of the linear-T resistivity, the T(2)-dependent cotangent of the Hall angle, the linear-T-like Hall number, and the magnetoresistance, which can be scaled by the modified Kohler rule, are analogous to those observed on optimally doped high-Tc superconducting cuprates and other pnictides. The longitudinal resistivity can be understood within a widely accepted scenario of the spin density-wave quantum critical point, while the transverse resistivity requires some further explanation. It is suggested that all the transport anomalies should be simultaneously taken into account when developing theory.
    Journal of Physics Condensed Matter 09/2013; 25(39):395702. · 2.22 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Immunomagnetic reduction assay is used to quantitatively detect bio-molecules. Many reports show that the to-be-detected bio-molecular concentration dependent reduction in the alternative-current (ac) magnetic susceptibility of a reagent is governed by the logistic function, which is a four-parameter function. One of the parameters relates to the increase in the rate of the magnetic reduction signal when the concentration of to-be-detected bio-molecules is increased. Theoretically, this parameter is attributed to the clustering associations between to-be-detected bio-molecules and labeling particles in the reagent. In an immunomagnetic reduction assay, the bioactive labeling particles are anti-body-functionalized magnetic nanoparticles. However, there is no detailed information about the effect of the clustering associations on this parameter. In this work, the clustering association is manipulated by controlling the concentrations of anti-body-functionalized magnetic nanoparticles in the reagent. The experimental results show that higher values for this parameter are obtained with concentrated anti-body-functionalized magnetic nanoparticles in the reagent. This implies that particle clustering is enhanced by an increase in the concentration of the bio-functionalized magnetic particles. It is also demonstrated that the particle clustering effect dominates the increased rate of the magnetic reduction signal.
    Journal of Applied Physics 04/2013; 113(14). · 2.21 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: In this work, the spin-spin relaxation rate, 1/T2, and spin-lattice relaxation rate, 1/T1, of protons’ spins induced by biofunctionalized magnetic nanoparticles and ferrofluids are investigated using a high-Tc superconducting quantum interference device-detected magnetometer in ultra-low fields. The biofunctionalized magnetic nanoparticles are the anti-human C-reactive protein (antiCRP) coated onto dextran-coated superparamagnetic iron oxides Fe3O4, which is labeled as Fe3O4-antiCRP. The ferrofluids are dextran-coated iron oxides. It was found that both 1/T2 and 1/T1 of protons in Fe3O4-antiCRP are enhanced by the presence of magnetic nanoparticles. Additionally, both the 1/T1 and 1/T2 of Fe3O4-antiCRP are close to that of ferrofluids, which are dextran-coated Fe3O4 dispersed in phosphate buffer saline. Characterizing the relaxation of Fe3O4-antiCRP can be useful for biomedical applications.
    Journal of Applied Physics 01/2013; 113(4). · 2.21 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: In this paper, we report an enhanced liver tumor discrimination for rats using antibody-activated magnetic nanoparticles (MNs) and ultra-low-field magnetic resonance imaging ex vivo. It was found that the intensity ratio between the magnetic resonance image of tumor and normal liver tissues is 2–3 absence of antibody-activated MNs in rats. The intensity ratio rises to ∼100 when antibody-activated MNs are expressed in liver tumors through vein injection. Enhancing tumor discrimination using antibody-activated MNs is demonstrated using T1-weighted contrast imaging in ultra-low magnetic fields.
    Applied Physics Letters 01/2013; 102(1). · 3.52 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In this work, the time-dependent phase lag θ of biofunctionalized magnetic nanoparticles (BMNs) conjugated with biotargets is studied with a home-made alternating current (ac) susceptometor for liquid phase immunoassays. The sensing unit of the ac susceptometor composed of excitation, pick-up, and compensation coils are balanced to 0.03 ppm. The BMNs are anti-goat C-reactive protein coated onto dextran-coated magnetic nanoparticles composed of Fe3O4, labeled as Fe3O4-antiCRP. The bio-targets are human CRP. As the human CRP is conjugated with reagents Fe3O4-antiCRP, the magnetic clusters of Fe3O4-antiCRP-CRP are formulated. Due to the clustering effect, the Brownian relaxation of BMNs will be depressed, which in turn enhances the effective relaxation time. By monitoring the dynamic phase lag, we demonstrate a sensitive platform of assaying human CRP. The detection platform is robust, easy to use and can be applied for assaying a wide variety of biotargets including viruses, proteins, tumor markers, chemicals, etc.
