Bill of Materials
Reagents
| Item | Use | Supplier | Qty | Est. Cost | Notes |
|---|---|---|---|---|---|
| Iron(III) nitrate nonahydrate 98% | Trinder reagent (salicylate) | Strem (93-2614) | 250g | ~$31 | Makes ~625 batches of working solution |
| Sodium salicylate 99% | Salicylate calibration standard | Amazon | 100g | ~$20 | CAS 54-21-7 |
| Muriatic acid (HCl ~31%) | Trinder reagent, pH adjustment | Hardware store | 1 gallon | ~$10 | Pool supply aisle |
| NaOH (sodium hydroxide) | Extraction, pH adjustment | Hardware store | 500g | ~$5-10 | Drain cleaner or food grade |
| Copper sulfate pentahydrate | Oxalate working reagent | Aquarium/garden supply | 100g | ~$10 | CAS 7758-99-8 |
| Reactive Blue 4 (35% dye content) | Oxalate indicator dye | Chem-Impex | 25g | ~$50-80 | CAS 13324-20-4. Note: Calpachem restricts residential shipping — try Chem-Impex instead |
| Sodium oxalate | Oxalate calibration standard | Lab supplier | 100g | ~$15-25 | CAS 62-76-0 |
| Chloroauric acid (HAuCl₄) | AuNP synthesis for amine screen | Sigma/Strem | 1g | ~$20-40 | Handle carefully — irritant |
| Sodium citrate | AuNP synthesis | Lab supplier / grocery | 100g | ~$5-10 | Trisodium citrate dihydrate |
| Distilled water | All assays | Grocery store | 1 gallon | ~$1-2 |
Reagent total estimate: ~$130-180 upfront
Consumables Per Test
| Item | Source | Cost |
|---|---|---|
| Plastic cuvettes | Amazon (100 pack) | ~$0.10 each |
| Coffee filters | On hand | ~$0.01 |
| Plastic tubes/vials | Amazon | ~$0.05 each |
| Histamine enzyme strips (if triggered) | BioAssay Systems QQHIST10 | ~$8 each |
Cost per salicylate+oxalate test: ~8.50
Hardware
See Colorimeter Build for full hardware BOM.
| Item | Source | Est. Cost |
|---|---|---|
| AS7265x Triad Spectroscopy Sensor | SparkFun DEV-15050 | ~$65 |
| Arduino Nano or ESP32 | Amazon | $5-15 |
| Plastic cuvettes 100-pack | Amazon | ~$10 |
| 3D print filament (black PLA/PETG) | On hand | ~$3 |
| Misc electronics | On hand | ~$5 |
Hardware total: ~$85-100 (one-time)
Sourcing Notes
Residential Address Restrictions
- Reactive Blue 4 from Calpachem explicitly excludes residential delivery
- Chem-Impex appears to be more accessible — verify before ordering
- Alternative: contact a local makerspace, university chemistry department, or community lab as receiving address
Shipping Considerations
- HCl and NaOH are regulated for shipping — buy locally from hardware store
- Chloroauric acid may require hazmat shipping — factor into cost
- Iron nitrate is an oxidizer — store away from combustibles
Suppliers
| Supplier | Good For |
|---|---|
| Strem Chemicals (strem.com) | Iron nitrate, other inorganics |
| Chem-Impex (chemimpex.com) | Reactive Blue 4, misc chemicals |
| Amazon | Sodium salicylate, copper sulfate, consumables |
| SparkFun (sparkfun.com) | AS7265x sensor |
| BioAssay Systems (bioassaysys.com) | Histamine enzyme strips |
| Hardware store | HCl (muriatic acid), NaOH (drain cleaner) |
| Aquarium/garden store | Copper sulfate |