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Professor Zeeshan Ahmad

Job: Professor in Pharmaceutics and Drug Delivery and Royal Society Industry Fellow

Faculty: Health and Life Sciences

School/department: Leicester School of Pharmacy

Address: De Montfort, University, The Gateway, Leicester, LE1 9BH.

T: +44 (0)116 250 6455

E: zahmad@dmu.ac.uk

W: /pharmacy

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Personal profile

  • Pharmaceutics
  • Pharmaceutical Engineering and Technology
  • Drug Delivery
  • Nanotechnology
  • Nanoscience
  • Biomaterials
  • Formulation
  • Nanoparticles
  • Nanofibers
  • Microparticles
  • Pharmaceutical analysis (various models and delivery systems)

Prof. Zeeshan Ahmad's research is illustrated on the images to the right.

Zeeshan Ahmad is a Professor in Pharmaceutics and Drug Delivery & Royal Society Industry Fellow at 51Âþ»­ (School of Pharmacy). He is a Royal Society Industry Fellow and also leads the EPSRC EHDA Network (a highly interdisciplinary initiative involving industry and academia).

He has broad research interests in medical materials and their applications for healthcare (interfacing at chemistry, biology, physics and biomedical engineering).

Specifically, these include various methods of drug delivery (smart nanoparticles and microparticles, bubbles, fibrous materials and transdermal/skin contact systems), tissue engineering (scaffolds and cell guidance), medical device coatings (orthopedic implants) and biomedical material synthesis (polymers and bioceramics) and fabrication (EHDA, microfluidic and emulsion methods).

He has published numerous articles and is also a peer-reviewer for various journal publishers (RSC, Elsevier, Springer, ACS, IoP, etc). He has delivered presentations (national and international) at symposia (including conferences), industry and universities.He has supervised numerous PhD students (including to completion, national and international) in additon to undergraduates on MPharm, BSc Pharm Sci, BSc Pharm and Cosm Sci, MSc Biomaterials.  

Work (Research/Academic) History

  • Professor in Pharmaceutics and Drug Delivery, 51Âþ»­ (51Âþ»­)  - School of Pharmacy. August 2016 - present 
  • Reader (Associate Professor) in Pharmaceutics
    - School of Pharmacy
    August 2015 - July 2016
  • Senior Lecturer in Pharmaceutical Technologies
    - School of Pharmacy
    April 2013 - July 2015
  • Senior Lecturer in Pharmceutics
    - School of Pharmacy
    September 2010 - March 2013
  • Leverhulme Research Fellow May 2010 - August 2010
  • EPSRC Research Fellow
    January 2008- April 2010
  • Research Assistant (EPSRC)
    January 2006 - December 2007
  • Research Assistant (EPSRC)
    January 2005 - December 2005

Education

Research group affiliations

Pharmaceutical Technologies

Publications and outputs


  • dc.title: Development of hybrid 3D-printed structure with aligned drug-loaded fibres using in-situ custom designed templates dc.contributor.author: Muldoon, Kirsty; Feng, Yu; Dooher, Thomas; O'Connor, Caolan; Wang, Baolin; Wang, Hui-Min David; Ahmad, Z.; McLaughlin, James; Chang, Ming-Wei dc.description.abstract: Fibre alignment technology is crucial in various emerging applications, such as drug delivery systems, tissue engineering, and scaffold fabrication. However, conventional methods have limitations when it comes to incorporating aligned fibres into 3D printed structures in situ. This research demonstrates the use of custom-designed templates made with conductive ink to control the alignment of drug-loaded polymer fibres on a 3D printed microscale structure. Three different geometries were designed, and the effects of the template on fibre diameter and pattern were investigated. The hybrid structure demonstrated successful control of aligned fibres on printed structures using grounded conductive ink geometric electrodes, as confirmed by SEM. All three custom-designed templates presented unique geometric alignments and fibre diameters of around 1 μm. Additionally, the different collector shapes had an impact on the distribution of fibre diameters. FTIR and EDX analyses concluded that the drug was effectively encapsulated throughout the fibres. In-situ deposition of fibres onto the 3D printed structure enhanced the mechanical properties, and water contact angle results showed that the hybrid structure transitioned to a hydrophilic state with the addition of fibres. A drug delivery study confirmed that the hybrid structure functions as a steady release system, following a Korsmeyer-Peppas kinetic release model. TGA results indicated that the samples are thermally stable, and DSC analysis concluded that the samples were homogeneously produced. The results obtained from the hybrid structures provide a novel mechanism for integrating aligned fibres and 3D printed structures for development in fields such as biomedical engineering, regenerative medicine, and advanced manufacturing. dc.description: open access article

