Prerpints.org logo

You are currently viewing a beta version of our website. If you spot anything unusual, kindly let us know.

Leave Feedback
Preprint
Article

Investigating the Biochemical Stability and Kinetic Performances of SiO2@AuNPs Nanocomposite as High Throughput Peroxidase Alternatives

Altmetrics

Downloads

79

Views

26

Comments

0

This version is not peer-reviewed

Submitted:

10 August 2023

Posted:

11 August 2023

You are already at the latest version

Alerts
Abstract
In this study, considering the peroxidase-like activity of the SiO2@AuNPs nanocomposite, their biochemical properties including, pH stability, cycling stability, shelf stability, and kinetic parameters were investigated. The results revealed that the as-mentioned SiO2@AuNPs nanocomposite reveal its maximal activity at pH=4.0 along with saving 83.3% of its maximal activity at pH=5.0. Besides, the reusability and shelf-storage studies exhibited that the SiO2@AuNPs nanocomposite retained 90% and 100% of its initial activity after 5 operational cycles and 30 days of storage, in order. The kinetic parameters of the as-prepared nanozymes were calculated using Menten kinetic model, revealing a Vmax of 1.35 µM min-1 and a Km as low as 0.06 mM for the SiO2@AuNPs nanocomposite. Based on the results of this work, the as-prepared SiO2@AuNPs nanocomposite with intrinsic peroxidase-like activity shows high substrate affinity and catalytic efficiency along with excellent cycling- and shelf-stability, making them suitable for application in peroxidase-mediated reactions instead of the native enzyme.
Keywords: 
Subject: Chemistry and Materials Science  -   Analytical Chemistry

1. Introduction

Importance and practical application of nanotechnology in modern life lead to design and synthesis of different nanomaterials with optical [1,2,3], catalytic [4,5], medical [6], anti-cancer features [7], or anti-bacterial [8,9] characteristics such as carbon and quantum dots [10,11], metal-based nanoparticles [12,13], magnetic nanoparticles [14], metal oxide nanoparticle [15], and metal-organic frameworks [16,17], etc. Among various nanoparticles with different properties, recently, nanomaterials with enzyme-like properties, called nanozymes have been widely utilized for catalyzing industrial, clinical, and environmental enzyme-mediated reactions under harsh conditions [18,19,20,21]. The most significant advantage of these nanozymes compared to the native enzymes is their lower cost, higher efficiency, and especially, their high cycling stability and recyclability [19,22]. Up to now, different nanoparticles with intrinsic peroxidase-like activity were designed and synthesized, for instance, Mn3 O4 nanozymes [23], Cu-CuFe2O4 nanozymes [24], BSA-stabilized manganese phosphate nanoflower [25], BSA-stabilized manganese dioxide nanoparticles [26], silica-coated-magnetic nanoparticles [27], carbon nanozymes [28], MnO2 nanoparticles [29], self-cascade pyrite nanozymes [30], Fe3O4 nanozymes [31], metal-organic frameworks [32], gold nanozymes [33], S/N codoped carbon nanozymes [34], and silver nanoparticles [35]. Among the different nanomaterials with excellent peroxidase-like activity, gold-based nanozymes had been widely for developing nanozyme-based sensors [36,37], nanozyme-based cancer treatment [38], and nanozyme-mediated dye degradation [39]. Hence, evaluation of their biochemical features and enzyme-like properties is important for developing nanozyme-based systems with better figures of merit. In this regard, recently, our research group reported a research article on the investigation of biochemical behaviors of BSA-stabilized gold nanoparticles [40]. Considering our best knowledge, there is no report on the specific enzyme-like activity, biochemical stability, and kinetic performances of SiO2@AuNPs nanocomposites. Hence, herein, the biochemical properties (pH-, cycling-, & shelf- stability) and kinetics parameters of SiO2@AuNPs nanocomposite as the high throughput peroxidase alternatives were evaluated. The as-synthesized nanocomposite was characterized by the TEM imaging method. Besides, the peroxidase-like activity of the as-prepared SiO2@AuNPs nanocomposite was quantified using the standard peroxidase assay. Considering the high peroxidase-like activity of the SiO2@AuNPs nanocomposite, their biochemical properties including, pH stability, cycling stability, shelf stability, and kinetic parameters were investigated. Based on the results of this work, the as-prepared SiO2@AuNPs nanocomposite with intrinsic peroxidase-like activity shows high substrate affinity and catalytic efficiency along with excellent cycling- and shelf-stability, making them suitable for application in peroxidase-mediated reactions instead of the native enzyme.

