Subrayal M Reddy

Subrayal M Reddy
University of Central Lancashire | UCLAN · Division of Chemistry

BSc PhD FRSC FHEA

About

73
Publications
4,921
Reads
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1,578
Citations
Additional affiliations
January 2018 - present
University of Central Lancashire
Position
  • Professor (Full)
Description
  • Professor of Biomaterials and Analytical Chemistry
October 2016 - December 2016
University of Central Lancashire
Position
  • Reader (Associate Professor) Analytical Chemistry
April 2009 - present
University of Surrey
Position
  • Senior Lecturer Applied Analytical Chemistry
Description
  • Teach at BSc and MSc at all levels in Analytical and Physical Chemistry modules.
Education
October 1991 - September 1994
The University of Manchester
Field of study
  • Smart Materials and Biosensors
October 1987 - July 1990
The University of Manchester
Field of study
  • Chemistry

Publications

Publications (73)
Article
Full-text available
We report the investigation of electropolymerised molecularly imprinted polymers (E-MIPs) for the determination of dioctyl phthalate (DOP). Low-cost and eco-friendly commercially available screen-printed electrodes (SPEs) were used. E-MIPs were produced using the cyclic voltammetry (CV) technique based on a water-soluble 4-aminophenol as functional...
Article
Molecularly imprinted polymers (MIPs) are fast becoming alternatives to biological recognition materials, offering robustness and the ability to work in extreme environments. Here, a modified thymine-based nucleobase, with acrylamide at the 5-postion (AA-dT) was used as a co-monomer in the synthesis of a thin-film electropolymerised MIP system for...
Article
Full-text available
In conjunction with polyacrylamide gel electrophoresis (PAGE), molecular imprinting methods have been applied to produce a multilayer mini‐slab in order to evaluate how selectively and specifically a hydrogel‐based molecularly imprinted polymer (MIP) binds bovine haemoglobin (BHb, ~64.5 kDa). A three‐layer mini‐slab comprising an upper and lower la...
Article
Aurein 2.1, aurein 2.6 and aurein 3.1 are amphibian host defence peptides that kill bacteria via the use of lytic amphiphilic α-helical structures. The C-terminal PEGylation of these peptides led to decreased antibacterial activity (Minimum Lethal Concentration (MLCs) ↓ circa one and a half to threefold), reduced levels of amphiphilic α-helical str...
Article
Full-text available
We evaluate a series of thin-sheet hydrogel molecularly imprinted polymers (MIPs), using a family of acrylamide-based monomers, selective for the target protein myoglobin (Mb). The simple production of the thin-sheet MIP offers an alternative biorecognition surface that is robust, stable and uniform, and has the potential to be adapted for biosenso...
Article
Full-text available
We have developed a low-cost molecularly imprinted polymer (MIP)-based fluorometric assay to directly quantify myoglobin in a biological sample. The assay uses a previously unreported method for the development of microwave-assisted rapid synthesis of aldehyde functionalized magnetic nanoparticles, in just 20 minutes. The aldehyde functionalized na...
Article
Molecularly imprinted polymers (MIPs) have the potential to become alternatives to antibodies in the diagnosis and treatment of disease. However, atomistic level knowledge of the prepolymerization process is currently limited that would facilitate the rational design of more efficient MIPs. Towards this goal, we have investigated using computation...
Article
Full-text available
Rapid development of antibody-based therapeutics are crucial to the agenda of innovative manufacturing of macromolecular therapies to combat emergent diseases. Although highly specific, antibody therapies are costly to produce. Molecularly imprinted polymers (MIPs) constitute a rapidly-evolving class of antigen-recognition materials that act as syn...
Article
Full-text available
Whilst the profiling of the transcriptome and proteome even of single-cells becomes feasible, the analysis of the translatome, which refers to all messenger RNAs (mRNAs) engaged with ribosomes for protein synthesis, is still an elaborate procedure requiring millions of cells. Herein, we report the generation and use of “smart materials”, namely mol...
Poster
Full-text available
A new class of nucleants has emerged with the discovery that porous materials with a distribution of pore sizes similar to those of protein molecules are effective for inducing protein crystals. Building on the success of such porous materials, we sought to design nucleants with improved specificity for protein molecules while maintaining the idea...
Chapter
Membranes are ubiquitous in life encapsulating and regulating the content of all cells and have pervaded society, from large-scale industrial such as seawater desalination to medical applications such as haemodialysis.
Chapter
Since the advent of smartphone technologies, the word “sensor” has become more and more commonplace outside of the academic environment. Nowadays, it is easy to find smartphones with a variety of sensors, for example, proximity, motion, ambient light, gyroscopic, and magnetic. These sensors are devices that detect inputs from the physical environme...
Article
Full-text available
Due to recent public concern and interest in the authenticity and origin of meat, for example, the 2013 “horsemeat scandal” in the human food chain, novel sensor strategies for the discrimination between protein species are highly sought after. In this work, molecularly imprinted polymers (MIPs) are utilised for protein discrimination using electro...
