Gelatin-loaded p(HEMA-GMA) cryogel for high-capacity immobilization of horseradish peroxidase

Figures & data

Figure 1. SEM images of p(HEMA-GMA) cryogel discs.

Table 1. Some properties of p(HEMA-GMA) cryogel discs.

Specific surface area	9.2 m^2/g
Porosity	65%
Pore size diameter	10–200 μm
Swelling degree	7.8 g H2O/g cryogel
Gelatin attachment	65.3 mg/g

Figure 2. Effect of pH on immobilization of HRP. Initial HRP concentration: 0.5 mg/ml; gelatin loading: 65.3 mg/g; T: 25°C.

Figure 3. Effect of temperature on immobilization of HRP. Initial HRP concentration: 0.5 mg/ml; gelatin loading: 65.3 mg/g; pH: 7.5.

Figure 4. Effect of initial HRP concentration on immobilization of HRP. Gelatin loading: 65.3 mg/g; pH: 7.5; T: 25°C.

Table 2. Langmuir and Freundlich adsorption isotherm constants for reversible immobilization of HRP.

	Experimental	Langmuir constants			Freundlich constants
Cryogel	Q (mg/g)	Qmax (mg/g)	b (mL/mg)	R^2	Qf	n	R^2
p(HEMA-GMA)/gelatin  cryogel discs	24.86	52.32	0.46	0.99	15.30	1.53	0.93

Table 3. The first- and second-order kinetic constants.

	Experimental	Pseudo-first order			Pseudo-second order
Equilibrium concentration (mg/mL)	Qeq (mg/g)	k1 (1/min)	qeq(mg/g)	R^2	k2 (g/mg.min)	qeq (mg/g)	R^2
0.50 mg/ml	9.60	0.02	6.23	0.26	0.01	13.62	0.99

Figure 5. Reusability of p(HEMA-GMA)/gelatin cryogel discs. Initial HRP concentration: 0.5 mg/ml; gelatin loading: 65.3 mg/g; pH: 7.5; T: 25°C. Phenol removal was carried out in the presence of 10 mg/l of phenol and 1 mM of H₂O₂ as an oxidant.