2. Experimental

2.1. Synthesis of SiO2@Au nanocomposite

In a typical experiment, 1.0 mL of HAuCl4, 10.0 μL tetrakis(hydroxymethyl)phosphonium chloride, and 500.0 μL NaOH (2.0 M) were introduced in 50.0 mL deionized water. The resulting mixture was stirred for about 1.0 hour to prepare the colloidal gold solution. To synthesize the amino-functional SiO2 NPs, 1.5 mL of TEOS was added into 40.0 mL of pure ethanol, followed by the addition of 3.0 mL of NH4OH. The mixture was stirred for about 20.0 hours. Afterward, 20.0 mg of the resulting precipitate was treated with 600.0 μL of APTES for preparation of the final product. Afterward, 10.0 mg of the amino-functional SiO2 NPs were incubated with a solution of colloidal gold (prepared in section 2.3) for about 12.0 hours. Afterward, the product was separated from the reaction media upon centrifuge at 10000 rpm for 30.0 min. The resulting product was dispersed in 1 mg mL-1 of PVP (stabilizer) aqueous solution, followed by the addition of 60.0 μL of HAuCl4 (10.0 mM) and 120.0 μL of 10.0 mM ascorbic acid (reducing agent) into the reaction media. The synthesis process was followed by stirring the above-mentioned mixture for about 5 min. Afterward, the resulting SiO2@AuNPs nanocomposite was collected, washed, and then dried at room temperature.

2.5. Nanozyme activity assay

In a typical assay, 100.0 µL of 1.0 mM TMB was introduced into 1.0 mL acetate buffer (pH=4.0) containing the SiO2@Au nanocomposite, followed by adding 100.0 μL of 100 µL of 2.0 M H2O2 solution, The reaction mixture was incubated at ambient conditions for about 0.5 hours and then the oxidation reaction was terminated by addition of sulfuric acid into the reaction media. Afterward, the spectrum of the colored product was recorded and the λmax at 450.0 nm of the resulted TMB dimine was utilized for calculating the enzyme activity in μM min-1, considering that the molar absorption coefficient of TMB dimine at 450.0 nm is about 5.9 × 104 mol-1 cm-1. It is mentionable that the relative and residual nanozymatic activity of the as-prepared nanocomposite was calculated by the following formulas [41,42];
Residual activity (%) = (Activity/Activity of control) ×100
Relative activity (%) = (Activity/Maximal activity) ×100

3. Results and discussion

3.1. pH stability of SiO2@Au nanocomposite
The pH effect on the enzyme-like activity of the as-prepared SiO2@AuNPs nanocomposite was evaluated by measuring its relative activity over a pH range of 3.0-7.0. The above-mentioned studies were performed to provide insight into the stability of the enzyme-like the as-prepared SiO2@AuNPs nanocomposite against environmental pH changes (Figure 1). The results shown in this figure exhibited that the as-prepared SiO2@AuNPs nanocomposite show its maximum enzyme-like activity at pH =4.0 and then its activity was slightly decreased by increasing the pH of media, reaching 83.3% at pH=5.0. The activity of the as-prepared SiO2@AuNPs nanocomposite reached 6.6% of its maximum value at pH=7.0.

