A photoelectrochemical sensor based on CdS-polyamidoamine nano-composite film for cell capture and detection.

We demonstrated herein a newly developed photoelectrochemical cell-sensor for the determination of SMMC-7721 human hepatoma carcinoma cells (SMMC-7721 cells) by using a photosensitive CdS-polyamidoamine (G4) nano-composite film (CdS-PAMAM). The film was generated by electrodeposition method. The presence of PAMAM in the film eliminated the surface defects of CdS nanoparticles and therefore resulted in a greatly enhanced photocurrent and a reduced dark current.

Molding a silver nanoparticle template on polydimethylsiloxane to efficiently capture mammalian cells.

Herein, a functional template made up of in situ synthesized silver nanoparticles (AgNPs) is prepared on polydimethylsiloxane (PDMS) for the spatial control of cell capture, where the residual Si-H groups in the PDMS matrix are used as reductants to reduce AgNO(3) for forming AgNPs. In virtue of microfluidic system, a one-dimensional array pattern of AgNPs is obtained easily. Further combining with plasma treatment, a two-dimensional array pattern of AgNPs could be achieved.

Thermal/plasma-driven reversible wettability switching of a bare gold film on a poly(dimethylsiloxane) surface by electroless plating.

We report an approach for fabricating a tunable wettability surface by electroless gold plating on poly(dimethylsiloxane) (PDMS). A two-layer structured gold film with a tight layer and a loose layer can be obtained on the surface of a PDMS chip when the PDMS chip is immersed in a gold plating solution at 30 degrees C for 4 h. Its wettability can be rapidly switched between superhydrophilicity and superhydrophobicity by plasma and heat treatments without any self-assembled monolayer, and the superhydrophobicity can be even changed from the gecko-foot-hair-like character to the lotus-leaf-like character.

Cytosensing and evaluation of cell surface glycoprotein based on a biocompatible poly(diallydimethylammonium) doped poly(dimethylsiloxane) film.

In this paper, we constructed an interface that not only retains viability of immobilized BGC823 human gastric carcinoma cells (BGC823 cells) but also efficiently resists nonspecific adsorption of the P-glycoprotein antibody and its secondary antibody, which enabled us to sensitively detect the number of cells and P-glycoproteins on the BGC823 cell surface by the immunoassay method. Preparation of the film was quite simple and inexpensive just by spin-coating poly(dimethylsiloxane) (PDMS) doped with poly(diallydimethylammonium) (PDDA) on the surface of gold electrodes. The composite film's biocompatibility, antinonspecific adsorption ability, and the conductivity for electrochemical probe ([Fe(CN)6]3-/4-) were proved by cell culture experiments, blocking experiments, and electrochemical experiments.

Patterned Au/poly(dimethylsiloxane) substrate fabricated by chemical plating coupled with electrochemical etching for cell patterning.

In this paper, we present a novel approach for preparing patterned Au/poly(dimethylsiloxane) (PDMS) substrate. Chemical gold plating instead of conventional metal evaporation or sputtering was introduced to achieve a homogeneous gold layer on native PDMS for the first time, which possesses low-cost and simple operation. An electrochemical oxidation reaction accompanied by the coordination of gold and chloride anion was then exploited to etch gold across the region covered by electrolyte.

[The spectroscopic studies on the binding of Al(III) to EHPG].

Interaction of ethylene-N,N'-bis(o-hydioxyphenylglycine) (EHPG) with Al3+ has been investigated by both UV difference and fluorescent spectra. Both results show that the molar ration of the complex is most likely 1:1. Aluminum binding produces peaks at 235 and 291 nm.