Delivery of drugs with controlled temporal profiles is essential for wound treatment and regenerative medicine applications. For example, bacterial infection is a key challenge in the treatment of chronic and deep wounds. Current treatment strategies are based on systemic administration of high doses of antibiotics, which result in side effects and drug resistance. On-demand delivery of drugs with controlled temporal profile is highly desirable. Here, we have developed thermally controllable, antibiotic-releasing nanofibrous sheets. Poly(glycerol sebacate)- poly(caprolactone) (PGS-PCL) blends were electrospun to form elastic polymeric sheets with fiber diameters ranging from 350 to 1100 nm and substrates with a tensile modulus of approximately 4-8 MPa. A bioresorbable metallic heater was patterned directly on the nanofibrous substrate for applying thermal stimulation to release antibiotics on-demand. In vitro studies confirmed the platform’s biocompatibility and biodegradability. The released antibiotics were potent against tested bacterial strains. These results may pave the path toward developing electronically controllable wound dressings that can deliver drugs with desired temporal patterns.

Thin films have a great impact on the modern era of technology. Thin films are considered as backbone for advanced applications in the various fields such as optical devices, environmental applications, telecommunications devices, energy storage devices, and so on . The crucial issue for all applications of thin films depends on their morphology and the stability. The morphology of the thin films strongly hinges on deposition techniques. Thin films can be deposited by the physical and chemical routes. In this chapter, we discuss some advance techniques and principles of thin-film depositions. The vacuum thermal evaporation technique, electron beam evaporation, pulsed-layer deposition, direct current/radio frequency magnetron sputtering, and chemical route deposition systems will be discussed in detail.

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Electrospun scaffolds of poly(glycerol sebacate)/poly(ε-caprolactone) (PGS/PCL) have been used for engineered tissues due to their desirable thermal and mechanical properties as well as their tunable degradability.

Oil fly ash has been reported to be a good source for the production of carbon nanotubes (CNTs). Recently, these CNTs were evaluated as lubricant additives in sunflower base oil and were found to exhibit excellent tribological properties. In this work, these CNTs were tested as lubricant additives in 100SN, 500SN and 150BS Saudi Aramco base oils. The results on other commercial carbon nanostructures like multiwall and single wall CNTs and graphene are also included in this study for comparison. Excellent tribological performance was obtained with CNTs of fly ash at a very small concentration. The observed reduction in values of the friction coefficient between two metallic surfaces using these CNTs was found to be superior to those of other carbon nanomaterials. The value of the friction coefficient was reduced by around 20% at a concentration of 0.1 wt%. These values were also investigated as a function of load, speed and temperature. The rheological behaviour showed that the viscosity of the 0.1 wt% CNTsimpregnated 500SN oil is almost invariant compared to that of the pure one. It is therefore suggested that CNTs of fly ash may be a good lubricant additive to minimize the friction and improve the fuel economy.

Electrospun micro- and nanofibrous poly(glycerol sebacate)-poly(ε-caprolactone) (PGS-PCL) substrates have been extensively used as scaffolds for engineered tissues due to their desirable mechanical properties and their tunable degradability. In this study, we fabricated micro/nanofibrous scaffolds from a PGS-PCL composite using a standard electrospinning approach and then coated them with silver (Ag) using a custom radio frequency (RF) sputtering method. The Ag coating formed an electrically conductive layer around the fibers and decreased the pore size. The thickness of the Ag coating could be controlled, thereby tailoring the conductivity of the substrate. The flexible, stretchable patches formed excellent conformal contact with surrounding tissues and possessed excellent pattern-substrate fidelity. In vitro studies confirmed the platform’s biocompatibility and biodegradability. Finally, the potential controlled release of the Ag coating from the composite fibrous scaffolds could be beneficial for many clinical applications.

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