3.2. Cycling stability of SiO2@Au nanocomposite

To evaluate the cycling stability of the as-prepared SiO2@AuNPs nanocomposite, the reusability studies were performed as a reliable way for proving the recoverability and cycling stability of nanocatalysts [5]. To do this, the activity of the as-prepared nanocomposite in the first operational time was considered 100% and used as the control for calculating the residual activity of nanocomposite in successive operational cycles. The plot of the residual activity of the nanocomposite as a function of operational times was shown in Figure 2, as shown in this figure, the as-prepared nanozymes can save their initial activity during 4 operational cycles. After that, their activity slightly decreased and reached 90% of their initial activity at the 5th operational cycle. Considering these results, it can be concluded that the as-prepared SiO2@AuNPs nanocomposite can be utilized as a high-throughput nanozymes with excellent reusability and cycling stability.

3.3. Storage stability of SiO2@Au nanocomposite

The shelf-life (shelf stability) of the as-prepared SiO2@AuNPs nanocomposite was investigated upon their storage in acetate buffer (pH=4.0) at ambient conditions for about one month. The activity of the as-prepared nanocomposite on the first day of storage was considered 100% and used as the control for calculating the residual activity of the nanocomposite. Thereafter, the residual activity of the nanozymes was determined in different time intervals during the storage as an index for estimating their shelf stability. The plot of residual activity of the nanocomposite as a function of storage time (day) was shown in Figure 3, revealing that the as-prepared SiO2@AuNPs nanocomposite save 100% of their initial activity after 30 days of storage at ambient conditions. Considering these results, it can be concluded that the as-synthesized SiO2@AuNPs nanocomposite can be used as excellent enzyme alternatives with high shelf stability as a significant advantage from a practical point of view.

3.4. Kinetic performances of SiO2@AuNPs nanocomposite

Kinetic studies were carried out to calculate the kinetic parameters of the as-prepared SiO2@AuNPs nanocomposite toward 2-electron reversible oxidation of TMB. In fact, the kinetic parameters of an enzyme were previously well defined with numeric values including affinity constant (Km) and maximum enzymatic velocity (Vmax) utilizing the Michaelis–Menten steady-state kinetics model. The Vmax value reflects the intrinsic properties of an enzyme or nanozyme and is defined as the highest possible rate of the nanozyme-catalyzed reaction when all enzyme molecules or all nanozyme particles are saturated with the substrate which pointed to the catalytic efficiency of an enzyme or nanozyme. Hence, the higher value of Vmax for an enzymatic/nanozymatic reaction can be assigned to the higher catalytic efficiency of the enzyme or nanozyme [40,41,42]. In contrast, the affinity of the substrate of an enzyme or nanozyme for interaction with its active site is represented by the Km, as reported [40]. In fact, the lower values of Km pointed to the higher affinity of the substrate for binding to the enzyme/nanozyme active site/nodes [17,40]. Therefore, to quantify the kinetics parameters of the as-prepared SiO2@AuNPs nanocomposite, the Michaelis–Menten saturation curve was obtained via plotting the nanozymatic reaction velocity as a function of the substrate (TMB) concertation (Figure 4A). As seen in Figure 6A, the reaction rate of the SiO2@AuNPs nanocomposite-mediated oxidation reaction was increased by increasing the TMB concertation and then reaching a steady-state condition. For accurate estimation of Km and Vmax of the SiO2@AuNPs nanocomposite-mediated oxidation reaction, the Lineweaver–Burk plot was also constructed for the SiO2@AuNPs nanocomposite-mediated reaction (Figure 4B). The results revealed a Vmax of 1.35 µM min-1 and a Km as very low as 0.06 mM for the SiO2@AuNPs nanocomposite. Considering the low Km value of the as-synthesized nanocomposite, it can be concluded that the as-prepared nanocomposite shows high substrate affinity, as reported [17,41]. Besides, obtaining a Vmax of 1.35 µM min-1, revealed that the as-prepared nanocomposite has a very good catalytic efficiency.