    Applied Physics Letters 01/2013; 103(24):243703-243703-5. · 3.52 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: To image magnetic nanoparticles (MNPs) on animal bodies, physicians often use magnetic resonance imaging to determine the superparamagnetic characteristics of MNPs during preoperative analysis. However, magnetic resonance imaging is unsuitable for other biomedical applications, such as the curative surgical resection of tumors or pharmacokinetic studies of MNPs, because of the requirement of nonmetal environments and high financial cost of frequent examination, respectively. Thus, researchers have proposed other nonmagnetic imaging technologies, such as fluorescence, using multimodal MNPs with nonmagnetic indicators. The development of a magnetic instrument based on the other magnetic characteristics of MNPs avoids the disadvantages of multimodal MNPs, including the biosafety risk. On the basis of the alternating current susceptibility of MNPs, previous research has demonstrated the magnetic examination of scanning superconducting-quantum-interference-device biosusceptometry (SSB). This study, using a low-noise charge-coupled-device type of a video camera, reports the integration of SSB and charge-coupled-device to immediately image the magnetic signals on animal bodies or organic tissue. This real-time imaging by SSB increases the usefulness of MNPs for more clinical applications, including the imaging-guided curative surgical resection of tumors.
    IEEE Transactions on Applied Superconductivity 01/2013; 23(3):1601503-1601503. · 1.20 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The HTS superconducting quantum interference devices (SQUID) magnetometers meets the requirement for the early-stage or hard-to-detect in-vitro diagnosis because of its ultrahigh sensitivity. For example, the demand for assaying the ultra-low-concentration biomarkers of tumors is always existing. It would be better to quantitatively detect the vascular endothelial growth factor (VEGF) at the concentration of 1 pg/ml for diagnosing the early-stage malignancy. In this work, by using the HTS SQUID-based ac magnetosusceptometer and biofunctionalized magnetic nanoparticles, the low-detection limit for VEGF is sub-pg/ml. Furthermore, the clear difference in the VEGF concentrations in sera was found between normal people and tumor patients. Another example to demonstrate the high sensitivity and high specificity of the immunoassay based on the HTS SQUID ac magnetosusceptometer is the detection of biomarkers for Alzheimer's Disease. The biomarkers for Alzheimer's Disease in plasma are very rare (around 1-100 pg/ml). It is hardly possible to assay the biomarkers in plasma. Here, it has been demonstrated that the HTS SQUID ac magnetosusceptometer can detect the biomarkers at very low concentrations ( ~ 1 pg/ml). Through the assays on the biomarkers in plasma of more than 100 people, the clinical accuracy is almost 90%. These results show the niches of clinical applications using the HTS SQUID ac magnetosusceptometer.
    IEEE Transactions on Applied Superconductivity 01/2013; 23(3):1600604-1600604. · 1.20 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Although there is a consensus on the reduced levels of Aβ1-42 in the CSF of patients with AD, studies of plasma Aβlevels were inconsistent and have limited clinical value. We developed an immunomagnetic reduction assay (IMR) to determine the plasma levels of Aβ.We surveyed patients with varying AD severity (CDR = 0.5, n=16; CDR ≥1, n=18) and controls (n=26). Significant group differences were apparent in the levels of Aβ1-42 (F = 5.54, p = 0.002) and the Aβ1-42/Aβ1-40 ratio (F = 24.198, p <0.001). Post-hoc analyses showed significant differences in the Aβ1-42 levels of controls and AD patients (p = 0.001) and in the Aβ1-42/Aβ1-40 ratio of control, MCI and AD subjects (all p ≤0.001). Regression analysis of Aβ1-42/Aβ1-40 ratios on dementia severity showed an adjusted R2 of 0.553 (p = 0.001).We identified a cut-off of 16.1 pg/ml for Aβ1-42 to differentiate control subjects from patients (both AD and MCI) with 85.3% sensitivity and 88.5% specificity. We also obtained a cut-off value of 0.303 for Aβ1-42/Aβ1-40 ratios with 85.3% sensitivity and 96.2% specificity. APOE ε4 carriers had significantly higher Aβ1-42/Aβ1-40 ratios than the non-carriers (F = 4.839, p = 0.015). An independent group of case-control subjects validated both cut-off values for Aβ1-42/Aβ1-40 (100% sensitivity and 83.3% specificity) and for Aβ1-42 (100% sensitivity and 75.3% specificity). In a subgroup of longitudinal follow-up study, we found that the plasma Aβ was relatively stable with an interval of 3 approximately 3 months. In conclusion, we found that the plasma Aβ1-42 is a useful biomarker for AD. The Aβ1-42/Aβ1-40 ratio improves the diagnostic power of the plasma Aβ biomarkers. The iron nanoparticles and IMR provides a novel method to measure plasma Aβ and could serve as an important clinical tool for the diagnosis of neurodegenerative diseases.
