amide resin (200–400 mesh, loading = 0.345 mmol/g), Fmoc-Gly-OH,
Fmoc-Pro-OH, Fmoc-Hyp(tBu)-OH, Fmoc-Asp(Otbu)-OH, Fmoc-Tyr(tBu)-OH,
Fmoc-Ala-OH, Fmoc-Phe-OH, O-Benzotriazole-N,N,N′,N′-tetramethyl-uronium-hexafluorophosphate (HBTU),
and N-hydroxybenzotriazole (HOBt, anhydrous) were
purchased from GL Biochemical Company (Shanghai, China). N,N-Diisopropylethylamine (DIEA) was obtained from
Hanhong Chemical Technology Co. Ltd (Shanghai, China). 5(6)-Carboxylfluorescein
(FAM) and piperazine (anhydrous) were provided by Aladdin Industrial
Corporation (Shanghai, China). Trifluoroacetic acid (TFA) and triisopropylsilane
(Tis) were purchased from Tokyo Chemical Industry Co. Ltd (Tokyo,
Japan). Bovine serum albumin (BSA), goat serum, and 4′,6-diamidino-2-phenylindole
(DAPI) were obtained from Solarbio Science & Technology Co. Ltd
(Beijing, China). Hemoglobin, trypsin, and pepsin were obtained from
Yuanye Biological Technology Co. Ltd (Shanghai, China). Gelatin was
obtained from Biotop Science & Technology Co. Ltd (Beijing, China).
All of the commercial reagents were of analytical grade and were used
without further purification.