UV-Induced Nanoparticles-Formation, Properties and Their Potential Role in Origin of Life.

Lukas Nejdl,Martin Ferus,Vojtech Adam,Martina Matouskova,Martina Havlikova,Marketa Vaculovicova,David Hynek,Jakub Kapus,Kristyna Zemankova,Michaela Buresova,Kledi Xhaxhiu,Filip Mravec

doi:10.3390/nano10081529

Abstract

Inorganic nanoparticles might have played a vital role in the transition from inorganic chemistry to self-sustaining living systems. Such transition may have been triggered or controlled by processes requiring not only versatile catalysts but also suitable reaction surfaces. Here, experimental results showing that multicolor quantum dots might have been able to participate as catalysts in several specific and nonspecific reactions, relevant to the prebiotic chemistry are demonstrated. A very fast and easy UV-induced formation of ZnCd quantum dots (QDs) with a quantum yield of up to 47% was shown to occur 5 min after UV exposure of the solution containing Zn(II) and Cd(II) in the presence of a thiol capping agent. In addition to QDs formation, xanthine activity was observed in the solution. The role of solar radiation to induce ZnCd QDs formation was replicated during a stratospheric balloon flight.

Highlights

Nanozymes are modern, man-made alternatives to natural enzymes
The total amount of UV-B and UV-C radiation that reached the surface of early Earth in the Archean age might have been higher than nowadays, and further enhanced due to the lack of an ozone layer [31] which might have led to the formation of various types of metallic nanoparticles or nanoclusters ([2Fe–2S] and [4Fe–4S] [32]) with nanozymatic or redox activity
Principles involved in the behavior of these nanoclusters/nanoparticles might have evolved into metabolic-like networks preceding the emergence of the first living systems

Summary

Introduction

Man-made alternatives to natural enzymes. Their main advantages over the natural enzymes include stability, scalability, chemical diversity, and functionality in nonaqueous solvents [1]. The versatility of QDs consist in a wide range of application and in many approaches of aqueous syntheses assisted by microwaves [3], lasers [4], UV irradiation [5], electrochemistry [6,7], ultrasounds [8] or living organisms [9] (microorganisms, animals, plant extract, fungi and actinomycete) and all precursors of QDs like Zinc, Cadmium and Sulfur can be found in the same ore—Sphalerite or Wurtzite [10] This enormous versatility nominates them as suitable models relevant to the prebiotic chemistry. Numerous reactions might have been mediated, controlled and driven by nanoparticles and the synthesis of simple organic molecules with potential biological activity has started

Methods

Results

Conclusion