Back to Journals » International Journal of Nanomedicine » Volume 7

In vitro removal of toxic heavy metals by poly(γ-glutamic acid)-coated superparamagnetic nanoparticles

Authors Inbaraj BS, Chen BH

Received 30 May 2012

Accepted for publication 26 June 2012

Published 10 August 2012 Volume 2012:7 Pages 4419—4432

DOI https://doi.org/10.2147/IJN.S34396

Checked for plagiarism Yes

Review by Single-blind

Peer reviewer comments 3

Baskaran Stephen Inbaraj,1 Bing-Huei Chen1,2

1
Department of Food Science, 2Graduate Institute of Medicine, Fu Jen University, Taipei, Taiwan

Background: Chelation therapy involving organic chelators for treatment of heavy metal intoxication can cause cardiac arrest, kidney overload, mineral deficiency, and anemia.
Methods: In this study, superparamagnetic iron oxide nanoparticles (SPIONs) modified with an edible biopolymer poly(γ-glutamic acid) (PGA) were synthesized by coprecipitation method, characterized and evaluated for their removal efficiency of heavy metals from a metal solution, and simulated gastrointestinal fluid (SGIF).
Results: Instrumental characterization of bare- and PGA-SPIONs revealed 7% coating of PGA on SPIONs with a spherical shape and an iron oxide spinel structure belonging to magnetite. The particle sizes as determined from transmission electron microscopy images were 8.5 and 11.7 nm for bare- and PGA-SPIONs, respectively, while the magnetization values were 70.3 and 61.5 emu/g. Upon coating with PGA, the zeta potentials were shifted from positive to negative at most of the environmental pH (3–8) and biological pH (1–8), implying good dispersion in aqueous suspension and favorable conditions for heavy metal removal. Batch studies showed rapid removal of lead and cadmium with the kinetic rates estimated by pseudo-second-order model being 0.212 and 0.424 g/mg•min, respectively. A maximum removal occurred in the pH range 4–8 in deionized water and 5–8 in SGIF corresponding to most gastrointestinal pH except for the stomach. Addition of different ionic strengths (0.001–1 M sodium acetate) and essential metals (Cu, Fe, Zn, Mg, Ca, and K) did not show any marked influence on lead removal by PGA-SPIONs, but significantly reduced the binding of cadmium. Compared to deionized water, the lead removal from SGIF was high at all pH with the Langmuir monolayer removal capacity being 98.70 mg/g for the former and 147.71 mg/g for the latter. However, a lower cadmium removal capacity was shown for SGIF (23.15 mg/g) than for deionized water (31.13 mg/g).
Conclusion: These results suggest that PGA-SPIONs could be used as a metal chelator for clinical treatment of metal poisoning.

Keywords: superparamagnetic iron oxide nanoparticles, poly(γ-glutamic acid), heavy metals, chelation therapy, gastrointestinal pH, kinetics

Creative Commons License This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/terms.php and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.

Download Article [PDF]  View Full Text [HTML][Machine readable]

 

Readers of this article also read:

Magnetic removal of Entamoeba cysts from water using chitosan oligosaccharide-coated iron oxide nanoparticles

Shukla S, Arora V, Jadaun A, Kumar J, Singh N, Jain VK

International Journal of Nanomedicine 2015, 10:4901-4917

Published Date: 31 July 2015

A novel preparation method for silicone oil nanoemulsions and its application for coating hair with silicone

Hu Z, Liao M, Chen Y, Cai Y, Meng L, Liu Y, Lv N, Liu Z, Yuan W

International Journal of Nanomedicine 2012, 7:5719-5724

Published Date: 12 November 2012

Modification of palm kernel oil esters nanoemulsions with hydrocolloid gum for enhanced topical delivery of ibuprofen

Salim N, Basri M, Rahman MBA, Abdullah DK, Basri H

International Journal of Nanomedicine 2012, 7:4739-4747

Published Date: 7 September 2012

Preparation and evaluation of quercetin-loaded lecithin-chitosan nanoparticles for topical delivery

Tan Q, Liu WD, Guo CY, Zhai GX

International Journal of Nanomedicine 2011, 6:1621-1630

Published Date: 10 August 2011

Function of the dendritic setae in Aedes aegypti mosquito pupae: float hairs don't float

William S Romoser, Marco V Neira Oviedo

Open Access Insect Physiology 2011, 3:7-11

Published Date: 16 March 2011

Aqueous humor penetration of topical bimatoprost 0.01% and bimatoprost 0.03% in rabbits

Abayomi B Ogundele, Mark C Jasek

Clinical Ophthalmology 2010, 4:1447-1450

Published Date: 7 December 2010