The Researchers’ Success in Laboratory Building of Nanoparticles of Calcium Hydroxide

Having built laboratory nanoparticles of calcium hydroxide, researchers of Mashhad University of Medical Sciences studied their performance in reinforcing artistic and historical monuments.

Calcium hydroxide nanoparticles increase the speed of the process of historical monuments’ restoration in a green and low-cost way.

Some artistic and historical monuments have been damaged over time through exposure to air pollution and different climatic conditions. Fragility of these monuments is in such a way that causes problems for the restoration of monuments during the acid removal and reinforcement process. Therefore, it is of great significance to design methods and compounds with no long-term harmful effects on historic monuments that can accelerate the restoration process.

Majid Daroudi, the project researcher, stated that this study is aimed at attempting to introduce a green method for use in the acid removal and reinforcement process of historical and artistic paper monuments.

He stated that historical and artistic monuments become quite fragile against acid hydrolysis and oxidation processes caused by climatic conditions. In this study, we attempted to perform three restoration operations, acid removal, ant oxidation, and reinforcement in one stage using calcium hydroxide nanoparticles so that these operations accelerate the reduction of the restoration time and do not have any harmful effects on historical monuments in the long-term.

These researchers added that using calcium hydroxide nanoparticles makes spraying these substances during the restoration operation feasible. Spraying the nanoparticles leads to lack of mineral density as well as blemish and wrinkle formation on the restoration paper due to the tiny size of nanoparticles.

Droudi stated that the increasing depth of penetration caused by nanoparticle absorption capability by the paper fibers increases the efficiency of nanoparticles compared to larger particles.

Pointing out different stages of nanoparticles’ construction and studying their performance, he stated that after the synthesis of calcium hydroxide nanoparticles by the sol-gel method, the synthetic nanoparticles were characterized using different methods including X-ray analysis (XRD) and scanning electron microscopy (FESEM).

This researcher emphasized that considering the medical applications of these nanoparticles, the cytotoxicity of calcium hydroxide nanoparticles for various applications was studied.

According to Droudi, The results showed that these nanoparticles are non-toxic in concentrations less than 30 micrograms per milliliter. Then, the effect of these nanoparticles in various restoration operations was investigated.

This project was conducted in collaboration with Majid Droudi, Faculty Member of Mashhad University of Medical Sciences, Mahmoud Ebrahimi, Faculty Member of Islamic Azad University of Mashhad, and Maryam Bagherpour, master of libraries and museums of Astan Quds Razavi.

The results of this study were published in the Journal of Ceramics International (Volume 42, Number 3, 2016, pages 3816-3819).