    Current Alzheimer research 08/2012; · 4.97 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: By specifically bio-functionalizing magnetic nanoparticles, magnetic nanoparticles are able to label target bio-molecules. This property can be applied to quantitatively detect molecules invitro by measuring the related magnetic signals of nanoparticles bound with target molecules. One of the magnetic signals is the reduction in the mixed-frequency ac magnetic susceptibility of suspended magnetic nanoparticles due to the molecule-particle association. Many experimental results show empirically that the molecular-concentration dependent reduction in ac magnetic susceptibility follows the logistic function. In this study, it has been demonstrated that the logistic behavior is originated from the growth of particle sizes due to the molecule-particle association. The analytic relationship between the growth of particle sizes and the reduction in ac magnetic susceptibility is developed.
    Journal of Applied Physics 07/2012; 112(2). · 2.21 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The application of the assay methodology, called immunomagnetic reduction, using bio-functionalized magnetic nanoparticles as labeling markers for chloramphenicol was investigated. The reduction in the alternative-current (ac) magnetic susceptibility χac of magnetic nanoparticles caused by the association between magnetic nanoparticles and chloramphenicol was detected as a function of the concentration of chloramphenicol. In this study, the characterizations used to detect chloramphenicol, such as low-detection limit and interference, were also conducted. Furthermore, the extracting processes for chloramphenicol from shrimp were explored. Thus, the platform for detecting chloramphenicol residue in shrimp via immunomagnetic reduction was demonstrated. Such platform showed features of a 0.1-ppb low-detection limit, low interference from other kinds of antibiotics, and easy operation.
    Food Chemistry. 04/2012; 131(3):1021–1025.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Nervous necrosis virus (NNV) is the cause of viral nervous disease, which is a serious constraint on production for grouper aquaculture. Real-time PCR is commonly used to detect and quantify NNV, has the disadvantages of being expensive and technically demanding. In this study, an immunomagnetic reduction (IMR) assay was developed as a rapid and cost-effective alternative to real-time PCR. This method used magnetic nanoparticles conjugated with antibodies specific for viral surface antigens to detect NNV in grouper tissue samples. The association of NNV with the antibody-conjugated magnetic particles resulted in a reduction in magnetic signal, which was strongly correlated with the concentration of NNV, as determined by real-time PCR. Grouper larvae were prepared for testing using a viral extraction buffer which provided a rapid, 15-min method of extracting viral antigens and had an extraction efficiency of higher than 80%. In addition, this study proposes using magnetic nanoparticles as labeling markers and as an assaying reagent for NNV. The magnetic nanoparticles are functionalized with antibodies against the viral surface of NNV and are able to associate specifically with NNV. The reduction of the magnetic signals comes from the association between magnetic particles and NNV, and relates to the concentration of NNV. The results show that the detected concentrations of NNV are highly correlated to those detected by real-time PCR.
    Journal of virological methods 02/2012; 181(1):68-72. · 2.13 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Magnetic nanoparticles biofunctionalized with antibodies are useful for specifically labeling target biomolecules. By measuring magnetic signals after the association between biofunctionalized magnetic nanoparticles and target biomolecules, the concentration of target biomolecules can be quantitatively detected. One of measuring methodologies is so-called immunomagnetic reduction (IMR), in which the reduction in ac magnetic susceptibility of magnetic reagent is a function of the concentration of target biomolecules. In this letter, the relationship between the magnetic reduction signal of reagent and the concentration of target biomolecules is explored. According to the experimental results on various kinds of target biomolecules, such as proteins and chemicals, the magnetic reduction signal as a function of concentration of various target biomolecules can be scaled to a universal curve. This universal curve is a logistic function. This implies that there exists a unique mechanism for the association between the target biomolecules and biofunctionalized magnetic nanoparticles in an IMR assay.
    IEEE Magnetics Letters 01/2012; 3:1500104-1500104.
