Yazar "Irfan, Muhammad" seçeneğine göre listele

Listeleniyor 1 - 2 / 2
  • Küçük Resim
    Öğe
    A novel high GainWideband MIMO antenna for 5G millimeter wave applications
    (MDPI, 2020) Sehrai, Daniyal Ali; Abdullah, Mujeeb; Altaf, Ahsan; Kiani, Saad Hassan; Muhammad, Fazal; Tufail, Muhammad; Irfan, Muhammad; Glowacz, Adam; Rahman, Saifur
    A compact tree shape planar quad element Multiple Input Multiple Output (MIMO) antenna bearing a wide bandwidth for 5G communication operating in the millimeter-wave spectrum is proposed. The radiating element of the proposed design contains four different arcs to achieve the wide bandwidth response. Each radiating element is backed by a 1.57 mm thicker Rogers-5880 substrate material, having a loss tangent and relative dielectric constant of 0.0009 and 2.2, respectively. The measured impedance bandwidth of the proposed quad element MIMO antenna system based on 10 dB criterion is from 23 GHz to 40 GHz with a port isolation of greater than 20 dB. The measured radiation patterns are presented at 28 GHz, 33 GHz and 38 GHz with a maximum total gain of 10.58, 8.87 and 11.45 dB, respectively. The high gain of the proposed antenna further helps to overcome the atmospheric attenuations faced by the higher frequencies. In addition, the measured total efficiency of the proposed MIMO antenna is observed above 70% for the millimeter wave frequencies. Furthermore, the MIMO key performance metrics such as Mean Effective Gain (MEG) and Envelope Correlation Coefficient (ECC) are analyzed and found to conform to the required standard of MEG < 3 dB and ECC < 0.5. A prototype of the proposed quad element MIMO antenna system is fabricated and measured. The experimental results validate the simulation design process conducted with Computer Simulation Technology (CST) software.
  • Küçük Resim
    Öğe
    Poloxamer-188 and d-?-tocopheryl polyethylene glycol succinate (TPGS-1000) mixed micelles integrated orodispersible sublingual films to improve oral bioavailability of ebastine in vitro and in vivo characterization
    (MDPI, 2021) Islam, Nayyer; Irfan, Muhammad; Khan, Salah-Ud-Din; Syed, Haroon Khalid; Iqbal, Muhammad Shahid; Khan, Ikram Ullah; Mahdy, Amina; Raafat, Mohamed; Hossain, Mohammad Akbar; Inam, Sana; Münir, Rabia; Ishtiaq, Memoona
    Orodispersible sublingual films (OSFs) composed of hydrophilic polymers were loaded with poloxamer-188 and d-alpha-tocopheryl polyethylene glycol succinate (TPGS-1000) mixed micelles to improve the oral bioavailability of a poorly soluble drug, ebastine (EBT). Mixed micelles formed by thin-film hydration method were incorporated into orodispersible sublingual film, consisting of HPMC and glycerol, using solvent casting technique. The mixed micelles and films were thoroughly evaluated for physicochemical characterization (size, polydispersity index, zeta potential, entrapment efficiency, thickness, weight, surface pH studies, disintegration time, swelling indices, mechanical properties, FTIR, PXRD, DSC, SEM, AFM, in vitro drug release, in vivo bioavailability, and toxicological studies). The results showed that the average particle size of mixed micelles was 73 nm. The mean zeta potential and PDI of the optimal mixed micelles formulation were -26 mV and 0.16, respectively. Furthermore, the maximum entrapment efficiency 82% was attained. The film's disintegration time was in the range of 28 to 102 s in aqueous media. The integrity of micelles was not affected upon incorporation in films. Importantly, the micelles-loaded films revealed rapid absorption, high permeability, and increased bioavailability of EBT as compared to the pure drug. The existence of ebastine loaded mixed micelles in the films enhanced the bioavailability about 2.18 folds as compared to pure drug. Further, the results evidently established in-vitro and in-vivo performance of bioavailability enhancement, biocompatibility, and good safety profile of micelles-loaded orodispersible EBT films. Finally, it was concluded that film loaded with poloxamer-188/TPGS-1000 mixed micelles could be an effective carrier system for enhancing the bioavailability of ebastine.