ABSTRACT
@#Objective To develop a colloidal gold immunochromatographic test strip for rapid and accurate detection of Pseudomonas aeruginosa(P.aeruginosa,Pa).Methods After bioinformatics analysis of Pa outer membrane protein OprF,the gene sequence with abundant antigenic determinants and high intraspecific homology was chemically synthesized,and then connected to pET-28a(+)vector to construct the expression vector pET-28a-OprF,which was transformed into E.coli BL21(DE3)and induced by IPTG. The recombinant OprF protein was purified by Ni Sepharose~(TM)6 Fast Flow and used to immunize two female BALB/c mice for 3～4 times by multi-point subcutaneous injection in the back at the first immunization and intraperitoneal injection at subsequent immunizations. The monoclonal antibodies were screened by animal cell fusion technique,and the colloidal gold immunochromatographic test strip for rapid detection of Pa was prepared by using monoclonal antibody and double antibody sandwich immunochromatography technique. The specificity,sensitivity and stability of the test strip were evaluated.Results Two monoclonal antibodies,Pa-1# and Pa-2#,were obtained with the titer of 1∶409 600,and both of them recognized OprF specifically. The prepared colloidal gold immunochromatographic test strip showed a sensitivity of 1. 0×10~6CFU/mL and had no cross reaction with 9 common respiratory pathogens with a good stability.Conclusion The prepared colloidal gold immunochromatographic test strip can detect Pa rapidly within 15 min,with high specificity and good stability.
ABSTRACT
Objective To research and develop the immunochromatographic detection technology of upcon-verting nanoparticles(UCNP)-based rapid fluorescence quantitative procalcitonin (PCT ) detection .Methods UCNP (NaYF4 :Yb3+ ,Er3+ ) was prepared by solvothermal method ,which was the compound of rare earth yt-terbium and erbium with four fluorine sodium yttrium .UNCP was conducted the modification and silica (SiO2 ) packing by using the reverse microemulsion method .Then the PCT determination method was estab-lished by using the dry-type immunochromatographic technology .Results The water-soluble UCNP with good dispersibility was successfully prepared by using the reverse microemulsion method .The lowest detection limit for detecting PCT by UCNP-based dry-type immunochromatographic technology was 0 .02 ng/mL ,the linear range was 0 .05 -44 .00 ng/mL ,the intra-batch and inter-batch coefficients variable(CV) were <10％and 13％ respectively .Conclusion UCNP-based immunochromatography technology is a rapidly and sensitively effective method for quantitatively detecting serum PCT .
ABSTRACT
A fluorescent immunochromatographic test strip based on the quantum dots submicrobeads (QBs) was developed for quantitative detection of chloramphenicol (CAP). In this method, monoclonal antibody of CAP and OBs complex fluorescent probe was first prepared using 1-ethyl-3-( 3-dimethylaminopropyl ) carbodiimide / N-hydroxysuccinimide coupling approach, then complete antigen CAP-HS-BSA was synthesized and sprayed on nitrocellulose membrane as test line (T line). Similarly, goat anti-mouse antibody was sprayed as control line (C line). The time required for the analysis was 15 min, and the limit of detection (LOD) for CAP was 0. 1 μg / L, with a working range of 0. 1 - 100 μg / L. In spiked milk samples, the test strip demonstrated high recoveries in the range from 93. 3% to 97. 9% with relative standard deviations of less than 7% .