Hello, we use the same procedure as the kits or we make our own solutions.

We usually use Picric acid 18 mmol/L and Sodium hydroxide 0.30 mol/L. We use a 96-well plate, both the calibration curve and samples are made in duplicate. We dilute the urine 1:10

The creatinine standard is 2 mg/dL

Good luck.

Juan Manuel Gallardo Thank you for your answer.

Do you use picric acid and NaOH in a 1:1 ratio?

And what is the ratio of standard sample used with respect to picric acid and NaOH ratio?

1. Yes

Procedure

in 96 well plates

1]. 5 uL sample 2]. 45 uL DW 3]. 50 uL pícric acid 4]. 50 uL NaOH 5]. orbital shaker very slow 6]. 22 oC, 3 min. 7]. Read 540 nm (or 492, 500, and 510 nm) in microplate reader. 8]. read in the first 30 min, no more

Calibration curve Creatinina (1 ug/uL): 0, 2, 4, 8, 15, 30, and 50 uL DW: 50, 48, 46, 42, 35, 20, and 0 uL Picric acid : 50 uL / well NaOH: 50 uL /well Sample volumen: 5, 10, o 15 uL

Good luck

Thank you Juan