  • dc.title: Engineering of tetanus toxoid-loaded polymeric microneedle patches dc.contributor.author: Arshad, Muhammad Sohail; Gulfam, Shafaq; Zafar, Saman; Jalil, Najmusama Abdul; Ahmad, Nadia; Qutachi, Omar; Chang, Ming-Wei; Singh, Neenu; Ahmad, Z. dc.description.abstract: This study is aimed to fabricate tetanus toxoid laden microneedle patches by using a polymeric blend comprising of polyvinyl pyrrolidone and sodium carboxymethyl cellulose as base materials and sorbitol as a plasticizer. The tetanus toxoid was mixed with polymeric blend and patches were prepared by using vacuum micromolding technique. Microneedle patches were evaluated for physical attributes such as uniformity of thickness, folding endurance, and swelling profile. Morphological features were assessed by optical and scanning electron microscopy. In vitro performance of fabricated patches was studied by using bicinchoninic acid assay (BCA). Insertion ability of microstructures was studied in vitro on model skin parafilm and in vivo in albino rat. In vivo immunogenic activity of the formulation was assessed by recording immunoglobulin G (IgG) levels, interferon gamma (IFN-γ) levels, and T-cell (CD4+ and CD8+) count following the application of dosage forms. Prepared patches, displaying sharp-tipped and smooth-surfaced microstructures, remained intact after 350 ± 36 foldings. Optimized microneedle patch formulation showed ~ 74% swelling and ~ 85.6% vaccine release within an hour. The microneedles successfully pierced parafilm. Histological examination of microneedle-treated rat skin confirmed disruption of epidermis without damaging the underneath vasculature. A significant increase in IgG levels (~ 21%), IFN-γ levels (~ 30%), CD4+ (~ 41.5%), and CD8+ (~ 48.5%) cell count was observed in tetanus vaccine-loaded microneedle patches treated albino rats with respect to control (untreated) group at 42nd day of immunization. In conclusion, tetanus toxoid-loaded microneedle patches can be considered as an efficient choice for transdermal delivery of vaccine without inducing pain commonly experienced with hypodermic needles.

  • dc.title: Influence of Critical Parameters on Cytotoxicity Induced by Mesoporous Silica Nanoparticles dc.contributor.author: Amirsadra, Ahmadi; Sokunbi, Moses O.; Patel, Trisha; Ahmad, Z.; Singh, Neenu dc.description.abstract: Mesoporous Silica Nanoparticles (MSNs) have received increasing attention in biomedical applications due to their tuneable pore size, surface area, size, surface chemistry, and thermal stability. The biocompatibility of MSNs, although generally believed to be satisfactory, is unclear. Physicochemical properties of MSNs, such as diameter size, morphology, and surface charge, control their biological interactions and toxicity. Experimental conditions also play an essential role in influencing toxicological results. Therefore, the present study includes studies from the last five years to statistically analyse the effect of various physicochemical features on MSN-induced in-vitro cytotoxicity profiles. Due to non-normally distributed data and the presence of outliers, a Kruskal-Wallis H test was conducted on different physicochemical characteristics, including diameter sizes, zeta-potential measurements, and functionalisation of MSNs, based on the viability results, and statistical differences were obtained. Subsequently, pairwise comparisons were performed using Dunn's procedure with a Bonferroni correction for multiple comparisons. Other experimental parameters, such as type of cell line used, cell viability measurement assay, and incubation time, were also explored and analysed for statistically significant results. dc.description: open access article

