A Surface Mediated Supramolecular Chiral Phenomenon for Recognition of l- and d-Cysteine

Abstract

Chiral recognition is of fundamental importance in chemistry and life sciences and the principle of chiral recognition is instructive in chiral separation and enantioselective catalysis. Non-chiral Ag nanoparticles (NPs) conjugated with chiral cysteine (Cys) molecules demonstrate strong circular dichroism (CD) responses in the UV range. The optical activities of the l-/d-Cys capped Ag NPs are associated with the formation of order arrangements of chiral molecules on the surface of Ag NPs, which are promoted by the electrostatic attraction and hydrogen bonding interaction. The intensity of the chiroptical response is related to the total surface area of Ag NPs in the colloidal solution. The anisotropy factor on the order of 10−2 is acquired for Ag NPs with the size varying from ~2.4 to ~4.5 nm. We demonstrate a simple and effective method for the fabrication of a quantitative chiral sensing platform, in which mesoporous silica coated Ag nanoparticles (Ag@mSiO2) were used as chiral probes for recognition and quantification of Cys enantiomers.

Chirality Transfer from Sub‐Nanometer Biochemical Molecules to Sub‐Micrometer Plasmonic Metastructures: Physiochemical Mechanisms, Biosensing, and Bioimaging Opportunities

“…With the help of mesoporous silica coated Ag NPs (Ag@mSiO 2 ), Wang et al reported the discrimination of enantiomeric cysteine molecules ( l ‐ and d ‐) by monitoring the new mirror‐like CD bands appeared in the range of 240–350 nm. [ 205 ] Importantly, the formation of cysteine‐Ag@mSiO 2 supramolecular networks by electrostatic attraction and hydrogen bonding enables a LOD as low as 12.5 × 10 −6 m , which surpasses conventional electronic CD measurement techniques considerably.…”

Advances in Transition‐Metal‐Based Dual‐Atom Oxygen Electrocatalysts

“…[ 148 ] Researchers have found that the DACs formed by the combination of transition metals has excellent performance as a cathode catalyst for Zn–air batteries. [ 122,149,150 ] Metal–air batteries are generally composed of metal negative electrode, air positive electrodes, separators, and appropriate electrolytes ( Figure ).…”

Classical nexus between chiral inducers and achiral silver nanoparticles and integration of the digital XOR logic gate

“…Chiral modification by L/D-cysteine 200 mL of L-and D-cysteine chiral ligand with different concentrations (0.1, 0.5, 1, 5, 10 mM) were dropped into 2 mL Ag NPs colloidal solution and 1.8 mL of distilled water in a 15 mL vial; 40 the reaction was stirred at 450 rpm at room temperature for 6 h, maintaining the pH between 3 and 4. The obtained Lcysteine-capped Ag NPs (L-Cys@Ag) and D-cysteine-capped AgNPs (D-Cys@Ag) were stored at 4 1C for further studies.…”

“…39 Recently, few groups have employed different synthesis platforms (Turkevich method, microwaveassisted, ultrasonication) to prepare either L or D or L-and Dcysteine-modified Ag NPs for studying chiroptical properties, chiral amino acids, and biological fluids sensing. [40][41][42][43] However, the electrical properties of chiral assemblies are almost untouched, and chiral-induced growth is uncontrolled. Thus, there is a pressing need for using them as circuit elements in electronic devices and understanding the current-voltage relationship as it is vital for real applications, besides achieving controlled growth via a feasible chemical method.…”