Fig. 1: Diagram of microneedle apparatus (MA) for dermal ISF extraction from rats.
From: Immunization with VLP-based vaccines induces high IgG antibody titers in dermal interstitial fluid
MAs are 3D printed to hold five ultra-fine nano PEN needles such that 1500 µm of the needle protrudes from the bottom of the array and penetrates the dermis. Five microliters calibrated capillary tubes are placed on the needles inside the MA. MAs are lightly clamped onto the abdomen using 16 mm tissue forceps until at least 10 µL of fluid is collected. ISF samples are visually monitored for blood contamination. Pure ISF samples are transparent to pale yellow; any samples with RBCs present are discarded. Following sample collection, hemoglobin contamination was assessed spectrophotometrically. Created with BioRender.com.