  • dc.title: Electrohydrodynamic atomisation driven design and engineering of opportunistic particulate systems for applications in drug delivery, therapeutics and pharmaceutics dc.contributor.author: Zaman, Aliyah; Sayed, Elshaimaa; Evans, David; Morgan, Stuart; Samwell, Chris; Hall, John; Arshad, Muhammad Sohail; Qutachi, Omar; Chang, Ming-Wei; Ahmad, Z.; Simgh, Neenu; Ali, Amna dc.description.abstract: Electrohydrodynamic atomisation (EHDA) technologies have evolved significantly over the past decade; branching into several established and emerging healthcare remits through timely advances in the engineering sciences and tailored conceptual process designs. More specifically for pharmaceutical and drug delivery spheres, electrospraying (ES) has presented itself as a high value technique enabling a plethora of different particulate structures. However, when coupled with novel formulations (e.g. co-flows) and innovative device aspects (e.g., materials and dimensions), core characteristics of particulates are manipulated and engineered specifically to deliver an application driven need, which is currently lacking, ranging from imaging and targeted delivery to controlled release and sensing. This demonstrates the holistic nature of these emerging technologies; which is often overlooked. Parametric driven control during particle engineering via the ES method yields opportunistic properties when compared to conventional methods, albeit at ambient conditions (e.g., temperature and pressure), making this extremely valuable for sensitive biologics and molecules of interest. Furthermore, several processing (e.g., flow rate, applied voltage and working distance) and solution (e.g., polymer concentration, electrical conductivity and surface tension) parameters impact ES modes and greatly influence the production of resulting particles. The formation of a steady cone-jet and subsequent atomisation during ES fabricates particles demonstrating monodispersity (or near monodispersed), narrow particle size distributions and smooth or textured morphologies; all of which are successfully incorporated in a one-step process. By following a controlled ES regime, tailored particles with various intricate structures (hollow microspheres, nanocups, Janus and cell-mimicking nanoparticles) can also be engineered through process head modifications central to the ES technique (single-needle spraying, coaxial, multi-needle and needleless approaches). Thus, intricate formulation design, set-up and combinatorial engineering of the EHDA process delivers particulate structures with a multitude of applications in tissue engineering, theranostics, bioresponsive systems as well as drug dosage forms for specific delivery to diseased or target tissues. This advanced technology has great potential to be implemented commercially, particularly on the industrial scale for several unmet pharmaceutical and medical challenges and needs. This review focuses on key seminal developments, ending with future perspectives addressing obstacles that need to be addressed for future advancement. dc.description: The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.

  • dc.title: 3D Electrohydrodynamic Printing of Highly Aligned Dual-Core Graphene Composite Matrices dc.contributor.author: Ahmad, Z.; Wang, Baolin; Chen, Xing; Huang, Jie; Chang, Ming-Wei dc.description.abstract: The aim of this study was to develop an EHD printing method to fabricate graphene-loaded polycaprolactone (PCL)/polyethylene oxide (PEO) dual-core matrices. Graphene was incorporated in shell PCL components, while gelatin and dopamine hydrochloride (DAH) were encapsulated in two PEO cores to enhance biocompatibility of graphene-loaded matrices. Furthermore, the effect of PEO concentration on dual-core fiber formation was evaluated. The influence of process parameters (applied voltage, inner flow rate, outer flow rate and X-Y-Z collector stage speed) on dual-core fiber morphology was evaluated. Our findings show graphene-loaded structures to possess two inner cores and increasing graphene content yields matrices with smoother surfaces, causing a slight reduction in their contact angle behavior. Furthermore, the addition of graphene to matrices results in reduced elasticity. DAH release from matrices comprising various graphene concentrations showed no significant difference and drug release mechanism was diffusion based. In vitro biological tests indicate resulting graphene-loaded dual-core matrices exhibit good biocompatibility and also improve PC12 cell migration. The findings suggest matrices to have potential applications in nerve restoration and regeneration. dc.description: The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.

