Crude firefly lanterns

Materials for the Stratasys J750 PolyJet printer (VeroClear, MED610, and Tango+) were obtained directly from Stratasys (Eden Prairie, MN). ATP, crude firefly lanterns, HBSS, tris (hydroxymethyl)-aminomethane, CaCl₂, NaCl, Mg(SO₄), glucose, and glycerol were obtained from Sigma-Aldrich (St. Louis, MO). Luciferin was obtained from GoldBiotechnology (St. Louis, MO). KCl was obtained from Fisher Scientific (Fair Lawn, NJ). Bovine serum albumin was obtained from MP Biomedical.

3D-printer materials for the Stratasys J750 PolyJet printer were obtained directly from Stratasys (Eden Prairie, MN). Fluorescein, ATP, crude firefly lanterns, tris(hydroxymethyl)-aminomethane, CaCl₂, NaCl, MgSO₄, glucose, chloroplatinic acid, lead (II) acetate, Nafion, glybenclamide, L-NAME (N-Nitro-L-arginine methyl ester), D-mannitol, adenine, and phosphate buffered saline (10x) were obtained from Sigma-Aldrich (St. Louis, MO). Luciferin was obtained from Gold Biotechnology (St. Louis, MO). KCl was obtained from Fisher Scientific (Fair Lawn, NJ). Bovine serum albumin was obtained from MP Biomedical (Irvine, CA). Argon and NO gas were supplied by AirGas (Radnor, PA). The platinum and gold electrode materials were obtained from Alfa Aesar (Haverhill, MA). Oxyrase came from Oxyrase, Inc. (Mansfield, OH).

To show the possibility of subsequent downstream detection (post-amperometry), the device design was altered to include a separate port for reagent addition and a channel for mixing and chemiluminescent detection of ATP (Figure 4A-B). A second input for reagent was added at a 90° angle to the channel and the output channel extended to form a mixing T and a reaction and detection channel. ATP detection occurred via the luciferin-luciferase assay as previously reported.^{22 (link)} For this assay, 50 mg of crude firefly lanterns (Sigma-Aldrich, St Louis, MO) and 3.2 mg of D-luciferin (Gold Biotechnology, St. Louis, MO) were dissolved in 10 mL of PBS and sterile-filtered. A syringe pump was used to continuously pump reagent through the device at 15 μL/min. The multi-modal device was placed on top of a PMT (Hamamatsu Photonics, Shizuoka, Japan) in a light-excluding box.^{22 (link)} Voltage from the PMT was monitored for ATP quantification. ATP (Sigma-Aldrich, St Louis, MO) and norepinephrine (Sigma-Aldrich, St Louis, MO) standards were made in PBS the day of use. Traces shown in Figure 4C were smoothed in PeakFit (San Jose, CA) with a small Savitzky-Golay filter (0.5% window) for presentation purposes (to help filter noise).