Table 1.
Cost, formation timeline and uniformity of matrix-independent and matrix-dependent techniques.
| Technique | Cost | Days to Form | Diameter + Std. Dev |
|---|---|---|---|
| Liquid Overlay Technique (LOT) | $62/24-well plate (Aggrewell™, StemCell™ Technologies, Vancouver, BC, Canada) | 24 h (OVCAR8) [12] 24 h (RT4) [27] |
274.08 ± 13.98 μm to 492.14 ± 25.32 μm [27] |
| Hanging Drop | _____ | 24 h (RT4) [27] 12–24 h (MCF-7) [28] |
340.92 ± 16.98 to 563.97 ± 28.53 μm (RT4) [27] 205 ± 20 µm (MCF-7) [28] |
| Collagen | $222/100 mg (Rat tail collagen type I, Sigma Aldrich, St. Louis, MO, USA) | Day 3 (A2780) [29] | 211.75 μm ± 16 μm (A2780) [29] |
| Hyaluronic Acid | $175/g (<10 kDa to >1.8 MDa Sodium Hyaluronate, LifeCore Biomedical, Chaska, MN, USA) | Day 4 (LNCaP) [30] | _____ |
| Matrigel® | $314.62/10 mL (Corning®, Corning, NY, USA) | Day 3 (MDA-MB-231) [31] Day 7 (LNCaP) [32] |
120.2 μm ± 3.8 μm (LNCaP) [32] |
| Alginate | $127/kg (Sodium Alginate, Sigma Aldrich) | Day 7 (U-251) [33] | 99 ± 18.9 μm (MCF-7) [34] |
| Chitosan | $68.60/50 g (medium MW, Sigma Aldrich) | Day 3 (U87 and U118) [35] Day 7 (MCF-7) [36] |
_____ |
| Poly(ethylene glycol) (PEG) | $50–250/kg (Sigma Aldrich) | Day 3 (MCF-7) [37] Day 7 (LNCaP) [38] (OV-MZ6, SKOV3) [39] | _____ |
| Peptide-based | $333 (PuraMatrix™ RADA16-I, Corning®) | Day 7 (LNCaP, RADA16-I, bQ13, Q11) [32] Day 5 (MDA-MB-435S) [40] |
112.2 ± 5.0 μm in bQ13 (LNCaP) [32] 114.6 ± 5.5 μm in RADA16-I (LNCaP) [32] 111.6 ± 4.7 μm in Q11 (LNCaP) [32] |