Innovative materials were manufactured via the combination of chitin and lignin,

Innovative materials were manufactured via the combination of chitin and lignin, and the immobilization of lipase from [8,9,10]. spectra of chitin-lignin composite and lipase (a) and selected products following 24 h of enzyme immobilization (b), in two different spectral range. Table 1 Maximal vibrational wavenumbers (cm?1) attributed to lipase from and expressed 66547-09-9 IC50 like a C:O:N molar percentage is 61:25:14 [55]. These ideals are in good agreement with the percentage obtained in the present study for the surface of lipase, namely 58:31:11. Similar good agreement is acquired for the surface composition of the chitin-lignin matrix, which was reported previously [53]. The oxygen-carbon percentage close to 0.5 acquired for chitin-lignin, as well as the surface composition of the matrix, are very close to the values observed for nanocrystalline chitin [56]. Since the elemental composition of lignin differs significantly from your percentage observed here, it is concluded that the surface of the support matrix is composed primarily of chitin. The nitrogen-carbon percentage is almost twice as high for the lipase as for the chitin-lignin material. Therefore an increase with this parameter can be used as an indication for successful enzyme immobilization, as reported previously [57]. Indeed the N/C percentage raises from 0.10 for the pure chitin-lignin matrix to 0.12 for the sample after immobilization. The elemental analysis of samples before and after immobilization, as explained in Section 2.1.3., shows an increase of approximately 20% in the nitrogen content material after enzyme immobilization. This is corroborated by XPS data. This increase in nitrogen concentration following a immobilization process is definitely taken as indirect evidence of successful lipase immobilization. Evaluation of the 66547-09-9 IC50 chemical composition of the surface of the examined materials is based mainly on analysis of the XPS C 1s maximum. The spectra have a relatively complex profile (Number 3). Deconvolution of the experimental data was performed using a model consisting of four basic components of the C 1s transition: C1CC4. Component C1, having a binding energy of 66547-09-9 IC50 284.4 0.1 eV, corresponds essentially to non-functionalized carbon atoms located in the aromatic rings expected to Cd63 be in the lignin structure. Component C2, having a binding energy of 284.8 eV, is attributed to all other non-functionalized sp2 and sp3 carbon atoms, bonded either to other carbon or to hydrogen atoms. Component C3, shifted by 1.4 0.2 eV from component C2 in the direction of increasing binding energies, is attributed to a set of groups having a carbon atom bonded to one atom of oxygen or nitrogen. These include the following practical groups which are presumed to be present in the analyzed materials: C-O-C, C-OH, C-N-C, C-NH2. Component C4, shifted by 2.9 0.2 eV from component C2 in the direction of increasing binding energies, also corresponds to a set of functional organizations: C=O, O-C-O, N-C-O and N-C=O. The binding energy interpretations given above are based on the energy shifts given in Appendix E [58]. A relative surface practical group composition from decomposition 66547-09-9 IC50 of the C 1s transmission is given in Table 4. The total C 1s maximum intensity is taken as 100. Number 3 The XPS C 1s spectra for chitin-lignin (a); lipase (b); and the chitin-lignin + lipase product (c). Table 4 Distribution of practical groups calculated on the basis of the deconvolution model of the XPS C 1s maximum. Since lipase consists of a relatively 66547-09-9 IC50 small number of aromatic rings, originating from amino acids such as phenylalanine or tyrosine [55], the component C1 is not regarded as in the deconvolution of the C 1s spectrum for the compound. Component C2 prevails in.