This research aimed to develop a procedure to optically trap organic solvents in the form of  microdroplet and to evaluate its optical stiffness based on the corner frequency, ??. The selected organic solvents were 1,2-dichlorobenzene, acetonitrile, chloroform, ethanol,  ethyl acetate and toluene. Microdroplets in water solution were prepared by ultrasonication for 2  minutes. Microdroplets in the range of 2 to 3 µm in diameter were then trapped by using 915 nm  laser at power densities of 6.3, 7.4 and 8.4 MW/cm² with laser spot size 1.1 µm. A quadrant  photodiode (QPD) was used to collect the scattered light from the single trapped microdroplet. The  signal was analysed using custom made software  named  OSCal  to  determine  ??  of  the  optical   trap.  The  results  showed  that 1,2-dichlorobenzene,  chloroform  and  toluene  formed  stable   microdroplets  in  water. Thus, these microdroplets can be optical trapped. The optical stiffness  .....

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