  • dc.title: Assessing the ex vivo permeation behaviour of functionalised contact lens coatings engineered using an electrohydrodynamic technique dc.contributor.author: Ahmad, Z.; Alany, Raid G.; Amoaku, W. M.; Chang, Ming-Wei; Alqahtani, Ali; Arshad, Muhammad Sohail; Qutachi, Omar; Al-Kinani, Ali A.; Mehta, P. dc.description.abstract: In vitro testing alone is no longer considered sufficient evidence presented solely with respect to drug release and permeation testing. These studies are thought to be more reliable and representative when using tissue or animal models; as opposed to synthetic membranes. The release of anti-glaucoma drug timolol from electrically atomised coatings was assessed here using freshly excised bovine corneal tissue. Electrohydrodynamic processing was utilised to engineer functionalised fibrous polyvinylpyrrolidone (PVP)-Poly (N-isopropylacrylamide) (PNIPAM) coatings or the outer side of commercial silicone contact lenses. Benzalkonium chloride (BAC), ethylenediaminetetraacetic acid (EDTA), Brij® 78 and borneol were employed as permeation enhancers to see their effect on ex vivo permeation of timolol maleate through the cornea. Formulations containing permeation enhancers showed a vast improvement with respect to cumulative amount of drug permeating through the cornea as shown by a 6 fold decrease in lag time compared to enhancer-free formulations. Most drug delivery systems require the drug to pass or permeate through a tissue or biological membrane. This study has shown that to fully appreciate and understand how a novel drug delivery system will behave not only within the device but with the external environment or tissue, it is imperative to have in vitro and ex vivo data in conjunction. dc.description: open access article

  • dc.title: Engineering and development of chitosan-based Nanocoatings for Ocular Contact Lenses dc.contributor.author: Mehta, P.; Al-Kinani, Ali A.; Arshad, Muhammad Sohail; Singh, Neenu; van der Merwe, Susanna M.; Chang, Ming-Wei; Alany, Raid G.; Ahmad, Z. dc.description.abstract: The research manuscript reports on Electrohydrodynamic Atomisation (EHDA) to engineer on-demand novel coatings for ocular contact lenses. A formulation approach was adopted to modulate the release of timolol maleate (TM) using chitosan and borneol. Polymers polyvinylpyrrolidone (PVP) and poly (N-isopropylacrylamide) (PNIPAM) were utilised to encapsulate TM and were electrically atomised to produce optimised, stationary contact lens coatings. The particle and fibre diameter, thermal stability, material compatibility of the formed coatings along with their in vitro release-modulating effect and ocular tolerability were investigated. The results demonstrated highly stable nano-matrices with advantageous morphology and size. All formulations yielded coatings with high TM encapsulation (>88%); with excellent ocular biocompatibility. The coatings presented biphasic and triphasic release profiles; depending on composition. Kinetic modelling revealed a noticeable effect of chitosan; the higher the concentration, the more the release of TM due to chitosan swelling; with the release mechanism changing from Fickian diffusion (1% w/v; n = 0.5) to non-Fickian (5% w/v, 0.45 < n < 0.89). The use of EHDA has not yet been explored in depth within the ocular research remit; engineering on demand lens coatings capable of sustaining TM release. This is likely to offer an alternative dosage form for management of glaucoma with particular emphasis on improving poor patient compliance. dc.description: The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.

