Establishment of a New Method for Genetic Transformation of Dunaliella salina

The exogenous gene was integrated into Dunaliella salina successfully by using LiAc/PEG mediating method for the first time. According to the results of histochemical staining, transgenic D. salina was blue, showing that the exogenous GUS gene was successfully expressed in the cells of D. salina. Meanwhile, the effects of growth state of D. salina, plasmid concentration and temperature on its transformation efficiency were studied, and the transformation conditions were optimized. The results show that the optimum conditions for the genetic transformation of D. salina are shown as follows： D. salina was in the early logarithmic phase; plasmid DNA concentration was 600 μg/ml; temperature was 29 ℃, and transformation efficiency was up to 74.8‰ under the best conditions. According to the results of PCR amplification and PCR-Southern hybridization, the target gene had been integrated into genome and was hereditary.

Engineering miniature gold nanorods with tailorable plasmonic wavelength in NIR region via ternary surfactants mediated growth

Plasmonic nanoparticles are endowed profound capability for sensing,biomedicine,and cancer therapy.However,the inaccessibly adjustable wavelength in near infrared(NIR)region window and size limit for the particles penetration in tumor strongly hinder their developments.Miniature gold nanorods(mini-Au NRs)with diameter less than 12 nm can effectively address this challenge due to the tiny size and tailorable NIR absorption.Herein,we adopt ternary surfactants(hexadecyl trimethyl ammonium bromide(CTAB),sodium oleate(NaOL),and sodium salicylate(NaSal))mediated growth strategy to precisely synthesize miniature Au NRs under micelle space-confinement.Importantly,the selectively dense accumulation of ternary surfactants can efficiently improve the micellar stacking parameters(p)and lower micellar free energy(F),further tends to achieve the formation of Au NRs with tiny diameter and high purity.Compared with that of conventional methods,the purity of mini-Au NRs up to 100%can be dramatically improved via varying the relative concentration of ternary surfactants.The diameter of Au NRs can be dynamically controlled to 6,8,and 11 nm through regulating the concentration of silver nitrate and the mole ratio of ternary surfactants.Such ternary surfactants system is favorable for the aging of tiny Au NRs,and further enables the aspect ratio-tunable in the region from 2.70 to 7.32,as well as tailorable plasmonic wavelength in wide NIR window from 700 to 1,147 nm.Therefore,our findings shed a light on the precise preparation of small sized plasmonic nanoparticles and pave the way to applications in biomedicine,imaging,and cancer therapy.

Luminescence properties of Eu^(3+):NaGd(WO_4_)2 nanoparticles and nanorods

The NaGd(WO4)2:Eu3+ phosphors were prepared by the microemulsion mediated hydrothermal method. The morphology and size of the samples could be dependent on the pH in the initial solution. These phosphors obtained had a strong absorption at 395 nm matching with the popular emission of near-UV LED chips, and could emit intense red light at 616 nm. The small ellipsoid-like particles or short rods were provided with large parameters of oscillator strength?2 and asymmetry ratio. Compared to the ellip-soid-like phosphors, the rod-like phosphors took on stronger emission, longer lifetime and larger quantum efficiency. This work demonstrated that the one-dimension NaGd(WO4)2:Eu3+ phosphors might be a more favorable device than zero-dimension ones for photoluminescence.