Muhsincan Sesen

Imperial College London | Imperial · Department of Bioengineering

Chronic wounds don't spontaneously heal and heavily affect patients’ quality of life. Current scaffolds are expensive structures that only passively support wound regeneration. Cell-based scaffolds are potential alternatives, but cell-associated risks and costly ex vivo fabrication are hindering their translation. We are developing a handheld print...

Natural Polymer-Based Bioinks for In Situ Bioprinting

Handheld Bioprinting of Bioorthogonally Crosslinked Hydrogels .

Pharma 4.0 is the exciting implementation of Industry 4.0 for pharmaceutical manufacturing. This chapter starts with the discussion of the regulatory driving forces for the pharmaceutical industry to embrace Pharma 4.0, especially the “Pharmaceutical Quality for the 21st Century—A Risk‐Based Approach” initiative, and Knowledge‐aided Assessment and...

Microfluidics has enabled low volume biochemistry reactions to be carried out at the point-of-care. A key component in microfluidics is the microfluidic valve. Microfluidic valves are not only useful for directing flow at intersections but also allow mixtures/dilutions to be tuned real-time and even provide peristaltic pumping capabilities. In the...

The development of protocols for bio/chemical reaction requires alternate dispensing and mixing steps. Whilst most microfluidic systems use the opening of additional parts of the channel to allow the ingress of fixed volumes of fluid, this requires knowledge of the protocol before the design of the chip. Our approach of using a microfluidic valve t...

The recent boom in single-cell omics has brought researchers one step closer to understanding the biological mechanisms associated with cell heterogeneity. Rare cells that have historically been obscured by bulk measurement techniques are being studied by single cell analysis and providing valuable insight into cell function. To support this progre...

Correction for ‘Comparison of bulk and microfluidic methods to monitor the phase behaviour of nanoparticles during digestion of lipid-based drug formulations using in situ X-ray scattering’ by Ben J. Boyd et al. , Soft Matter , 2019, 15 , 9565–9578.

The performance of orally administered lipid-based drug formulations is crucially dependent on digestion, and understanding the colloidal structures formed during digestion is necessary for rational formulation design. Previous studies using the established bulk pH-stat approach (Hong et al. 2015), coupled to synchrotron small angle X-ray scatterin...

The top candidate for further miniaturisation of high throughput screening is droplet microfluidics. The presented study investigates one of the important manipulation techniques of droplet microfluidics, droplet splitting; utilising a novel single-layer valve, we improve selectivity and response time of the splitting technique. Flexibility of PDMS...

A novel, on-demand microfluidic droplet merging mechanism is presented in this paper. We demonstrate that a narrow beam surface acoustic wave (SAW), targeted at the oil buffer, causes nearby droplets to coalesce. The lack of direct exposure of the droplet to the excitation stimulus makes this method ideal for sensitive samples as harm will not occu...

The transition from micro well plate and robotics based high throughput screening (HTS) to chip based screening has already started. This transition promises reduced droplet volumes thereby decreasing the amount of fluids used in these studies. Moreover, it significantly boosts throughput allowing screening to keep pace with the overwhelming number o...

Mono-disperse droplet formation in microfluidic devices allows the rapid production of thousands of identical droplets and has enabled a wide range of chemical and biological studies through repeat tests performed at pico-to-nanoliter volume samples. However, it is exactly this efficiency of production which has hindered the ability to carefully co...

Acoustic forces have been widely used to control microparticles within microfluidic systems. Such acoustofluidic systems have been very successful in tasks such as cell sorting, however, to date efforts have been mostly limited to single phase systems. Just as the contrast in acoustic impedance between a fluid and suspended particle means that acou...

A popular approach to monitoring diseases and their diagnosis is through biological, pathological or immunological characterization. However, at a cellular level progression of certain diseases manifests itself through mechanical effects as well. Here, we present a method which exploits localised flow; surface acoustic wave (SAW) induced acoustic s...

This study presents a novel acoustic mixer comprising of a microfabricated silicon nitride membrane with a hole etched through it. We show that the introduction of the through hole leads to extremely fast and homogeneous mixing. When the membrane is immersed in fluid and subjected to acoustic excitation, a strong streaming field in the form of vort...

Digital microfluidic systems, in which isolated droplets are dispersed in a carrier medium, offer a method to study biological assays and chemical reactions highly efficiently. However, it's challenging to manipulate these droplets in closed microchannel devices. Here, we present a method to selectively steer plugs (droplets with diameters larger t...

In this study, we present a method for fine focusing of microparticles using a vibrating air bubble. Fluorescent polystyrene particles of 2.01 and 6.60 μm are shown to be focused along the edge of a 50-μm-wide channel. The mechanism is determined to be shear stresses caused by the boundary layer on the vibrating gas/liquid meniscus. Experiments sho...

This letter presents a method which employs surface acoustic wave induced acoustic streaming to differentially peel treated red blood cells (RBCs) off a substrate based on their adhesive properties and separate populations of pathological cells from normal ones. We demonstrate the principle of operation by comparing the applied power and time requi...

