ATR‐FTIR measurements of albumin and fibrinogen adsorption: Inert versus calcium phosphate ceramics

Abstract

Arthritis, bone fracture, bone tumors and other musculoskeletal diseases affect millions of people across the world. Nowadays, inert and bioactive ceramics are used as bone substitutes or for bone regeneration. Their bioactivity is very much dictated by the way proteins adsorb on their surface. In this work, we compared the adsorption of albumin and fibrinogen on inert and calcium phosphates ceramics (CaPs) using attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) to follow in situ protein adsorption on these materials. To this effect, we developed a sol-gel technique to control the surface chemistry of an ATR-FTIR detector. Hydroxyapatite adsorbed more albumin and β-tricalcium phosphate adsorbed more fibrinogen. Biphasic calcium phosphate presented the lowest adsorption among CaP for both proteins, illustrating the effect of surface heterogeneities. Inert ceramics adsorbed a lower amount of both proteins compared with bioactive ceramics. A significant change was observed in the conformation of the adsorbed protein versus the surface chemistry. Hydroxyapatite produced a larger loss of α-helix structure on albumin and biphasic calcium phosphate reduced β-sheet percentage on fibrinogen. Inert ceramics produced large α-helix loss on albumin and presented weak interaction with fibrinogen. Zirconia did not adsorb albumin and titanium dioxide promoted huge denaturalization of fibrinogen.

Influence of different chemical treatments on the surface of Al2O3/ZrO2 nanocomposites during biomimetic coating

“…groups in nonstoichiometric HA and β-TCP). The positions of the peaks observed in the second derivative spectra (cm −1 ), within the phosphate regions (970-1200 cm −1 ), as well as their attributions in accordance to the literature, are summarized in Table 2 [11,12,28]. Overall, after 21 days of incubation, the percentages of the areas under the absorption bands in the regions between 1029 and 1035 cm −1 as well as between 1100 and 1008 cm −1 increased in the chemically untreated Al 2 O 3 /ZrO 2 nanocomposites and in those treated with H 3 PO 4 and HNO 3 .…”

“…As previously mentioned in this text, the crystal growth of the Table 2 Peak positions (cm −1 ) observed in the FTIR spectra of the second derivative in the regions typical of phosphates as well as their attributions according to data published in the literature [11,12,28]. αTCP, βTCP and HA phases on the surface depended on the different chemical treatments.…”

Poly (3‐hydroxybutyrate‐co‐3‐hydroxyvalerate)/fibrinogen/bredigite nanofibrous membranes and their integration with osteoblasts for guided bone regeneration

“…The spectra of PHBV membrane displays a peak at 1721 cm −1 responsible for C O stretching band, the peaks ranging 1230-1430 cm −1 and 835-955 cm −1 corresponds to various aliphatic C H vibrational bands, and the peaks for C O vibrational bands at 1170, 1125, and 1020 cm −1 . 17,24 In the spectra of blended PHBV/FG and PHBV/FG/BR membranes, two peaks at 1640 and 1530 cm −1 corresponded to the amide I and amide II bands of fibrinogen, respectively, and a broad peak at about 3350 cm −1 , which are characteristic peaks of peptides/protein structures 16,25 are observed, in addition to typical bands of PHBV. In the spectra of PHBV/FG/BR nanofibers, the peaks at 850 and 961 cm −1 attributed to stretching vibration of silicate structure and the peak at 507 cm −1 corresponded to Mg O bands appeared or their intensity increased, in addition to typical bands of PHBV and fibrinogen.…”

Polysaccharide–Protein Multilayers Based on Chitosan–Fibrinogen Assemblies for Cardiac Cell Engineering

“…[ 39–41 ] Fbg characteristic bands amide I and II are found at 1652 and 1541 cm –1 respectively. [ 42,43 ] Chit's amide II bending (1647–1650 cm –1 ) and NH bending (1535 cm –1 ) are compatible with the FTIR spectra although they are near Fbg’ amide I and II bands. [ 44,45 ] The characteristic bands generally increase in intensity upon successive depositions, which shows the multilayer build‐up.…”