# Biomimetic Growth of Calcium Oxalate Hydrates: Shape Development and Structures in Agar Gel Matrices

## TL;DR

This paper studies how calcium oxalate crystals grow in agar gels, mimicking kidney stone formation and showing how pH affects crystal types.

## Contribution

The study introduces a biomimetic method using agar gel to grow calcium oxalate hydrates, revealing pH-dependent crystal morphologies similar to kidney stones.

## Key findings

- Calcium oxalate monohydrate (COM) forms platy crystallites, dumbbells, and spherulites in agar gels.
- Higher pH promotes calcium oxalate dihydrate (COD) growth while suppressing COM formation.
- The agar gel method mimics biomineralization processes seen in kidney stone development.

## Abstract

Crystal growth of calcium oxalate hydrates (COM: calcium oxalate monohydrate; COD: ‐dihydrate; COT: ‐trihydrate) is a specific example of pathological biomineralization due to their harmful role as kidney/urinary stones. In this work, the biomimetic growth of calcium oxalate hydrates has been achieved using double diffusion technique in agar gel matrix. In vitro experimental models for the growth of calcium oxalates can give valuable information on the formation of biominerals of kidney/urinary stones. Diverse morphological forms of COM are grown in agar gel matrices ranging from platy crystallites to dumbbells and spherulites. The morphology of COM grown in agar gel resembles COM biominerals remarkably. Furthermore, it has been discovered that a higher pH of the agar gel promotes COD development while suppressing COM growth.

The biomimetic growth of calcium oxalate hydrates is conducted using a double diffusion technique in agar gel. The results reveal the shape development of calcium oxalate monohydrate (COM) and dihydrate (COD), resembling biominerals of kidney stones. The pH variations influence phase selection, with COM forming at lower pH and COD at higher pH. The findings offer insights into pathological biomineralization and urolithiasis.