Biosynthesis and characterization of CdS quantum dots in genetically engineered Escherichia coli

Abstract

Quantum dots (QDs) were prepared in genetically engineered Escherichia coli (E. coli) through the introduction of foreign genes encoding a CdS binding peptide. The CdS QDs were successfully separated from the bacteria through two methods, lysis and freezing–thawing of cells, and purified with an anion-exchange resin. High-resolution transmission electron microscopy, X-ray diffraction, luminescence spectroscopy, and energy dispersive X-ray spectroscopy were applied to characterize the as-prepared CdS QDs. The effects of reactant concentrations, bacteria incubation times, and reaction times on QD growth were systematically investigated. Our work demonstrates that genetically engineered bacteria can be used to synthesize QDs. The biologically synthesized QDs are expected to be more biocompatible probes in bio-labeling and imaging.

Biosynthesis and characterization of cadmium sulfide nanoparticles – An emphasis of zeta potential behavior due to capping

“…The determined bacterial protein is responsible for the same. Mi et al also showed that by genetically engineering the genes responsible for CdS binding peptide, CdS quantum dots could be synthesized [25]. The microorganisms and biomolecules provide a large number of nucleation centers to direct shape and crystallinity of developing inorganic nanomaterial and establish conditions for obtaining highly stable and dispersed nanoparticle systems [21].…”

Recent achievements in the microbial synthesis of semiconductor metal sulfide nanoparticles

“…In other studies, CdS QDs were prepared by using E. coli engineered by introducing foreign genes encoding a sulfide binding peptide [11] and by reacting Cd 2+ with C-phycoerythrin pigments extracted from the marine cyanobacterium, Phormidium tenue [6].…”

“…In addition, the chemically fabricated nanoparticles are less biocompatible, and their applications in biological and medical systems are restricted [7,9]. An appropriate alternative is the application of biological templates including carbohydrate, peptides, nucleotides, and fusion proteins [11]. The biological techniques can also be extended to living organisms such as bacteria, fungi, or yeasts which produce NPs through physiological and metabolic activities and by passive surface reactions on cell walls or extracellular structures [3,[11][12][13][14].…”

“…An appropriate alternative is the application of biological templates including carbohydrate, peptides, nucleotides, and fusion proteins [11]. The biological techniques can also be extended to living organisms such as bacteria, fungi, or yeasts which produce NPs through physiological and metabolic activities and by passive surface reactions on cell walls or extracellular structures [3,[11][12][13][14]. They are also more acceptable in terms of being ecofriendly, and not energy intensive, and producing biocompatible particles [3]; however, presents several challenges such as low production rate and quantity, lack of control over size and shape, process scale-up, and interpretation of the production mechanism [15,16].…”

Materials for FRET Analysis: Beyond Traditional Dye–Dye Combinations

“…There are reviews and detailed monographs describing QDs synthesis using various materials, generally involving wet chemistry techniques such as high-temperature organometallic synthesis, microwave or gamma irradiation, and aqueous colloidal and sol-gel methods [515,523,537,538]. Various biotemplated fabrication approaches have also been proposed for QD production, ranging from whole organism synthesis (bacteria, yeast, and viruses) to biomolecule-based ligands that facilitate nucleation and capping of the QDs during synthesis (nucleic acids and peptide sequences) [539][540][541][542][543]. While greener in terms of reagents and reaction conditions, these biofabrication methods tend to produce lower quality QDs, in terms of QY and size polydispersity, compared to high-temperature chemical synthetic techniques, but this may improve as our understanding of the underlying mechanisms that govern these syntheses grows [539][540][541][542][543].…”