ABSTRACT
We report the first nanoformulation of Hyaluronidase (Hyal) and its enhanced adjuvant effect over the free enzyme. Hyaluronic acid (HA) degrading enzyme Hyal was immobilized on 250 nm silica nanoparticles (SiNP) maintaining specific activity of the enzyme via the layer-by-layer self-assembly technique. This process was characterized by dynamic light scattering (DLS), zeta potential, infrared and UV-Vis spectroscopy, transmission electron microscopy (TEM) and enzymatic activity measurements. The nanoparticles were tested in vivo as adjuvants of carboplatin (CP), peritumorally injected in A375 human melanoma bearing mice and compared with the non-immobilized enzyme, on the basis of equal enzymatic activity. Alcian Blue staining of A375 tumors indicated large overexpression of hyaluronan. At the end of the experiment, tumor volume reduction with SiNP-immobilized Hyal was significantly enhanced compared to non-immobilized Hyal. Field emission scanning electron microscopy (FE-SEM) images together with energy dispersive X-ray spectroscopy (EDS) spectra confirmed the presence of SiNP on the tumor. We mean a proof of concept: this extracellular matrix (ECM) degrading enzyme, immobilized on SiNP, is a more effective local adjuvant of cancer drugs than the non-immobilized enzyme. This could prove useful in future therapies using other or a combination of ECM degrading enzymes.
Subject(s)
Antineoplastic Agents/administration & dosage , Carboplatin/administration & dosage , Hyaluronic Acid/metabolism , Melanoma/drug therapy , Nanoparticles/chemistry , Silicon Dioxide/chemistry , Skin Neoplasms/drug therapy , Animals , Drug Carriers/chemistry , Enzymes, Immobilized/chemistry , Enzymes, Immobilized/metabolism , Female , Humans , Hyaluronoglucosaminidase/chemistry , Hyaluronoglucosaminidase/metabolism , Melanoma/pathology , Mice , Mice, Nude , Porosity , Skin Neoplasms/pathology , Transplantation, HeterologousABSTRACT
Organized layer-by-layer nanostructured amperometric enzyme electrodes with self-contained redox polyelectrolyte mediators have shown important effects depending on the nature and charge of the adsorbed topmost layer. Adsorption of PVS causes the drop of the catalytic responses to negligible values due to hindrance in electron hopping and enzyme wiring.
Subject(s)
Electrons , Enzymes/chemistry , Adsorption , Aspergillus niger/enzymology , Biocatalysis , Electric Capacitance , Electric Conductivity , Electrochemistry , Electrodes , Enzymes/metabolism , Glucose Oxidase/chemistry , Glucose Oxidase/metabolism , Laccase/chemistry , Laccase/metabolism , Oxidation-Reduction , Polyamines/chemistry , Polyvinyls/chemistry , Siloxanes/chemistry , Trametes/enzymologyABSTRACT
We report a fully integrated core-shell nanoparticle system responsive to glucose. The system is comprised of self-assembled glucose oxidase and an osmium molecular wire on core-shell Au nanoparticles. Characterization of the functional nanoparticles by spectroscopy, quartz crystal microbalance and electrochemical techniques has shown that the catalytically active shell has a structure as designed and all components are active in the self-assembled multilayer shell. Furthermore, amperometric reagentless detection of glucose and contactless photonic biosensing by the Os(II) resonant Raman signal have been demonstrated. The enzymatic reduction of FAD by glucose and further reduction of the Raman silent Os(III) by FADH 2 yields a characteristic enzyme-substrate calibration curve in the millimolar range. Furthermore, coupling of electronic resonant Raman of the osmium complex with the SERS amplification by Au NPs plasmon resonance has been demonstrated which leads to an extra enhancement of the biosensor signal. We present a proof of concept extending the work done with planar surfaces to core-shell NPs as an advance in the design of glucose-responsive chemistry detected by SERS-like methods.
