The addition of propranolol induced the aggregation of gold nanoparticles, and increased Rayleigh light scattering (RLS) intensity greatly. The interaction between them was studied by RLS spectrum, UV-Vis spectrum and transmission electron microscopy (TEM). Based on these results, a novel method was proposed for propranolol assay. With the combination of solid phase microextraction (SPME), the proposed method was successfully applied to determine propranolol in urine.
The purpose of this study was to develop a protein chip technique based on receptor binding assays to measure bioavailable serum sex hormone levels (BSSHL). 224 aging healthy Chinese were investigated to get the referenced values of BSSHL for the first time. In the assays recombined sex hormone receptor proteins were jointed to polysaccharide coated slides to make protein chip, and the dose-dependence curves of sex hormone on chip were prepared. The data showed that this method had good precision (CV<16%) and accuracy (Bias<10%), and the sensitivity could reach 1 pmol/L. From the results, BSSHL of men and women declined with aging, but no significant differences were observed. The BSSHL of aging men were higher than those of women. The bioavailable serum androgen level of men was 52―112 pmol/L, women's was 3―70 pmol/L and the whole group was 41.9―81.4 pmol/L. The bioavailable serum estrogen level of men was 0.8―3.0 pmol/L, women's was 1.2―2.5 pmol/L and the whole group was 0.6―2.64 pmol/L. Based on the assays, BSSHL measurement by protein chip can meet the needs of epidemiological studies in terms of speed, accuracy and sample volume required, and was helpful in quantitative assessment of aging people's health.
ZHOU Yong, CHANG Shuying, MENG Xiaoluo, YU Huafeng, WANG Luning, HE Jinggui, ZHANG Baohe, ZHANG Juntian, GENG Meiyu & DU Guanhua Institute of Marine Drugs and Food, Ocean University of China, Qingdao 266003, China
This paper describes a novel method in which solvent microextraction（SME） is followed by on-line back-extraction-field amplified sample injection（OLBE-FASI） in capillary zone electrophoresis（CZE）.The water-immiscible solution sample, sealed with water plug in the sample vial,was used for direct electroinjection. The water plug with moderate content of organic solvent,low-conductivity,and the presence of a small（amount） of H+ provided the highest sensitivity for analyzing positively chargeable compounds,such as cocaine and thebaine.The linear range was 0.040—4,0.040—2 μg/mL,with the square of the correlation coefficient(r2)>0.997,respectively.Detection limits were in the range of 5—10 ng/mL.
