Biomedical subjects

Wanli Xing

Publications and source records attributed to Wanli Xing.

4 recordsLinked to original sources

PubMed2006

Microelectrode array-based system for neuropharmacological applications with cortical neurons cultured in vitro.

Microelectrode arrays (MEAs) provide a means to investigate the electrophysiological behavior of neuronal systems through the measurements from neuronal culture preparations. Changes in activity patterns of neuronal networks are usually detected by applying neural chemicals. Because of the difficulties of fabricating the arrays, and the delicate and less reliable properties of cortical neurons, MEA-based systems with cortical neuronal networks for neurophamacological applications are technically difficult, therefore restricting their utility. Here, we report a new approach to the development of such MEA-based system with sensitive and durable MEAs conveniently fabricated and the culture conditions optimized. Upon growth differentiation, cortical neurons, cultured directly on MEAs, reach a developmentally stable and reliable activity state. With this system, we monitored the global spontaneous activities of neuronal networks and demonstrated the fine discrimination for specific substances and unique property of cortical neurons, which validated both the applicability and necessity of such system in pharmacological bioassay.

Action Potentials↗

PubMed2006

Initial study of two-phase laminar flow extraction chip for sample preparation for gas chromatography.

A sample preparation method for gas chromatography using a two-phase, laminar flow extraction PDMS/glass chip has been developed. A stable two-phase laminar interface was obtained by surface modification, and the organic extraction phase and the aqueous sample phase were separated effectively when the two-phase laminar flows exit the chip. Experiments were conducted on the chip to extract ephedrine from aqueous solution. Good reproducibility was obtained over the entire range of ephedrine concentration using the extraction chips (CV range 2.7%-4.5%). Effects of salt and solvent on extraction efficiency were studied.

Chromatography, Gas↗

PubMed2005

Parallel detection and quantification using nine immunoassays in a protein microarray for drug from serum samples.

A protein microarray system for detection and quantification of nine prohibited drugs in serum is described. Chemically modified slides were chosen as the microarray substrates because of their suitable for drug-BSA printing. The developed protein microarray was able to preserve the biological function of the haptens, when immobilized on the microarray surface and demonstrated binding with their corresponding antibodies. The microarray could also be used for quantitative analysis when mouse IgG was chosen as an internal control for data processing. There was no qualitative difference between the results obtained using the protein microarray and ELISA. The protein microarray technology should be applicable to performing, simultaneously, large scale screening tests for many different analytes in serum.

Blood Chemical Analysis↗

PubMed2004

Negative dielectrophoretic force assisted construction of ordered neuronal networks on cell positioning bioelectronic chips.

Developing new methods and technologies in order to pattern neurons into regular networks is of utmost scientific interest in the field of neurological research. An efficient method here is developed for trapping neurons and constructing ordered neuronal networks on bioelectronic chips by using arrayed negative dielectrophoretic (DEP) forces. A special bioelectronic chip with well defined positioning electrode arrays was designed and fabricated on silicon substrate. When a high frequency AC signal was applied, the cell positioning bioelectronic chip (CPBC) is able to provide a well-defined non-uniform electric field, and thus generate negative DEP forces. The parameters, such as size of positioning electrode, conductivity of working solution, amplitude and frequency of power signal and cell concentration, were investigated to optimize the performance of the CPBC. When the neuron suspension was added onto the energized bioelectronic chip, the neurons were immediately trapped and quickly formed the predetermined pattern. Neurons may adhere and then be cultured directly on the CPBC, and show good neuron viability and neurite development. The formation of the ordered neuronal networks after two-week culture demonstrates that negative dielectrophoretic force assisted construction of ordered neuronal networks is effective, and it could be used to assist in monitoring functional activities of neuronal networks.

Animals↗