Article
Full-text available
Polyacrylamide hydrogel entrapment of EuD 4 TEA or Cu(NCS)(py) 2 (PPh 3) radically extends the emission time of the triboluminescent (TL) crystalline particles by a factor of 10 3 , optimized when matching the hydrophilic/ hydrophobic characteristics of the TL/gel components. Triboluminescence intensity improves with hydration of the TL/hydrogel co...
Article
The accurate determination of intact macromolecules in biological samples, such as blood, plasma, serum, urine, tissue and feces is a challenging problem. The increased interest in macromolecules both as candidate drugs and as biomarkers for diagnostic purposes means that new method development approaches are needed. This review charts developments...
Book
This book covers new materials used as analytical devices for increasing the interactions between the development of new analytical devices and materials science. The authors describe how different types of materials such as polymers, self-assembled layers, phthalocyanines, and nanomaterials can further enhance sensitivity and promote selectivity b...
Article
We report the use of a colorimetric plastic-based device to discriminate four pathogenic bacteria: Klebsiella pneumoniae, Proteus vulgaris, Proteus mirabilis and Escherichia coli. The colour changes of the plastic membranes were analysed with RGB values extracted from dye-integrated polymeric membrane images obtained with a smartphone and used as i...
Article
Full-text available
Unlabelled: We report the fabrication of metal-coded molecularly imprinted polymers (MIPs) using hydrogel-based protein imprinting techniques. A Co(II) complex was prepared using (E)-2-((2 hydrazide-(4-vinylbenzyl)hydrazono)methyl)phenol; along with iron(III) chloroprotoporphyrin (Hemin), vinylferrocene (VFc), zinc(II) protoporphyrin (ZnPP) and pr...
Article
Full-text available
The fabrication and validation of the first semi-liquid nonprotein nucleating agent to be administered automatically to crystallization trials is reported. This research builds upon prior demonstration of the suitability of molecularly imprinted polymers (MIPs; known as `smart materials') for inducing protein crystal growth. Modified MIPs of altere...
Article
Full-text available
Amine-based volatile compounds released by microorganisms offer an alternative diagnostic approach for the identification of foodborne pathogens. Our objective has been to solvent cast cellulose acetate membranes to immobilise dyes and to use the resultant membranes as a plastic device to discriminate between different types of amines (triethylamin...
Article
We have studied acrylamide-based polymers of varying hydrophobicity (acrylamide, AA; N-hydroxymethylacrylamide, NHMA; N-isopropylacrylamide, NiPAm) for their capability of imprinting protein. Rebinding capacities (Q) from spectroscopic studies were highest for bovine haemoglobin (BHb) MIPs based on AA, Q = 4.8 ± 0.21 < NHMA, Q = 4.3 ± 0.32 < NiPAm,...
Article
We present the development of an electrochemical biosensor based on modified glassy carbon (GC) electrodes using hydrogel-based molecularly imprinted polymers (MIPs) has been fabricated for protein detection. The coupling of pattern recognition techniques via principal component analysis (PCA) has resulted in unique protein fingerprints for corresp...
Chapter
Molecularly imprinted polymers (MIPs) have become an important tool in the preparation of artificial and robust recognition materials that are capable of mimicking natural systems. MIPs have been regarded as 'antibody mimics' and have shown clear advantages over real antibodies for sensor technology. Currently, on-site diagnostic (OSD) and point-of...
Article
Full-text available
Hydrogel-based molecularly imprinted polymers (HydroMIPs) were prepared for several proteins (haemoglobin, myoglobin and catalase) using a family of acrylamide-based monomers. Protein affinity towards the HydroMIPs was investigated under equilibrium conditions and over a range of concentrations using specific binding with Hill slope saturation prof...
Article
We have investigated the effect of buffer solution composition and pH during the preparation, washing and re-loading phases within a family of acrylamide-based molecularly imprinted polymers (MIPs) for bovine haemoglobin (BHb), equine myoglobin (EMb) and bovine catalyse (BCat). We investigated water, phosphate buffer saline (PBS), tris(hydroxymethy...
Article
A polyacrylamide-based molecularly imprinted polymer (MIP) was prepared for bovine haemoglobin (BHb). A 3 mg/ml solution of BHb was injected over a dual polarisation interferometer (DPI) sensor to form a physisorbed layer typically of 3.5 ± 0.5 nm thickness. Onto the pre-adsorbed protein layer, MIP and NIP (non-imprinted polymer) were separately in...
Article
We have characterised the imprinting capability of a family of acrylamide polymer-based molecularly imprinted polymers (MIPs) for 3 proteins using spectrophotometric and quartz crystal microbalance (QCM) sensor techniques. Bulk gel characterisation on acrylamide (AA), N-hydroxymethylacrylamide (NHMA) and N-isopropylacrylamide (NiPAM) gave varied se...
Article
An electrochemical method has been developed for the probing of hydrogel-based molecularly imprinted polymers (HydroMIPs) on the surface of a glassy carbon electrode. HydroMIPs designed for bovine haemoglobin selectivity were electrochemically characterised and their rebinding properties were monitored using cyclic voltammetry. The electrochemical...
