AU - Abbasi Ahd, Atefeh AU - kargosha, kazem AU - Madarshahian, Sara AU - Shokoufi, Nader TI - Online Monitoring of Gold Nanoparticles by Photothermal Lens Microscopy PT - JOURNAL ARTICLE TA - opsi JN - opsi VO - 21 VI - 0 IP - 0 4099 - http://opsi.ir/article-1-795-fa.html 4100 - http://opsi.ir/article-1-795-fa.pdf SO - opsi 0 AB  - In this paper, we have developed an inverted photothermal lens microscope with a flow through optical cell to detect the gold nanoparticles (AuNPs) prepared by trisodium citrate reduction. The measurements were made using a continuous-wave excitation (wavelength, 532 nm) and probe laser beams (wavelength, 652 nm).The changes in the transmitted probe beam’s center intensity were detected with a photodiode. The indirect detection of the plasmonic signals of AuNPs was done by using thermal lens phenomena. The results show the possibility of online determination of AuNPs in micro and nano volume in the range of 1.6-6.4 particles per the focal volume of the excitation beam. The irreproducibility of AuNPs’s thermal lens signal in water is eliminated by increasing in the modulation frequency of excitation beam and employing flow optical cell with an optimum flow velocity of sample injection. CP - IRAN IN - LG - eng PB - opsi PG - 1667 PT - Research YR - 2015