4. Conclusions

In this study, considering the peroxidase-like activity of the SiO2@AuNPs nanocomposite, their biochemical properties including, pH stability, cycling stability, shelf stability, and kinetic parameters were investigated. The results revealed that the as-mentioned SiO2@AuNPs nanocomposite reveal its maximal activity at pH=4.0 along with saving 83.3% of its maximal activity at pH=5.0. Besides, the reusability and shelf-storage studies exhibited that the SiO2@AuNPs nanocomposite retained 90% and 100% of its initial activity after 5 operational cycles and 30 days of storage, in order. The kinetic parameters of the as-prepared nanozymes were calculated using Menten kinetic model, revealing a Vmax of 1.35 µM min-1 and a Km as low as 0.06 mM for the SiO2@AuNPs nanocomposite. Based on the results of this work, the as-prepared SiO2@AuNPs nanocomposite with intrinsic peroxidase-like activity shows high substrate affinity and catalytic efficiency along with excellent cycling- and shelf-stability, making them suitable for application in peroxidase-mediated reactions instead of the native enzyme.

Acknowledgments

The authors gratefully thank the Hormozi Laboratory of Chemistry and Biochemistry (Zabol, Iran) for the support of this work.

Conflict of interest

None.

References

  1. Kelly, K. L., Coronado, E., Zhao, L. L., & Schatz, G. C. (2003). The optical properties of metal nanoparticles: the influence of size, shape, and dielectric environment. The Journal of Physical Chemistry B, 107(3), 668-677. [CrossRef]
  2. Dehghani Z., Akhond M., Hormozi Jangi S.R., Absalan G. (2024) Highly sensitive enantioselective spectrofluorimetric determination of R-/S-mandelic acid using l-tryptophan-modified amino-functional silica-coated N-doped carbon dots as novel high-throughput chiral nanoprobes, Talanta, 266, 1, 124977. [CrossRef]
  3. Hormozi Jangi, S. R., & Gholamhosseinzadeh, E. (2023). Developing an ultra-reproducible and ultrasensitive label-free nanoassay for L-methionine quantification in biological samples toward application in homocystinuria diagnosis. Chemical Papers, 1-13. [CrossRef]
  4. Hormozi Jangi, S. R. (2023). Low-temperature destructive hydrodechlorination of long-chain chlorinated paraffins to diesel and gasoline range hydrocarbons over a novel low-cost reusable ZSM-5@ Al-MCM nanocatalyst: a new approach toward reuse instead of common mineralization. Chemical Papers, 1-15. [CrossRef]
  5. Hormozi Jangi S. R.; Akhond M. (2020). High throughput green reduction of tris (p-nitrophenyl) amine at ambient temperature over homogenous AgNPs as H-transfer catalyst. Journal of Chemical Sciences, 132, 1-8. [CrossRef]
  6. Singh, R., & Nalwa, H. S. (2011). Medical applications of nanoparticles in biological imaging, cell labeling, antimicrobial agents, and anticancer nanodrugs. Journal of biomedical nanotechnology, 7(4), 489-503. [CrossRef]
  7. Shi, Y., Shan, S., Li, C., Song, X., Zhang, C., Chen, J., ... & Xiong, J. (2020). Application of the tumor site recognizable and dual-responsive nanoparticles for combinational treatment of the drug-resistant colorectal cancer. Pharmaceutical Research, 37, 1-14. [CrossRef]
  8. Amany, A., El-Rab, S. F. G., & Gad, F. (2012). Effect of reducing and protecting agents on size of silver nanoparticles and their anti-bacterial activity. Der Pharma Chemica, 4(1), 53-65.
  9. Rajasekaran, J., & Viswanathan, P. (2023). Anti-bacterial and antibiofilm properties of seaweed polysaccharide-based nanoparticles. Aquaculture International, 1-25. [CrossRef]