  • dc.title: Pharmacological Effects of Natural Ganoderma and Its Extracts on Neurological Diseases: A Comprehensive Review dc.contributor.author: Zhao, C.; Zhang, Chunchen; Xing, Z.; Ahmad, Z.; Li, Jing-Song; Chang, Ming-Wei dc.description.abstract: Ganoderma, has been used for clinical applications for thousands of years as a highly-nutritious and significantly-effective medicinal herb. The active components and efficacy of Ganoderma are constantly being explored and supplemented every year. In recent years, more and more literature has reported the pharmacological effects of Ganoderma on anti-tumor, liver protection and immunity enhancement, especially on neuroprotection. Numerous research works on the neuroprotective effects of Ganoderma have been documented (e.g., modulation of neurogenesis, amelioration of Alzheimer's disease, therapeutic effect on epilepsy, the protective effect on neural cells in stroke injury, etc.) thus it has drawn increasing attention. However, an integrated and comprehensive review of recent research findings has not been detailed in any great depth. Therefore, the purpose of this review is to summarize and elucidate recent progress of neuroprotective effects of natural Ganoderma and its extracts. dc.description: The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.

  • dc.title: Dual Rotation Centrifugal Electrospinning: A Novel Approach to Engineer Multi-Directional and Layered Fiber Composite Matrices dc.contributor.author: Wang, Li; Wang, Baolin; Ahmad, Z.; Li, Jing-Song; Chang, Ming-Wei dc.description.abstract: In this study, a dual rotation centrifugal electrospinning system (DRCES) is designed, developed and used to prepare medicated fabrics. Through simultaneous rotation of both spinneret and collector; multi-directional blended fiber matrices (PVP and TPU) were deposited directly on the rotating collector. To detail the process, key stages of the centrifugal electrospinning process are elaborated, and the influence of gas infusion and collector rotation speed on resulting fiber morphologies were explored. Multi-directional fibrous structures show in vitro biocompatibility (fibroblast). Regulation of drug release rate was achieved using polymer composition and filament alignment. This study demonstrates a rapid fabrication method (~ 50 g/h) to engineer layered fibrous structures using DRCES; which provides a foundation for preparing complex drug matrices (single and multi–directional) for tailored active component release.

  • dc.title: Broad Scale & Structure Fabrication of Healthcare Materials for Drug and Emerging Therapies Via Electrohydrodynamic Techniques dc.contributor.author: Mehta, P.; Zaman, A.; Smith, A.; Rasekh, M.; Haj-Ahmad, R.; Arshad, M. S.; van der Merwe, S.; Chang, M-W.; Ahmad, Z. dc.description.abstract: The engineering of advanced healthcare materials provides a platform to address challenges facing interdisciplinary scientists, clinicians, pharmacists, biomaterial scientists and biomedical engineers. Niche and timely developments arising from the synthesis or extraction of more biocompatible materials, new biologically active components, clearer insights into disease mechanisms and novel therapies or strategies provide several timely opportunities. These include enhanced therapies with greater patient compliance, improved disease targeting, better diagnosis and bespoke medications for individuals. Electrohydrodynamic atomisation (EHDA) engineering comprises several processes making use of electric fields (e.g. through an applied voltage) interplaying with several forces (e.g. gravity and surface tension). Coupled to advanced materials (e.g. formulated media) and specifically configured apparatuses (e.g. nozzles, collectors and downstream processes); effective and controlled fabrication of various structures (fibers, particles, bubbles, grids, droplets) on various scales (macro, micro and nano) possessing various dimensions (2D, 3D and 4D) is readily achieved. The processes have distinct advantages compared to established engineering methods (ambient environment engineering, low shear, scalability, compartmentalisation etc.). This detailed review focuses on key concepts and developments in EHDA engineering pertaining to underlying principles, enabling tools and engineered structures specifically for healthcare remits. From initial experiments involving the behaviour of non-formulated liquids on charged amber to recent developments in complex 3D matrix printing; the EHDA route has progressed significantly, most rapidly in the last two decades, and is capable of providing timely platform opportunities to tackle several global healthcare challenges dc.description: The file attached to this record is the author's final peer reviewed version.

