Polysorbate 80

Conventional formulation of metribuzin (Sencor^® 480), technical metribuzin (95% purity), and ¹⁴C-metribuzin (98% purity and 2.3 Bq mg⁻¹ of specific activity, American Radiolabeled Chemicals, Inc., St. Louis, MO, USA) and Scintillation solution (Ultima Gold, PerkinElmer, Waltham, MA, USA) were used in the studies. In nanoparticle preparation, caprylic/capric triglyceride (Myritol 318) was purchased from Basf (Basf Co. Ltd., São Paulo, SP, Brazil), poly-ε-caprolactone (PCL) (Mn∼80,000 Da), polysorbate 80 (Mn∼1310 Da), and sorbitane monostearate (Mw = 430.63 g mol⁻¹) were purchased from Sigma Aldrich (Sigma-Aldrich, Chem. Co., St. Louis, MO, USA). Soil samples were collected in Paraná and São Paulo State and organic residues were collected in agricultural areas.

The immunoreactivity assay was conducted according to previous reported^{43 (link), 44 (link)}. Each well in ELISA plates (Corning Incorporated, USA) was coated with 5 μg/ml of recombinant human VEGF165 (R&D Systems) at 4 °C overnight, and then VEGF165 solution was adjusted to pH 9.6 by adding 15 mM Na₂CO₃ and 35 mM NaHCO₃. Thereafter, the wells were blocked with 100 μL 1% human serum albumin (HSA, Sigma) in 0.067 M PBS. After blocking, the wells were washed three times with 0.1% polysorbate 80 (Sigma) in 0.067 M PBS. For the following binding assay, 10 ng/ml of ^99mTc-MAG₃-bevacizumab was added to the wells with VEGF coated. All wells were allowed to incubate for 2 h at room temperature. Subsequently, unbound antibody was removed by washing the wells three times with 0.1% polysorbate 80 in 0.067 M PBS. Finally, the bound antibody was solubilized with 0.2 M NaOH and withdrawn for gamma counting. The percentage of binding was calculated as bound counts divided by total counts. Competition experiments were performed by adding an excess of unlabeled bevacizumab (1000 fold) to the wells one hour in advance before ^99mTc-MAG₃-bevacizumab was added into VEGF165 coated wells. Each group was conducted in triplicate.

Quercetin (3,3′,4′,5,6-Pentahydroxyflavone,2-(3,4-Dihydroxyphenyl)-3,5,7-trihydroxy-4H-1-benzopyran-4-one, QT) and polysorbate 80 (polyoxyethylenesorbitan monooleate, tween 80, T80), were purchased from Sigma-Aldrich (St. Louis, MO, USA). The soybean lecithin (PC) (90% phosphatidylcholine) was Epikuron 200 from Lucas Meyer (Hamburg, Germany). Nylon (New York, NY, USA), polytetrafluoroethylene (PTFE, Whatman^®, Maidstone, UK) (pore size 200 nm), and STRAT-M^® membranes were purchased from Sigma Aldrich (Milan, Italy). Solvents were of HPLC grade and all other chemicals were of analytical grade.

CP, triphenylphosphine, silver nitrate, monochloroacetic acid, PVP, and polysorbate 80 were obtained from Sigma Chemical Co. (St. Louis, MO, USA). Dichloromethane, absolute ethanol, methanol, glacial acetic acid, and WSP were from RCI Lab-scan Co., Ltd. (Bangkok, Thailand). CP-CG was from Ultradent Product Inc. (Salt Lake City, UT, USA). Rice seeds of Thai rice, variety Saohai, were obtained from the local market (Chiang Mai, Thailand). All other chemicals and solvents were of AR grade or the highest grade available.

Nanocurcumin was prepared according to methods described in our previous report (24 (link)). Briefly, 10 g of curcumin (Sigma, USA) was dissolved in 2.5 liters of distilled ethanol at room temperature and filtered to obtain a clear solution. This solution was then stirred in a high-speed homogenizer (T 25 digital Ultra-Turrax) at 12,000 to 15,000 rpm, and the required volume of Milli Q water containing 0.1% citric acid (Merck, India) was added to it slowly over a period of 1 h until the ethanol concentration reached 40% (vol/vol) and curcumin particles started to precipitate from the solution. The entire suspension was then homogenized over ice in a high-pressure homogenizer (Avestin C5 high-pressure homogenizer) at 30,000 lb/in² for 30 cycles. The aqueous suspension was then made to 0.1% polysorbate 80 (Sigma, USA), homogenized at 12,000 to 15,000 rpm (T 25 digital Ultra-Turrax; IKA, USA) again for 1 h, and filtered. The filtered slurry was dried at 80°C in an oven to obtain curcumin powder. The particle size was determined by using a high-resolution transmission electron microscope (JEM 2100F; JEOL, USA).