Preparation and quantitative analysis of multicenter luminescence materials for sensing function.

Luminescent sensing materials are attractive for environmental analysis due to their potential for high selectivity, excellent sensitivity and rapid (even instantaneous) response towards targeted analytes in diverse sample matrices. Many types of analytes have been detected in samples of wastewater for environmental protection, reagents and products in industrial production of drugs and pesticides, and biological markers in blood and urine for early diagnosis. It is still challenging, however, to develop appropriate materials with optimal sensing function for a targeted analyte. Here we synthesize metal-organic frameworks (MOFs) bearing multiple luminescent centers, such as metal cations (for example, Eu3+ and Tb3+), organic ligands and guests, which are chosen for optimal selectivity for the analytes of interest, including industrial synthetic intermediates and chiral drugs. Interaction between the metal node, ligand, guest and analyte results in a complex system with different luminescence properties compared with the porous MOF on its own. The operation time for the synthesis is usually less than 4 h; the quick screening for sensitivity and selectivity takes ~0.5 h and includes steps to optimize the energy levels and spectrum parameters. It can be used to accelerate the discovery of advanced sensing materials for practical applications.

[Studies on the growth of rabbit skin fibroblasts on the surfaces of acellular dermal matrix].

The growth of fibroblasts on the acellular dermal matrix (ADM) was studied. The fibroblasts isolated from the skin of an adult New Zealand Rabbit were cultured in vitro and identified subsequently. After the cells were inoculated on the ADM as seeds, the adhesion rate and the growth ability were examined, and cellular morphology was assayed with DAPI fluorescent staining and Scanning electron microscope (SEM). The possibilities of applying ADM as cells carrier or deliverer in the field of transplantation were evaluated. The result revealed that pure fibroblasts were isolated through the specific method. Skin fibroblasts could adhere to ADM easily, and the adhesion rate was 96.78%, displaying no significant difference (P > 0.05) when compared with that rate of the control holes. The cells on the scaffolds and those on the control holes showed similar growth tendencies, but the activity of the former was lower (P < 0.01). The integral nucleus with blue fluorescence could be observed on the ADM under fluorescence microscope. The number of fibroblasts scaled up with the cultured time, The results of SEM showed that the state of cell was good and the fibroblasts were fused into a layer after being cultured for 5-10d. So rabbit fibroblasts can attach, survive, grow and proliferate on the ADM in a healthy way. It is entirely possible to use ADM as an appropriate scaffold material for the culture of fibroblasts and as a material for transplantations.

[Konjac glucomannan-collagen -chitosan blend films (I)].

Konjac glucomannan-collagen-chitosan blend films were prepared successfully by the solvent-casting method and were characterized by FT-IR,X-ray diffraction, SEM and optical transmittance. Moreover, tensile strength, breaking extension, water absorption, water vapor permeation coefficients, adsorbability and penetrating rates were measured. The results indicated that some strong interaction and good compatibility existed among Konjac glucomannan /collagen and chitosan in the blend films. Some properties of the KCCS films were improved markedly in comparison with binary blend films or Konjac glucomannan, collagen and chitosan film. The results of culturing vessel endothelial cells on CKCS-5 film showed that the blend films have good cell compatibility which indicates the potential for a scalfold material in tissue engineering.

[Restoring the skin from traumatism by means of collagen-konjac glucomannan-chondroitin sulfate blend film].

This study aims at restoring the skin from traumatism by use of the collagen(from piglet skin) and konjac glucomannan-chondroitin sulfate blend film. The 2 cm x 4 cm skin traumatism model was established on both sides of the waist spinal column in 14 New Zealand rabbits each weighing 1.5-2.0 kg. One side was covered with blend film, the other side was used as a control. Then the changes of the skin traumatism were observed at different time-points after the operation, the wound tissue samples were taken for histological examination. The blend film could prevent skin traumatism from bleeding and infection. The skin traumatism treated by blend film showed signs of rectangle scab and the control showed signs of linear scab after healing. No obvious immune rejection was seen. The collagen-konjac glucomannan-chondroitin sulfate blend film can accelerate the restoration of skin from traumatism.

[Study on degradable properties of 3D-SC artificial skin in vitro].

OBJECTIVE: To study the degradable properties of 3D-SC artificial skin in vitro. METHODS: The 3D-SC artificial skin materials were respectively immersed into the solutions of 0.9% normal saline (control group), pancreatic tissue liquid (experimental group 1), physiological buffer (Hanks balanced salt solution,experimental group 2) and 0.2 mol/L phosphate buffer (pH 7.4, experimental group 3), and the degradation was carried out at 37 degrees C. The quality lost ratios were determined on the 3rd day, the 5th day, the 7th day, the 9th day, 11th day and 14th day in the experimental group 1, while on the 3rd day, 7th day, 14th day, 15th day, 21st day and 30th day in the other groups. RESULTS: The 3D-SC artificial skin was degraded completely in pancreatic tissue liquid about within 14 days in the experimental group 1; in the control group, and in the experimental groups 2 and 3, the degradation ratios were 8.68% +/- 2.30%, 28.51% +/- 10.68% and 7.35% +/- 0.61% on the 14th day; 71.83% +/- 2.58%, 91.32% +/- 1.87% and 75.64% +/- 6.13% on the 15th day, being significant difference between the control group and the experimental group 2 (P < 0.01); and 91.87% +/- 8.15%, 95.62% +/- 1.36% and 92.10% +/- 2.26% on the 30th day, being no significant differences between these 3 groups(P > 0.05), respectively. CONCLUSION: The 3D-SC artificial skin materials have good degradable properties. The trend of degradation speed is from slow to quick and then to slow without enzyme.

[Study status of collagen-based biomaterials in drug release and tissue engineering].

OBJECTIVE: To introduce the development of the collagen materials in drug release and tissue engineering. METHODS: Literature review and complex analysis were adopted. RESULTS: In recent years, some good progress has been made in the studies of collagen, and study on collagen-based materials has become an investigative hotspot especially in tissue engineering. Some new collagen-based drug delivery and engineered materials have come into clinically-demonstrated moment, which will promote their clinical applications in tissue repairs. CONCLUSION: Collagen has been considered a good potential material in drug release, especially in the tissue-engineering field. To give collagen new characters we should pay more attention to grafting with different function branches through chemistry technique in the future work, except moderate cross-linking treatment or commingling with other nature or synthesized macromolecules.