  • [Show abstract] [Hide abstract]
    ABSTRACT: This study presents a compound optical film to improve luminance and uniformity to apply in side-LED (light-emitting diode) backlight module. LIGA (lithographie galvanoformung abformung) technology, soft lithography, and homemade gray scale mask were combined to fabricate microlens array. Optical film with variable size microlens array embedded with microvoids was designed and manufactured. FRED software was used to simulate optical performance. Microvoids were quantitatively embedded in the PDMS (polydimethylsiloxane) optical film. Under the quantitative control of air pressure, those microvoids inside the optical film can cause light diffusion. The compound optical film with embedded microvoids, multiaspect ratio, and variable size microlens array can be fabricated quickly without substrate. Luminance colorimeter BM-7A from TOPCON was used to carry out the optical measurement. According to the measured data, the compound optical film with embedded microvoids can enhance the luminance up to 5% and the uniformity up to 6.5% ~ 8.4%. The optical efficiency can be improved via the compound optical film.
    Advances in Condensed Matter Physics 01/2012; 2012. · 1.18 Impact Factor
  • Source
    P. H.chang, H. C.yang, H. E.horng
    [Show abstract] [Hide abstract]
    ABSTRACT: A possible mechanism in the anomalous Hall coefficient in mixed state of high-Tc superconductors was presented in this paper. The Hall voltage due to flux creep is the origin of the observed Hall anomaly. The calculated Hall coefficient exhibits a sign change as well as a re-entry behavior, which agree with experiments, qualitatively.
    Modern Physics Letters B 11/2011; 14(25n26). · 0.48 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Via immunomagnetic reduction assay, bio-molecules can be quantitatively detected with the aid of bio-functionalized magnetic nanoparticles, which are used as labeling markers for specific bio-molecules. To achieve an ultra-high sensitivity in the detection of bio-molecules, the superconducting quantum interference device (SQUID) looks very promising as a sensor for the magnetic signal that are related to the concentration of the detected bio-molecules. We had developed a single channel SQUID-based magnetosusceptometer, but for increasing the detection through-put, we have developed a multi-channel SQUID-based magnetosusceptometer. In this work, the design and the working principle of a 4-channel SQUID-based magnetosusceptometer are introduced. By utilizing scanning technology, 4 samples can be logged into a SQUID-based magnetosusceptometer simultaneously. Be noted that only one single SQUID magnetometer has been used in the magnetosusceptometer. The precision and the sensitivity of detecting bio-molecules by using a 4-channel SQUID-based magnetosusceptometer have been investigated. The detected bio-molecules are biomarkers for Alzheimer's disease.
    IEEE Transactions on Applied Superconductivity 07/2011; · 1.20 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The fabrication processes for step-edge high- T<sub>c</sub> superconducting-quantum-interference-device (SQUID) magnetometers have been developed. A magnetometer consists of three SQUIDs, which can be activated either individually or in series. Thus, the transfer function can be manipulated by activating a single SQUID or multiple SQUIDs in series. Furthermore, such a SQUID magnetometer is benefited by that if one of the three SQUIDs is broken, the other two SQUIDs are still workable. In addition to characterizing the SQUID magnetometer, the application of the SQUID magnetometer in the low-field nuclear magnetic resonance (NMR) has also been investigated. The results has shown a clear NMR signal of 4230 Hz for the water under 99.3 μT.
    IEEE Transactions on Applied Superconductivity 07/2011; · 1.20 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: To determine the iron concentration of administrated magnetic nano-particles in animals is essential for evaluation of arrival efficiency in target regions in biomagnetism studies. In this work, a high T<sub>c</sub> superconucting quantum interference devices (SQUID) biosusceptometry with a scanning coil set is developed. The measurement principal is based on the AC susceptibility of magnetic nano-particles, and the low noise of 8 pT/√Hz at 400 Hz is characterized in unshielded environment. The dextran-coated magnetic nano-particle of 50 nm in diameter is administrated intravenously into Wistar male rats to demonstrate the in-vivo and fast examination feasibility of this instrument. The in-vivo results of heart region and liver region explained the reasonable biological phenomenon of magnetic nano-particles in animals. Good correlation of concentration-time curve between the induction-coupled-plasma (ICP) and in-vivo examination by AC susceptibility measurement in rat liver region until 4 hours after injection of magnetic naoparticle validates the in-vivo measurement of iron concentration. After 4 hrs post magnetic nanoparticle injection, the phagocyted magnetic nano-particles in liver tissue shows antiferromagnetism properties and explain the difference between the low in-vivo intensity by AC susceptibility measurement and high intensity by ICP.
