Use of quartz crystal nanobalance to study the binding and stabilization of albumin and doxycycline on a thin layer of hydroxyapatite

This study reports the use of quartz crystal nanobalance (QCN) to study the adsorption of two model molecules namely albumin and doxycycline by hydroxyapatite (HA). The work focuses on the deposition of a stable coating of HA on the quartz crystal, modification of the coating using doxycycline and its subsequent effects on albumin adsorption. The uniformity and thickness of the HA coating has been studied using atomic force microscopy (AFM). The functional groups to ascertain the presence of the selected moieties have been characterized by Raman spectroscopy. The results indicate that the mass of albumin deposited on the surface of the HA coated quartz crystal functionalized with doxycycline shows a substantial increase when compared to the standard HA coated quartz crystal. The adsorbed albumin has also been found to be retained for an enhanced period of time. This surface immobilization of doxycycline and subsequent albumin adsorption seem to be a promising approach to confer biomaterials with antithrombogenic and antibacterial surfaces.

Highlights► Hydroxyapatite (HA) was coated on quartz crystal by deposition technique. ► Albumin adsorption on HA coated quartz was monitored by quartz crystal nanobalance. ► Doxycycline used to facilitate as specific interaction sites for albumin binding. ► Albumin adsorption on HA coated quartz immobilized with doxycycline was monitored by quartz crystal nanobalance. ► The albumin deposited shows a substantial increase and is retained for an enhanced period of time.