Cmos orca flash 4 lt camera

Microfluidic flow chambers were prepared as previously described.¹³ Briefly, the chambers were coated with a solution of fibrillary Horm collagen (200 µg/mL) overnight at 4℃ and blocked with phosphate buffered saline (PBS) 10 mg/mL human serum albumin for 30 minutes at room temperature. Hirudinated (100 U/mL) whole blood from healthy human volunteers was perfused through the coated capillaries with a syringe pump (Harvard Apparatus, Holliston, MA, USA) at 37℃ and various flow rates. Thrombus stability was studied in real time by differential interference contrast microscopy (Leica DMI4000B; Leica Microsystem, Mannheim, Germany) using a 40×, 1.25 numerical aperture oil objective and a Hamamatsu CMOS ORCA FLASH‐4 LT camera (Hamamatsu Photonics, Hamamatsu, Japan). For thrombus formation, whole blood was incubated with DIOC₆ (1 µM) to label platelets. Fluorescence emission was measured in the range of 490 to 595 nm after excitation with a 488‐nm argon‐ion laser using a confocal Leica SP8 inverted microscope with a resonant scanner and a 40× oil objective. Series of optical sections in xyz were taken from the base to the peak of the thrombi (Leica LAS X software). Images were then stacked and the volume of the thrombi was determined with ImageJ software (National Institutes of Health, Bethesda, MD, USA).