List of Articles زیست پزشکی

• Open Access Article
  • Abstract Page
  • Full-Text
  
  1 - Application of chitosan polymeric carriers as controlled drug delivery systems
  Milad Ghezelsofloo Abdulhamid Dehghani Soheila Ghasemi
  In recent decades, natural polymers, especially polysaccharides, have been used as carrier to deliver a wide range of therapeutic agents. Chitosan, the second most abundant natural polysaccharide after cellulose, is a biocompatible, biodegradable, hydrophilic, non-toxic More

  In recent decades, natural polymers, especially polysaccharides, have been used as carrier to deliver a wide range of therapeutic agents. Chitosan, the second most abundant natural polysaccharide after cellulose, is a biocompatible, biodegradable, hydrophilic, non-toxic, high bioavailability polymer with the ability to form films, gels, nanoparticles, microparticles, and granules. Chitosan is a linear polysaccharide obtained by deacetylation of chitin. Also, biodegradable chitosan in the human body is broken down into safe compounds (amino sugars) that are easily absorbed. Chitosan has hydroxyl and amine chemical functional groups that can be modified to achieve specific goals and turn it into a polymer with a wide range of potential applications. The aim of this paper is to provide insight into the potential applications of chitosan as a drug carrier. In the following, the use of chitosan to build deliverable sustainable delivery systems in other ways (oral, nasal, ocular, mucosal adhesion, buccal, and vaginal) is discussed. This report shows that research on chitosan-based systems containing different drugs for various therapeutic applications such as cancer treatment, gastrointestinal diseases, lung diseases, drug delivery to the brain and eye infections has increased in recent years.  Manuscript profile
• Open Access Article
  • Abstract Page
  • Full-Text
  
  2 - Metal additive manufacturing technology: A review of biomedical applications
  Sheida Esmaielzadeh
  Metal 3D printing is a layer-by-layer fabrication method used to manufacture 3D models of complex structures. This technology has multiple methods, materials, and equipment that bypassing many of the costs associated with traditional processes, equipment, and skills for More

  Metal 3D printing is a layer-by-layer fabrication method used to manufacture 3D models of complex structures. This technology has multiple methods, materials, and equipment that bypassing many of the costs associated with traditional processes, equipment, and skills for metal working, while creating free-form, near-net-shape 3D objects. This procedure is more accurately portrayed as additive manufacturing. Additive manufacturing’s attributes include print customization, low perunit cost for production, seamless interfacing with mainstream medical 3D imaging techniques, and feasibility to create freeform objects in materials that are biocompatible and biodegradable. The term 3D printing, in any case, is generally new and has been an active part of current developments in biomedical. Consequently, additive manufacturing is apposite for a wide range of biomedical applications including custom biocompatible implants that mimic the mechanical response of bone, biodegradable scaffolds with engineered degradation rate, medical surgical tools and biomedical instrumentation. This review surveys the materials, 3D printing methods and technologies, and biomedical applications of metal 3D printing. Manuscript profile
• Open Access Article
  • Abstract Page
  • Full-Text
  
  3 - Design and Simulation of a New Capacitance Multiplier with Adaptive Current Bias and Quasi-Floating Gate Technique with Electronic Tunability and High Linearity for Biomedical Applications
  Mohammad Aghaei Jeshvaghani Mehdi Dolatshahi Sayed Mohammad Ali Zanjani Mohammad Amin Honarvar
  Employing capacitance multipliers in low-frequency integrated circuits has a significant effect on reducing the chip size area. The main idea behind the proposed circuit in this paper is to use a folded current follower (FCF) structure to effectively reduce the equivale More

  Employing capacitance multipliers in low-frequency integrated circuits has a significant effect on reducing the chip size area. The main idea behind the proposed circuit in this paper is to use a folded current follower (FCF) structure to effectively reduce the equivalent series resistance (ESR) in the input stage. Furthermore, using an auxiliary circuit to adapt the bias current of the transistors and applying the necessary signals by the quasi-floating gate technique (QFG), are other approaches employed to reduce the static power consumption while properly increasing the linearity of the proposed circuit, which can be considered as other benefits of the proposed approach. On the other hand, to improve the linearity, negative feedback is used and necessary voltage is applied to the gate of the transistors in the current sampler. The “K” coefficient can be adjusted by the active method. Low input resistance and high output resistance as well as the reduced occupied silicon area are achieved based on the simulation results of the proposed circuit. The simulation results in 0.18 μm technology show that, with a 0.8 V power supply and base capacitor (Cb=1 pF), for 850 nW power consumption, a capacitor equivalent to 204 pF is achieved in the proposed approach. As another example, to realize the 101 pF capacitor with the supply as mentioned above and base capacitor, the proposed multiplier requires 6.3 times less area and 23 times more bandwidth than FCF, which shows the increased accuracy of the proposed design. In the proposed circuit, in the presence of a current adaptive circuit with an input signal range of 7 nA, the output current range is obtained as 1510 nA, While the output bias current is 100nA and the harmonic distortion value is obtained as 3.6%. The proposed circuit has the highest figure of merit 42.823 MHz/μW, which shows superiority in overall performance in comparison with other reported designs. Manuscript profile