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signal was forwarded to a Voltage Input Module (NI-9215, NI) housed in a compactDAQ

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chassis (cDAQ 9171, NI). The device was queried by the NI-DAQmx library within a
custom-written Python 3 program.

Production and culture of scaffolded spheroids (S-SPHs)

96-, 384- and 1536-well plates were pre-filled with 200, 20 and 10 µL of deionized water,

respectively, using the automatic dispensing function in the controlling program.
Microscaffolds were then dispensed into each well. The plate was then centrifuged for 2

minutes at 200 x g to center the BBS in the wells of the plate. Water was evaporated at 60° C
on a heated plate for several hours. The well plates were then sterilized using the UV lamp in

the laminar flow cabinet and brought back to the sorting device to deposit 200, 20 or 10 µL of

cell-laden medium from a stock solution into each device.
The stock solution contained immortalized human adipose-derived mesenchymal stem cells

(hASC/hTERT; Evercyte, Austria), which were expanded using EGM™-2 BulletKit™
medium (Lonza, Switzerland) supplemented with 10% (v/v) newborn calf serum (NBCS;

Gibco, New Zealand) and maintained at standard culturing conditions (37° C, 5% CO2,
humidified atmosphere). The concentration of the stock was adjusted to deliver either 1000 or

5000 cells in the required working volume of the well plate. Spheroids were maintained for a

cultivation period of 12 days, with the culture media changed every 2-3 days. The spheroids
were imaged after 24 h and after 11 days using an optical microscope to evaluate for spheroid

formation.

Metabolic Activity Analysis

Metabolic activity was evaluated using PrestoBlue assay (A13261, Invitrogen). After either

automatically or manually depositing cells, 10 µL of the agent was added to 90 µL of already
deposited medium volume and left to react for 24 h under standard culture conditions.

Fluorescence was read out via a plate reader at an excitation of 570 nm and an emission of 590
nm. The fluorescence was normalized to the actual number of deposited cells derived from a

diluted standard Statistical Analysis

Unpaired t-test was performed to asses significance for p values < 0.05 and < 0.01 without
applying any corrections.

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