Individual droplets can be isolated within microfluidic systems by use of an immiscible carrier layer. This type of two phase systems, often termed "digital microfluidics", find wide ranging applications in chemical synthesis and analysis. To conduct on-chip biochemical analysis, a key step is to be able to merge droplets selectively in order to in...

Hydrodynamic cavitation is a physical phenomenon characterized by vaporization and bubble formation in liquids under low local pressures, and their implosion following their release to a higher pressure environment. Collapse of the bubbles releases high energy and may cause damage to exposed surfaces. We recently designed a set-up to exploit the de...

Sub-cooled flow boiling was investigated over nanostructured plate (of dimensions 20mm×20mm) integrated to a rectangular channel (of dimensions 33mm×9mm×33mm) at flow rates ranging from 69 ml/min to 145 ml/min. The configuration of the nanostructured plate includes ∼600 nm long copper nanorod arrays with an average nanorod diameter of ∼150 nm. The...

Nanofluids offer a potential breakthrough as next-generation heat transfer fluids since they offer exciting new possibilities to enhance heat transfer performance compared to pure liquids. A major drawback for using nanofluids in practical applications is difficulty in maintaining their stability due to deposition on surfaces. In this study, we pro...

In this paper, the results of a series of heat transfer experiments conducted on a compact electronics cooling device based on single and two phase jet impingement technique are reported. Deionized and degassed water is propelled into four microchannels. The generated jet impingement is targeted through these channels towards the surface of two nan...

In this study, we have experimentally demonstrated that heat transfer can be substantially increased by actuating magnetic nanoparticles inside a nanofluid. In order to materialize this, we have utilized a miniature heat transfer enhancement system based on the actuation of magnetic nanoparticles dispersed in a base fluid (water). This compact syst...

In this initial study, the effect of hydrodynamic flow on lysozyme structure and function was investigated using a microchannel device. Protein was subjected to bubbly cavitation as well as noncavitating flow conditions at pH 4.8 and 25 °C. Interestingly, time course analyses indicated that the secondary structure content, the hydrodynamic diameter...

An experimental setup is designed to simulate the heat dissipated by electronic devices and to test the effects of nanostructured plates in enhancing the heat removal performance of jet impingement systems in such cooling applications under boiling conditions. Prior experiments conducted in single phase have shown that such different surface morpho...

Magnetic nanoparticle suspensions and their manipulation are becoming an alternative research line. They have vital applications in the field of microfluidics such as microscale flow control in microfluidic circuits, actuation of fluids in microscale, and drug delivery mechanisms. In microscale, it is possible and beneficial to use magnetic fields...

The objective of this study is to reveal the potential of micro scale hydrodynamic bubbly cavitation for the use of kidney stone treatment. Hydrodynamically generated cavitating bubbles were targeted to the surfaces of 18 kidney stone samples made of calcium oxalate, and their destructive effects were exploited in order to remove kidney stones in i...

Magnetic actuation of ferrofluids is an emergent field that will open up new possibilities in various fields of engineering. The quality and topology of the magnetic field that is being utilized in such systems is determinant in terms of flow properties, flow rates and overall efficiency. Determining the optimal magnetic field topology to achieve t...

Magnetic nanoparticle suspensions and their manipulation are becoming an alternative research line and have very important applications in the field of microfluidics such as microscale flow control in microfluidic circuits, actuation of fluids in microscale, and drug delivery mechanisms. In microscale, it is possible and beneficial to use magnetic...

An improvement in the current methods of ferrofluid actuation was presented in this paper. A novel magnetomechanical microfluidic pump design was implemented with a ferrofluid as the active working fluid. Obtained flow rates were comparable to previous results in this research line. It was also seen that the basic pump architecture, which the subje...

This paper presents a study that investigates the destructive energy output resulting from hydrodynamic bubbly cavitation in microchannels and its potential use in biomedical applications. The research performed in this study includes results from bubbly cavitation experiments and findings showing the destructive effects of bubbly cavitating flow o...

In this paper, the results of a series of heat transfer experiments conducted on a compact electronics cooling device based on single phase jet impingement techniques are reported. Deionized-water is propelled into four microchannels of inner d�ameter 685μm wh�ch are used as nozzles andl ocated at a nozzle to surface distance of 2.5mm. The generate...

An efficient cooling system without any external energy consumption that consists of a plate, on which an array of copper nanorods with an average diameter ~100 nm and length ~500 nm is integrated to a planar copper thin film coated silicon wafer surface, a heater, an aluminium base and a pool was developed. Heat is efficiently transferred from the...

This paper reports a compact nanostructure based heat sink. The system has an inlet and an outlet valve similar to a conventional heat sink. From the inlet valve, pressurized deionized-water is propelled into a rectangular channel (of dimensions 24mmx59mmx8mm). This rectangular channel houses a nanostructured plate, on which ~600 nm long copper nan...

Electromagnetically actuated microflows are generated by using ferromagnetic nanofluids containing Fe2 O3 based nanoparticles. Because of their magnetic properties these nanoparticles are able to response to a magnetic field imposed along a microchannel so that a microflow could be driven. Nanofluid samples were located inside a minichannel and wer...