Continuous Quadrupole Magnetic Separation of Islets during Digestion Improves Purified Porcine Islet Viability

Figure 2

QMS improves islet morphology and viability. (a) Representative magnified images of islets stained with dithizone immediately following isolation purified using (left) density gradients (DGs) or (right) quadrupole magnetic separation (QMS). At higher magnification, it is easy to appreciate the improved gross morphology of islets purified by QMS. Islets purified using QMS noticeably exhibit a more robust appearance, with larger sizes, more defined borders, and less free single cells. Islets purified using DGs frequently have a more fragmented appearance, with smaller size and rough borders. (b) Islet morphology scores determined immediately following isolation and purification. Islets purified by quadrupole magnetic separation (QMS) show improved morphology scores compared to traditional density gradient purified islets. Higher scores indicate better islet shape, borders, integrity, and diameter along with reduced presence of single cells. The sample size is small, so the difference is not significant; however, QMS purified islets exhibited a better score for all three paired islet isolations. (c) Graph presenting the measured viability of islets purified using density gradients (DGs) or quadrupole magnetic separation (QMS) immediately following isolation. QMS purified islets have a significantly higher viability ( indicates ) than DG purified islets immediately after isolation.

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