Gc ultra grade

Tetrachloroauric(III) acid trihydrate (HAuCl₄·3H₂O) was synthesized according to Schubert et al.,²⁷ oleylamine (Acros Organics, C18 content of about 80–90%) was purchased from Fisher Scientific GmbH (Schwerte, Germany) and filtered with a 0.45 μm Rotilabo-PTFE syringe filter from Carl Roth GmbH + Co. KG (Karlsruhe, Germany) prior to each usage to remove any oxidized residues, triisopropylsilane (95%) and n-hexane (at least 99% p.a.) were obtained from abcr GmbH (Karlsruhe, Germany), pentane (Sigma Aldrich, for HPLC, ≥99%) and borane tert-butylamine complex (Sigma Aldrich, 97%) were obtained from Merck KGaA (Darmstadt, Germany), cyclohexane (ROTISOLV ≥ 99.9%, GC Ultra Grade) was bought from Carl Roth GmbH + Co. KG (Karlsruhe, Germany) and absolute ethanol (99.8%, analytical reagent grade) was procured from Fisher Scientific GmbH (Schwerte, Germany). All chemicals were used without further purification unless explicitly mentioned.

To prepare the MP and NP, the following compounds were used: AMCA (~90%, Sigma-Aldrich, Steinheim, Germany); N-ethyl-N′-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) (≥95%, Sigma-Aldrich); acetonitrile (≥99.5%, pharmaceutical quality, Sigma-Aldrich); ethanol (≥95%, Rotipuran, Carl Roth GmbH, Karlsruhe, Germany); acetone (ROTISOLV^® ≥99.9%, GC Ultra Grade, Carl Roth GmbH); PLGA 50:50 (RESOMER^® RG 502H, MW 7,000–17,000 g/mol, pharmaceutical quality, kindly provided by Boehringer Ingelheim, Ingelheim am Rhein, Germany); poly(ethylene glycol)-block-PLGA (PEG-PLGA) 50:50 (RESOMER^® RGP d 50155, 5 kDa PEG, pharmaceutical quality, Evonik, Essen, Germany); polyvinyl alcohol (Mowiol 4–88, 31,000 g/mol, Kuraray Specialities Europe, Frankfurt, Germany); ultrapure chitosan chloride (30–400 kDa, pharmaceutical quality, Heppe Medical Chitosan, Halle, Germany); and ethyl acetate (≥99.5%, p.a., ISO, Carl Roth GmbH).