    IEEE Transactions on Applied Superconductivity 07/2011; · 1.20 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Polycrystalline samples of HoxTb2-xTi2O7 (0 < x < 2) have been prepared and characterized for their structural and magnetic properties. The parent compounds of this solid solution are the spin ice Ho2Ti2O7 and the spin liquid Tb2Ti2O7. Specific-heat measurements on HoTbTi2O7 (x = 1.0) reveal the absence of a long-range order state above 0.5 K. The integrated entropies of all HoxTb2-xTi2O7 specimens up to 30 K scale well with the ratio of spin ice and spin liquid in the composition. The neutron diffraction spectrum of HoTbTi2O7 exhibits a dipolar spin-ice pattern and can be well described by mean-field theory for 〈111〉 Ising spins, nearest-neighbor exchange, and dipolar interactions. Inelastic neutron scattering on HoTbTi2O7 reveals two dispersionless excitations, one of ∼2.5 meV out of the ground state, and a 4-meV transition out of an excited state. We argue that these data suggest that the very strong single-ion effects of Ho2Ti2O7 and Tb2Ti2O7 persist in the HoxTb2-xTi2O7(0 < x < 2) solid solution, whereas the Tb-Ho correlations are weak, resulting in small shifts in the energy scales but with no dramatic effect on the bulk properties.
    Physical Review B 04/2011; 83(14). · 3.66 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Polycrystalline samples of HoxTb2-xTi2O7 (0 < x < 2) have been prepared and characterized for their structural and magnetic properties. The parent compounds of this solid solution are the spin ice Ho2Ti2O7 and the spin liquid Tb2Ti2O7. Specific-heat measurements on HoTbTi2O7 (x = 1.0) reveal the absence of a long-range order state above 0.5 K. The integrated entropies of all HoxTb2-xTi2O7 specimens up to 30 K scale well with the ratio of spin ice and spin liquid in the composition. The neutron diffraction spectrum of HoTbTi2O7 exhibits a dipolar spin-ice pattern and can be well described by mean-field theory for Ising spins, nearest-neighbor exchange, and dipolar interactions. Inelastic neutron scattering on HoTbTi2O7 reveals two dispersionless excitations, one of ˜2.5 meV out of the ground state, and a 4-meV transition out of an excited state. We argue that these data suggest that the very strong single-ion effects of Ho2Ti2O7 and Tb2Ti2O7 persist in the HoxTb2-xTi2O7(0
    Physical review. B, Condensed matter 01/2011; 83. · 3.77 Impact Factor

Publication Stats

1k Citations
367.64 Total Impact Points

Institutions

  • 2013
    • Kun Shan University
      臺南市, Taiwan, Taiwan
  • 2003–2012
    • National Sun Yat-sen University
      • • Department of Mechanical and Electro-Mechanical Engineering
      • • Department of Physics
      Kao-hsiung-shih, Kaohsiung, Taiwan
  • 1988–2011
    • National Taiwan Normal University
      • • Department of Electro-Optical Science And Technology
      • • Department of Physics
      Taipei, Taipei, Taiwan
    • National Taiwan University
      • Department of Physics
      Taipei, Taipei, Taiwan
  • 2008–2010
    • National Chung Hsing University
      • Department of Physics
      臺中市, Taiwan, Taiwan
  • 2009
    • Korea Research Institute of Standards and Science
      • Medical Metrology
      Seoul, Seoul, South Korea
    • Nan Kai University of Technology
      Nantow, Taiwan, Taiwan
    • Animal technology institute Taiwan
      T’ai-pei, Taipei, Taiwan
  • 2007
    • E-Da Hospital
      T’ai-pei, Taipei, Taiwan
  • 2005–2007
    • National Taipei University of Technology
      T’ai-pei, Taipei, Taiwan
    • Chung Yuan Christian University
      T’ai-pei, Taipei, Taiwan
  • 2006
    • National Chung Cheng University
      • Department of Physics
      Xinying, Taiwan, Taiwan
  • 1999–2006
    • Da-Yeh University
      T’ai-pei, Taipei, Taiwan
  • 1973–2006
    • Lehigh University
      • Department of Materials Science and Engineering
      Bethlehem, Pennsylvania, United States