Hybrid gold single crystals incorporating amino acids

TL;DR

This study demonstrates the first incorporation of amino acids into gold single crystals, revealing a new method for creating hybrid organic-metal composites with potential applications in sensing and biomedicine.

Contribution

The paper reports the novel incorporation of amino acids into gold crystal lattices, a first in the field, using a versatile fabrication strategy.

Findings

Amino acids can be incorporated into gold crystals with varying concentrations.

Cysteine shows the highest incorporation among tested amino acids.

The incorporation affects crystal shape and structure, indicating complex interactions.

Abstract

Composite hybrid gold crystals are of profound interest in various research areas ranging from materials science to biology. Their importance is due to their unique properties and potential implementation, for example in sensing or in bio-nanomedicine. Here we report on the formation of hybrid organic-metal composites via the incorporation of selected amino acids histidine, aspartic acid, serine, glutamine, alanine, cysteine, and selenocystine into the crystal lattice of single crystals of gold. We used electron microscopy, chemical analysis and high-resolution synchrotron powder X ray diffraction to examine these composites. Crystal shape, as well as atomic concentrations of occluded amino acids and their impact on the crystal structure of gold, were determined. Concentration of the incorporated amino acid was highest for cysteine, followed by serine and aspartic acid. Our results indicate that the incorporation process probably occurs through a complex interaction of their individual functional groups with gold atoms. Although various organic gold composites have been prepared, to the best of our knowledge this is the first reported finding of incorporation of organic molecules within the gold lattice. We present a versatile strategy for fabricating crystalline nanohybrid composite gold crystals of potential importance for a wide range of applications.