Calcium chloride dihydrate

Human iPS cell line 201B7 was provided by the RIKEN BRC through the National BioResource Project of the MEXT/AMED, Japan. The cell line was grown and maintained by culturing with feeder cells (SL10, Reprocell Inc.) at 37 °C in 5% CO₂ in a humidified atmosphere, using Primate ES cell medium (Reprocell Inc.), supplemented with bFGF (Fujifilm Wako Pure Chemical Corporation).
The cells were sub-cultured, when the cells are 80% confluent, using a cell scraper (AGC Techno Glass Co., Ltd) after processing by DPBS(−) (no calcium, no magnesium, Thermo Fisher Scientific Inc.) and CTK solution. CTK solution (0.25% trypsin + 1 mg/mL collagenase IV + 1 mM CaCl₂ + 20% KSR in DPBS (−)) was prepared with trypsin ((2.5%), no phenol red, Thermo Fisher Scientific Inc.), collagenase (type IV, powder, Thermo Fisher Scientific Inc.), calcium chloride dihydrate (Fujifilm Wako Pure Chemical Corporation), Knock Out^TM Serum Replacement (KSR, Thermo Fisher Scientific Inc.).

Sodium chloride (purity 99.5%), calcium chloride dihydrate (purity 99.9%), and sodium oxalate (purity 99.5%) were procured from Fujifilm Wako Pure Chemicals Co. All reagents were used without further purification. Deionized water, with a resistivity of 18.2 MΩ∙cm, was prepared by Urupure (Komatsu Electronics Corporation) and employed in the experiments. COD stones were sourced from patient samples (Supplementary Fig. 2a). This stone spontaneously passed through in the urine of a male patient (Sample1; 60-years old with a history of kidney stone disease). Ethical protocols were strictly followed in the handling of the samples for the experiment.

Lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, and glutaraldehyde were purchased from Tokyo Chemical Industry Co. Ltd. (Tokyo, Japan). Caprylic acid, capric acid, linoleic acid, SLS, sodium chloride (NaCl), disodium hydrogen phosphate 12-water (Na₂HPO₄•12H₂O), potassium dihydrogen phosphate (KH₂PO₄), sodium chloride (KCl), potassium hydroxide (KOH), hydrochloric acid (HCl), manganese (II) chloride tetrahydrate (MnCl₂•4H₂O), magnesium sulfate heptahydrate (MgSO₄•7H₂O), iron (II) sulfate heptahydrate (FeSO₄•7H₂O), calcium chloride dihydrate (CaCl₂•2H₂O), agar, crystal violet, Hank’s balanced salt solution (HBSS)(+) and 99.5% ethanol (EtOH) were purchased from FUJIFILM Wako Pure Chemical Corporation (Osaka, Japan). SLES was purchased from the NOF Corporation (Tokyo, Japan). The Dulbecco’s phosphate-buffered saline (d-PBS)(+) preparation reagent (with Ca and Mg) (100×) and fetal bovine serum (FBS) were purchased from Nacalai Tesque (Kyoto, Japan) and Thermo Fisher Scientific K.K. (Tokyo, Japan), respectively. WELPAS^® antiseptic solution for hands (0.2%), an alcohol-based disinfectant, was purchased from Maruishi Pharmaceutical Co. Ltd. (Osaka, Japan).