Poloxamer 188 f68

Dibucaine, poloxamer 188 (F68), and 5-doxyl-stearic acid spin labels (5-SASL) were obtained from Sigma-Aldrich (St Louis, MO, USA). Myristyl myristate (MM) and cetyl palmitate (CP) were from Dhaymers Fine Chemicals (São Paulo, Brazil) and Croda (São Paulo, Brazil), respectively. Other reagents used were HPLC grade: acetonitrile (J.T. Baker, Goias, Brazil), triethylamine (Vetec Rio de Janeiro, Brazil), and orthophosphoric acid (Cetus Ind. Com. Prod. Quim., Santo Amaro, Brazil). Deionized water (18.2 mΩ cm) was obtained from a Waters ultrapure water system (Merck KGaA, Darmstadt, Germany).

Triptolide (TP, purity >99%), PLGA (with a copolymer ratio of lactide : glycolide 50 : 50 and Mw : 40-75 kDa), poloxamer 188 (F-68, Mw : 8350 Da), amyloid beta-peptide_1-42 (Aβ_1-42), and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) were supplied by Sigma-Aldrich Co. Ltd. (Gillingham, UK). Dichlorodihydrofluorescein diacetate (DCFH-DA), fluo-3 acetoxymethyl ester (fluo-3-AM), LysoTracker Red, and 4′,6-diamidino-2-phenylindole (DAPI) were from Molecular Probes (Eugene, OR, USA). Fetal bovine serum (FBS), horse serum (HS), nerve growth factor (NGF), penicillin, and streptomycin were provided by GIBCO, Invitrogen Corporation (Carlsbad, CA, USA). Chitosan hydrochloride (degree of deacetylation, 80% ~90%, viscosity, 30 mPa.s) was obtained from Shanghai KABO Trading Company (Shanghai, China). Polyethylene Glycol (PEG, MW = 20 kDa), borneol, mentholum, and Tween-80 were purchased from Chengdu Kelong Chemical Company (Chengdu, China). The other chemicals were of analytical reagent grade.