  10. Li, G., Liu, Z., Gao, W., & Tang, B. (2023). Recent advancement in graphene quantum dots based fluorescent sensor: Design, construction and bio-medical applications. Coordination Chemistry Reviews, 478, 214966. [CrossRef]
  11. Hormozi Jangi, S. R., & Akhond, M. (2021). Ultrasensitive label-free enantioselective quantification of d-/l-leucine enantiomers with a novel detection mechanism using an ultra-small high-quantum yield N-doped CDs prepared by a novel highly fast solvent-free method. Sensors and Actuators B: Chemical, 339, 129901. [CrossRef]
  12. Jangi, S. R. H. (2023). Determining kinetics parameters of bovine serum albumin-protected gold nanozymes toward different substrates. Qeios. [CrossRef]
  13. Hormozi Jangi, S. R. (2023). Effect of daylight and air oxygen on nanozymatic activity of unmodified silver nanoparticles: Shelf-stability. Qeios. [CrossRef]
  14. Dongsar, T. T., Dongsar, T. S., Abourehab, M. A., Gupta, N., & Kesharwani, P. (2023). Emerging application of magnetic nanoparticles for breast cancer therapy. European Polymer Journal, 111898. [CrossRef]
  15. Carrapiço, A., Martins, M. R., Caldeira, A. T., Mirão, J., & Dias, L. (2023). Biosynthesis of metal and metal oxide nanoparticles using microbial cultures: Mechanisms, antimicrobial activity and applications to cultural heritage. Microorganisms, 11(2), 378. [CrossRef]
  16. Hormozi Jangi, S. R. (2023). Synthesis and characterization of magnesium-based metal-organic frameworks and investigating the effect of coordination solvent on their biocompatibility. Chemical Research and Nanomaterials, 1(4), 1-9.
  17. Hormozi Jangi, S. R., & Akhond, M. (2021). High throughput urease immobilization onto a new metal-organic framework called nanosized electroactive quasi-coral-340 (NEQC-340) for water treatment and safe blood cleaning. Process Biochemistry, 105, 79-90. [CrossRef]
  18. Li, W., Chen, B., Zhang, H., Sun, Y., Wang, J., Zhang, J., & Fu, Y. (2015). BSA-stabilized Pt nanozyme for peroxidase mimetics and its application on colorimetric detection of mercury (II) ions. Biosensors and Bioelectronics, 66, 251-258. [CrossRef]
  19. Hormozi Jangi, A. R., Hormozi Jangi, M. R., & Hormozi Jangi, S. R. (2020). Detection mechanism and classification of design principles of peroxidase mimic based colorimetric sensors: A brief overview. Chinese Journal of Chemical Engineering, 28(6), 1492-1503. [CrossRef]
  20. Hormozi Jangi, S. R., & Dehghani, Z. (2023). Spectrophotometric quantification of hydrogen peroxide utilizing silver nanozyme. Chemical Research and Nanomaterials 2 (1), 15-23.
  21. Jangi, S. R. H. (2023). Introducing a High Throughput Nanozymatic Method for Eco-Friendly Nanozyme-Mediated Degradation of Methylene Blue in Real Water Media. Sustainable Chemical Engineering, 90-99. [CrossRef]
  22. Huang, Y., Ren, J., & Qu, X. (2019). Nanozymes: classification, catalytic mechanisms, activity regulation, and applications. Chemical reviews, 119(6), 4357-4412. [CrossRef]
  23. Lu, L., Huang, M., Huang, Y., Corvini, P. F. X., Ji, R., & Zhao, L. (2020). Mn 3 O 4 nanozymes boost endogenous antioxidant metabolites in cucumber (Cucumis sativus) plant and enhance resistance to salinity stress. Environmental Science: Nano, 7(6), 1692-1703. [CrossRef]
  24. Xia, F., Shi, Q., & Nan, Z. (2020). Facile synthesis of Cu-CuFe 2 O 4 nanozymes for sensitive assay of H 2 O 2 and GSH. Dalton Transactions, 49(36), 12780-12792. [CrossRef]
