Prebiotic-chemistry inspired polymer coatings for biomedical and material science applications

Abstract

In the field of prebiotic chemistry, hydrogen cyanide (HCN)-derived polymers have been studied for many years as a possible source of the precursors that provide the building blocks for proteins as well as nucleic acids, and they have also been associated with the origin of life. The HCN trimer, aminomalononitrile (AMN), polymerizes to give a brown complex nitrogenous polymer. We report the one-step polymerization-deposition of AMN as a simple generic surface-coating method and as an application of prebiotic chemical research to material science. We found that this polymerization, carried out in buffered aqueous solutions, can be used to coat a wide range of organic and inorganic substrate materials. The robust, non-cytotoxic coatings also provide for excellent cell attachment, suggesting potential biomedical applications. Furthermore, the coating chemistry allows for the immobilization of other compounds, including metals, both during coating formation or by performing secondary immobilization reactions.

A Comparative Study on HCN Polymers Synthesized by Polymerization of NH4CN or Diaminomaleonitrile in Aqueous Media: New Perspectives for Prebiotic Chemistry and Materials Science

“…However, DAMN polymers could be obtained simply by heating aqueous suspensions at 80 °C with high conversions for different theoretical initial concentrations and several reaction times (Table ). It is noteworthy that this temperature is lower than that previously reported, that is, a moderate temperature can also lead to DAMN polymerization. The FTIR spectra of these new insoluble DAMN polymers (Figure c and d) resembled those of the NH 4 CN polymers synthesized at low temperatures ( T ≤38 °C), as well as those of analogous NH 4 CN polymers prepared at 80 °C (Figures a and b) and other FTIR spectra of HCN polymers obtained under different experimental conditions in aqueous solutions and aprotic media, or even without solvents .…”

“…As shown in Scheme , HCN and its sodium or potassium salts polymerize in aqueous medium in a broad range of temperatures at alkaline pH (preferentially pH 8–10) in a spontaneous process (e.g., see ref. ) Furthermore, the trimer of HCN, aminomalononitrile (AMN), polymerizes spontaneously in aqueous solution at pH 8.5 (Scheme ) . However, although DAMN is believed to be one of the main intermediates in the polymerization of HCN, the only aqueous polymerization of DAMN described previously was achieved by heating aqueous suspensions at 100 °C (Scheme ) .…”

“…) Furthermore, the trimer of HCN, aminomalononitrile (AMN), polymerizes spontaneously in aqueous solution at pH 8.5 (Scheme ) . However, although DAMN is believed to be one of the main intermediates in the polymerization of HCN, the only aqueous polymerization of DAMN described previously was achieved by heating aqueous suspensions at 100 °C (Scheme ) . Hence, suspensions of DAMN in doubly distilled (dd) water were left to stand at room temperature for one month to 1) assess the spontaneity of the process, 2) explore the synthetic conditions for the production of HCN polymers from DAMN and 3) understand the role of DAMN in the pathway of cyanide polymerization (note that most of the water‐based polymerization reactions of HCN were carried out at alkaline pH).…”

“…The polymerization conditions for the synthesis of HCN polymers systematicallys tudied in the present work are shown in Ta ble 1. From here on, the HCN polymers synthesized by using NH 4 CN as reactant are referred to as NH 4 CN polymers ( Table 1, entries 1-11) and, analogously,t hose obtained from DAMN are denoted DAMN polymers ( Table 1, entries [12][13][14][15][16][17][18][19][20][21][22].T he reaction temperature of 80 8Cw as chosen on the basis of previous results for NH 4 CN polymers in which maximum limiting conversions were obtained and an autocatalytic model could be applied to explain the kinetics of polymerization of NH 4 CN. [18,24] The spontaneous polymerization of DAMN was explored in this work for the first time for comparison with the polymerization process thermally induceda t8 0 8C.…”

“…Diaminomaleonitrile (DAMN), the formal tetramer of HCN, has been suggested to be the main intermediate in the production of HCN polymers . However, only two syntheses of HCN polymers from DAMN as starting reactant have been reported, and only one of them is an aqueous‐based process (Scheme ). To explore this synthetic route, several HCN polymers were synthesized from DAMN by routes analogous to those using NH 4 CN as the reactant (Table ) and studied by the same multitechnique methodology.…”