of the matrix nanofiber was tailored by the polymer concentration and electrospinning speed next a leica laser microdissection 7000 leica microsystem germany will be used to generate tubular structure on the nanofibrous matrix the matrix will be tiled flat onto a glass coverslip a software leica laser microdissection v7 4 1 was used to design the pore distribution pattern during the laser ablation process the pore size was controlled by the laser aperture and laser pulse energy and the pore density was modulated by the laser frequency and speed for a typical experiment to generate the tubular architecture the operation parameters of the equipment are as follows laser aperture 30 hz laser pulse energy 30 hz laser speed 40 hz and laser pulse frequency 37 hz using these parameters more than 130000 tubular pores were created in each hour increasing the pulse frequency increased the number of pores generated in each unit time because the laser strength is the highest on the top surface of the matrix and the lowest on the bottom of the matrix an inverted cone like structure of each cylindrical pore will be created during the laser ablation process one advantage of using this technology is its capability to precisely relocate to its previous position therefore the ablation process can be repeated multiple times to ensure that each pore in the matrix is open to prepare tubular matrix with different pore sizes and densities optimization of the matrix the.