  25. Dega, N. K., Ganganboina, A. B., Tran, H. L., Kuncoro, E. P., & Doong, R. A. (2022). BSA-stabilized manganese phosphate nanoflower with enhanced nanozyme activity for highly sensitive and rapid detection of glutathione. Talanta, 237, 122957. [CrossRef]
  26. Liu, J., Gao, J., Zhang, A., Guo, Y., Fan, S., He, Y., ... & Cheng, Y. (2020). Carbon nanocage-based nanozyme as an endogenous H 2 O 2-activated oxygenerator for real-time bimodal imaging and enhanced phototherapy of esophageal cancer. Nanoscale, 12(42), 21674-21686. [CrossRef]
  27. Hormozi Jangi, S. R., Davoudli, H. K., Delshad, Y., Hormozi Jangi, M. R., & Hormozi Jangi, A. R. H. (2020). A novel and reusable multinanozyme system for sensitive and selective quantification of hydrogen peroxide and highly efficient degradation of organic dye. Surfaces and Interfaces, 21, 100771. [CrossRef]
  28. Sun, H., Zhou, Y., Ren, J., & Qu, X. (2018). Carbon nanozymes: enzymatic properties, catalytic mechanism, and applications. Angewandte Chemie International Edition, 57(30), 9224-9237. [CrossRef]
  29. Hormozi Jangi, S. R., Akhond, M., & Absalan, G. (2020). A field-applicable colorimetric assay for notorious explosive triacetone triperoxide through nanozyme-catalyzed irreversible oxidation of 3, 3′-diaminobenzidine. Microchimica Acta, 187, 431. [CrossRef]
  30. Meng, X., Li, D., Chen, L., He, H., Wang, Q., Hong, C., ... & Fan, K. (2021). High-performance self-cascade pyrite nanozymes for apoptosis–ferroptosis synergistic tumor therapy. ACS nano, 15(3), 5735-5751. [CrossRef]
  31. Dong, H., Du, W., Dong, J., Che, R., Kong, F., Cheng, W., ... & Zhang, Y. (2022). Depletable peroxidase-like activity of Fe3O4 nanozymes accompanied with separate migration of electrons and iron ions. Nature Communications, 13(1), 5365. [CrossRef]
  32. Hormozi Jangi, S. R., & Akhond, M. (2020). Synthesis and characterization of a novel metal-organic framework called nanosized electroactive quasi-coral-340 (NEQC-340) and its application for constructing a reusable nanozyme-based sensor for selective and sensitive glutathione quantification. Microchemical Journal, 158, 105328. [CrossRef]
  33. Hormozi Jangi, S. R., Akhond, M., & Absalan, G. (2020). A novel selective and sensitive multinanozyme colorimetric method for glutathione detection by using an indamine polymer. Analytica Chimica Acta, 1127, 1-8. [CrossRef]
  34. Chen, Y., Jiao, L., Yan, H., Xu, W., Wu, Y., Wang, H., ... & Zhu, C. (2020). Hierarchically porous S/N codoped carbon nanozymes with enhanced peroxidase-like activity for total antioxidant capacity biosensing. Analytical Chemistry, 92(19), 13518-13524. [CrossRef]
  35. Hormozi Jangi, S. R., & Dehghani, Z. (2023). Kinetics and biochemical characterization of silver nanozymes and investigating impact of storage conditions on their activity and shelf-life. Chemical Research and Nanomaterials, 1(4), 25-33.
  36. Zhou, X., Wang, M., Chen, J., & Su, X. (2022). Cascade reaction biosensor based on Cu/N co-doped two-dimensional carbon-based nanozyme for the detection of lactose and β-galactosidase. Talanta, 245, 123451. [CrossRef]
  37. Akhond, M., Hormozi Jangi, S. R., Barzegar, S., & Absalan, G. (2020). Introducing a nanozyme-based sensor for selective and sensitive detection of mercury (II) using its inhibiting effect on production of an indamine polymer through a stable n-electron irreversible system. Chemical Papers, 74, 1321-1330.blood. [CrossRef]
