N n methylenebis acrylamide

1,3,2-Dioxathiolane
2,2-dioxide,
2-dimethylaminoethyl methacrylate (DMAEMA), and N,N′-methylenebis(acrylamide) (BIS) were purchased
from Tokyo Chemical Industry (Tokyo, Japan). 2,2-Azobis[2-(2-imidazoline-2-yl)propane]dihydrochloride
(VA-044) was purchased from FUJIFILM Wako Pure Chemical Co. (Osaka,
Japan). Hoechst 33342 and cell counting kit-8 were purchased from
DOJIN Laboratories (Kumamoto, Japan). Collagen type-I solution was
purchased from Nitta Gelatin, Inc. (Cellmatrix Type I-A, Osaka, Japan).

Ground pineapple leaf was
prepared according to the previously described method^{50 (link)} with slight modifications. Briefly, mature pineapple leaves
were cut into small pieces of 6 mm in length across the leaf long
axis. These were then ground using a motorized stone grinder, and
the mash was dried under the sun. The ground materials were received
from pineapple plantation in Ban Yang District, Phitsanulok, Thailand,
and PALF was separated by simple sieving. Acrylamide monomer (AM,
≥98.0%), sodium alginate (SA, viscosity = 15–25 cP,
1% in H₂O), and ionic cross-linker calcium chloride (CaCl₂, anhydrous) were purchased from Sigma-Aldrich (China and
United Kingdom). Potassium persulfate (KPS, 97.0%) was obtained from
Ajax Finechem (Australia). N,N′-methylenebisacrylamide
(MBA, ≥98.0%) from Tokyo Chemical Industry Co., Ltd. (Japan)
was used as a cross-linker. All chemicals were used without purification.