Effect of nickel sulphate hexahydrate addition on crystal growth, structural, optical and biological applications of glycine single crystals

ABSTRACT

In the present study, single crystals of α- and γ-glycine have been successfully grown in the presence of nickel sulphate hexahydrate as an additive for the first time by using slow solvent evaporation method. The analytical grade chemicals of glycine and nickel sulphate hexahydrate were taken in five different molar ratios: 1:0.2, 1:0.4, 1:0.6, 1:0.8 and 1:1 respectively to find out the α, and γ-polymorph of glycine. The lower molar proportion of nickel sulphate hexahydrate yield only α-polymorph whereas the higher molar proportion of nickel sulphate hexahydrate yields only γ-polymorph of glycine which was confirmed by powder XRD studies. UV–Visible–NIR transmittance spectra were recorded for the samples to analyze the transparency in visible and near infrared region (NIR). The optical band gap Eg was estimated for grown nickel sulphate hexahydrate (NSH) added glycine crystals using UV–Visible–Transmission study. Functional groups present in the sample were identified by FTIR spectroscopic analysis. The in vitro antimicrobial activities of the synthesized nickel sulphate added glycine single crystals were investigated against gram positive, gram negative bacterial strains using the agar disk diffusion method.

KEYWORDS:

• Antibacterial activity
• glycine
• x-ray diffraction
• zone of inhibition

Additional information

Funding

One of the authors Dr. P. Dhanasekaran acknowledges the Department of Science and Technology - Science and Engineering Research Board (DST-SERB), Government of India for providing financial support for this work through a project sanctioned no. ECR/2016/000521 dated 18-Oct-2016.