  38. Zeng, X., Ruan, Y., Chen, Q., Yan, S., & Huang, W. (2023). Biocatalytic cascade in tumor microenvironment with a Fe2O3/Au hybrid nanozyme for synergistic treatment of triple negative breast cancer. Chemical Engineering Journal, 452, 138422. [CrossRef]
  39. Ahmadi-Leilakouhi, B., Hormozi Jangi, S. R., & Khorshidi, A. (2023). Introducing a novel photo-induced nanozymatic method for high throughput reusable biodegradation of organic dyes. Chemical Papers, 77(2), 1033-1046. [CrossRef]
  40. Hormozi Jangi, S. R. (2023). Evaluation of Biochemical Behavior and Stability of Gold Nanoparticles with High Intrinsic Peroxidase-Like Activity. Petro Chem Indus Intern, 6(4), 234-239. [CrossRef]
  41. Hormozi Jangi, S. R., Akhond, M., & Dehghani, Z. (2020). High throughput covalent immobilization process for improvement of shelf-life, operational cycles, relative activity in organic media and enzymatic kinetics of urease and its application for urea removal from water samples. Process Biochemistry, 90, 102-112. [CrossRef]
  42. Jangi, S. R. H., & Akhond, M. (2022). Introducing a covalent thiol-based protected immobilized acetylcholinesterase with enhanced enzymatic performances for biosynthesis of esters. Process Biochemistry, 120, 138-155. [CrossRef]
  43. Seong, B., Kim, J., Kim, W., Lee, S. H., Pham, X. H., & Jun, B. H. (2021). Synthesis of Finely Controllable Sizes of Au Nanoparticles on a Silica Template and Their Nanozyme Properties. International Journal of Molecular Sciences, 22(19), 10382. [CrossRef]
Preprints 82156 g001
Figure 1. The effect of pH on the enzyme-like activity of the as-prepared SiO2@AuNPs nanocomposite.
Figure 1. The effect of pH on the enzyme-like activity of the as-prepared SiO2@AuNPs nanocomposite.
Preprints 82156 g001
Preprints 82156 g002
Figure 2. Reusability of the as-prepared SiO2@AuNPs nanocomposite as peroxidase mimics.
Figure 2. Reusability of the as-prepared SiO2@AuNPs nanocomposite as peroxidase mimics.
Preprints 82156 g002
Preprints 82156 g003
Figure 3. Shelf-life of the as-prepared SiO2@AuNPs nanocomposite as peroxidase mimics.
Figure 3. Shelf-life of the as-prepared SiO2@AuNPs nanocomposite as peroxidase mimics.
Preprints 82156 g003
Preprints 82156 g004
Figure 4. (A) Michaelis–Menten curve and (B) Lineweaver–Burk plot for the as-prepared SiO2@AuNPs nanocomposite as peroxidase mimics.
Figure 4. (A) Michaelis–Menten curve and (B) Lineweaver–Burk plot for the as-prepared SiO2@AuNPs nanocomposite as peroxidase mimics.
Preprints 82156 g004
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.
Copyright: This open access article is published under a Creative Commons CC BY 4.0 license, which permit the free download, distribution, and reuse, provided that the author and preprint are cited in any reuse.
Enzymes@ZIF-8 Nanocomposites with Protection Nanocoating: Stability and Acid-Resistant Evaluation

Yuxiao Feng

et al.

Polymers,

2018

Co-immobilization of an Enzyme System on a Metal-Organic Framework to Produce a More Effective Biocatalyst

Raneem Ahmad

et al.

Catalysts,

2020

Enhancement of Thermostability of Aspergillus flavus Urate Oxidase by Immobilization on the Ni-Based Magnetic Metal–Organic Framework

Neda Motamedi

et al.

Nanomaterials,

2021

Prerpints.org logo

Preprints.org is a free preprint server supported by MDPI in Basel, Switzerland.

facebook logotwitter logolinkedin logo
MDPI Initiatives
Important Links
Subscribe

Disclaimer

Terms of Use

Privacy Policy

© 2024 MDPI (Basel, Switzerland) unless otherwise stated