Dmso d6

To prepare samples for ¹H-NMR measurements, pellets obtained from purification of the chiral particles were dried under vacuum for 1–2 h, then weighed and digested in deuterated dimethyl sulfoxide (DMSO-d₆; Cambridge Isotope Laboratories, 99.9% D). A 0.02 M stock solution of ferrocene (Thermo Scientific, 99%) in DMSO-d₆ was added to the digested pellet solution at 0.004 M, and was used to calibrate the intensity of the NMR spectra. NMR measurements were then collected using a Bruker Advance 400 MHz spectrometer. From the ferrocene-calibrated spectra, the total mass of ligands in solution could be calculated, and subtracted from the net pellet mass to yield the mass of CsPbBr₃. Assuming the particles to possess a cubical shape, the total number of QDs in the sample and hence total surface area could be calculated from the known volume and mass of the unit cell of orthorhombic CsPbBr₃. Combining the mass of ligand determined from the NMR measurements with this surface area allows the density of both chiral and achiral ligands to be estimated.

The reagents and the fatty acid–amino acid/peptide conjugates were analyzed using an LC-MS/MS system consisting of an Agilent 1100 LC system (HPLC-DAD-autosampler, Agilent Technologies, Santa Clara, CA, USA) and a QTRAP 6500⁺ quadruple-linear trap mass spectrophotometer with electrospray ionization (AB Sciex LLC, Framingham, MA, USA). The nuclear magnetic resonance (NMR) analysis was conducted using a Bruker 400 MHz NMR instrument, DMSO-d₆ (CAS No. 2206-27-1, 99.9 atom% D, Thermo-scientific, Fair Lawn, NJ, USA) as a solvent, and Topspin 4.3.0 version software. The ¹H NMR (400 MHz), ¹³C NMR (100 MHz), and ¹³C DEPT data were acquired using a purified compound (30 mg) dissolved in 0.7 mL of DMSO-d₆ in a 5 mm diameter NMR tube. DEPT 135 was used to determine the multiplicity of carbon atoms, and CH₂ groups showed inverted signals, whereas CH and CH₃ groups were upright. The quaternary carbon (C) did not show any signal.

PSI was extracted from organic baby spinach purchased at a local grocery store. Triton X-100 surfactant and 99% p-anisidine (4-methoxyaniline) were purchased from Millipore-Sigma. Silicon (100) wafers were purchased from WRS materials. Chromium-coated tungsten rods were purchased from R.D. Mathis. Gold shot (99.99% purity) was obtained from J&J Materials. Spectra/Por dialysis membrane tubing (6000 to 8000 Da MWCO) was obtained from Repligen. DMSO-d₆ (99.5%) was purchased from Thermo Fisher Scientific.