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Key research outputs

  • Preparation and characterization of electrospun hydroxyapatite/poly-ε-carpolactone fibres loaded with ibuprofen and indomethacin
  • C. Karavasili et al. Biomedical Materials Research Part A. 102, 2583 (2014)
  • Continuous Generation of Ethyl Cellulose Drug Delivery Nanocarriers from Microbubbles
  • O.Gunduz et al. Pharmaceutical Research 30, 225 (2013)
  • Bioinspired bubble design for particle generation
  • O.Gunduz et al. Journal of the Royal Society Interface 9, 389 (2012)
  • Fabrication of biomaterials via controlled protein bubble generation and manipulation
  • Z. Ekemen et al. Biomacromolecules 12, 4291 (2011)
  • Nano-particle functionality and toxicity on the central nervous system
  • Z Yang et al. Journal of the Royal Society Interface 7, 411 (2010)
  • Novel preparation of transdermal drug-delivery patches and functional wound healing materials
  • Z. Ahmad et al. Journal of Drug Targeting 17, 724 (2009)
  • The role of electrosprayed nanoapatites in guiding osteoblast behaviour. E.S. Thian et al. Biomaterials 29, 1833 (2008)

Research interests/expertise

  • Pharmaceutics / Pharmaceutical Technologies
  • Pharmaceutic Dosage Design
  • Nanoparticles and Microparticles
  • Biomaterials (bioceramics and biocompatible polymers)
  • Biomedical Materials (applications for advanced functional biomaterials)
  • Drug Delivery Systems (transdermal (parenteral) and enteral systems)
  • Drug Delivery Systems (nano, micro and bubble)
  • Drug Delivery Systems (in-vitro models)
  • Drug Delivery Systems with Imaging modalities
  • Drug Delivery Technologies (EHDA, microfluidic, emulsions)
  • Bio and Tissue Engineering (scaffold design and cell guidance)
  • Implants (Coatings and Biocompatible materials)
  • Materials Chemistry (polymers/bioceramics and interfaces)
  • Biointerfaces (Cell guidance, Drug delivery systems at interfaces)
  • Material Fabrication (EHDA, Microfluidic, Emulsions, Casting).
  • Material Analysis: Optical, SEM, TEM, AFM, XRD, DSC, TGA, HPLC, UV, Confocal, FTIR, Raman, Terahertz. Physical properties of materials.

Areas of teaching

  • Product Formulation (lectures) (Yr2)
  • Development and Manufacture of Pharmaceutical Products (lectures) (Yr3)
  • New Approaches to Drug Delivery (lectures) (Yr3)
  • Product Formulation Labs (Yr2)
  • Compounding Labs (Yr1)
  • Final Year Project Supervision (Yr3)
  • MSc QbD Projects (MSc)

Qualifications

  • Doctor of Philosophy (PhD), Biomedical Materials
  • Bachelor of Science (BSc Hons), Pharmaceutical Chemistry
  • All other education in London, UK

Courses taught

  • Pharmaceutical and Cosmetic Sciences BSc

Honours and awards

Royal Society Industry Fellow

Leverhulme Research Fellow

Membership of professional associations and societies

  • American Chemical Society (ACS) - Member
  • Royal Society of Chemistry (RSC) - Member
  • Controlled Release Society (CRS) - Member
  • Controlled Release Society - UK Chapter (UKICRS) - Member
  • Academy of Pharmaceutical Sciences GB (APSGB) - Member
  • European Society of Biomaterials (ESB) - Member
  • UK Society of Biomaterials (UKSB) – Member

Current research students

Post-doctoral researchers:

  • Dr. R Haj-Ahmad
  • Dr.  M Rasekh (Visiting)

Past PhD students (completed) -

  • Z Ekemen (Co-I)
  • M Rasekh (Co-I)
  • O Gunduz (Co-I)
  • A Smith (P-I/Co-I)
  • I Kucuc (Co-I)

Current PhD students -

  • K Nazari
  • P Mehta
  • A Gamal
  • S Ramzan
  • A Al-Asiri

Externally funded research grants information

 

  • RCUK (EPSRC), Royal Society, EU and Industry

 

Professional esteem indicators

  • Peer reviewer for numerous internationally recognised journals (mainly from Springer, Wiley, RSC, Elsevier, IoP, ASPB, Informa, PLoS)
 

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