Article
Full-text available
We present a previously undescribed initiative and its application, namely the design of molecularly imprinted polymers (MIPs) for producing protein crystals that are essential for determining high-resolution 3D structures of proteins. MIPs, also referred to as "smart materials," are made to contain cavities capable of rebinding protein; thus the f...
Article
We developed a novel method of fabricating polymer film on a substrate at atmospheric pressure using atmospheric-pressure plasma polymerization (APPP) with a laboratory-made torch-type APPP apparatus. We used allylamine and acrylic acid as model monomers to optimize the polymerization conditions and evaluate the fabricated films. The APPP films wer...
Article
There is a trend in biohazard diagnostics to develop integrated systems to extract, concentration and detection from sample matrices. Although biological recognition agents, such as antibodies, can be applied for concentration and detection, there are several limitations. Specifically, biological recognition agents are hard to produce in large quan...
Article
Full-text available
We report the transmission electron microscopy (TEM) imaging of a hydrogel based molecularly imprinted polymer (HydroMIP) specific to the template molecule bovine haemoglobin (BHb). A novel critical point drying based sample preparation technique was employed to prepare the molecularly imprinted polymer (MIP) samples in a manner that would facilita...
Article
A factor limiting the detection time of biological particles using a quartz crystal microbalance (QCM) system is the kinetics of the particles arriving within the sensing region of the crystal surface. A device has been developed which, for the first time, combines ac electro-kinetic particle manipulation with simultaneous acoustic sensing on an el...
Article
We developed a novel fabrication method of on-demand polymer film synthesis onto a substrate under atmospheric pressure using microplasma polymerization with a laboratory-made torch-type microplasma polymerization apparatus. We used styrene as model monomer for selection of polymerization condition of microplasma-polymerization and evaluation of mi...
Article
A surface plasmon resonance (SPR)-immunosensor for detection of the low molecular weight compound 2,4-dinitorophenol (DNP) at ultra-low concentration has been developed. The sensor strategy is based on a competitive immunoreaction between DNP and a DNP-protein conjugate, namely DNP-bovine serum albumin conjugate (DNP-BSA). Anti-DNP monoclonal antib...
Article
We have employed FITC--albumin as the protein template molecule in an aqueous phase molecular imprinted polymer (HydroMIP) strategy. For the first time, the use of a fluorescently labeled template is reported, with subsequent characterization of the smart material to show that the HydroMIP possesses a significant molecular memory in comparison to t...
Article
We have developed a strategy to produce molecularly imprinted polymers based on polyacrylamide hydrogels for the selective imprinting of bovine haemoglobin (BHb). For the first time, we have explored in detail a variety of template removal strategies including varying ratios of sodium dodecylsulphate:acetic acid (SDS:AcOH) and also the use of a try...
Article
We have characterised a range of modified poly(vinyl chloride) (PVC) membranes based on their permeability and selectivity to electrochemically active species. The species are detected at an amperometric (two-electrode) cell in phosphate buffer solution. Diffusants studied were paracetamol, catechol, ascorbic acid and hydrogen peroxide. Membrane mo...
Article
We have used the AT-cut quartz crystal sensor to measure in real-time the total cholesterol concentration in buffer and serum, using the trienzyme system of cholesterol esterase (ChE), cholesterol oxidase (ChOx) and horseradish peroxidase (HRP). The hydrogen peroxide produced from the ChE–ChOx reaction oxidises diaminobenzidine (DAB), in the presen...
Conference Paper
It was developed a conventional immunosensor for fibrinogen and fibrin degradation products (FDP) to combine a quartz crystal microbalance (QCM) with the agglutination reaction of immunized latex beads. We successfully measured FDP concentration of in human serum within 10 min by QCM method. The detection range of QCM immunosensor is covered with s...
Article
The benzidines, 3,3'-diaminobenzidine (DAB), 3,3'-dimethoxybenzidine (DMOB) and 3,3',5,5'-tetramethylbenzidine (TMB) were enzymatically oxidised to detect hydrogen peroxide, using the quartz crystal. The oxidised product mainly remains in suspension, resulting in a limited quartz sensor signal. We have used two non-ionic surfactants, Tween 80 and T...
Article
We have developed a quartz crystal microbalance (QCM) biosensor for the determination of organophosphorus and carbamate pesticides. A change in resonant frequency is observed as a result of mass adsorption, and we have used this as the basis for sensor development. Specifically, we have used a two-enzyme system (acetylcholine-esterase and choline o...
Article
We have used solvent casting techniques to immobilise glucose oxidase (GOD) within unplasticised and plasticised poly(vinyl chloride) (PVC) matrices. The plasticisers studied were the cationic surfactant, tricaprylmethylammonium chloride (Aliquat 336s), the anionic surfactant bis(2-ethylhexyl) hydrogenphosphate (BEP) and the lipid, isopropylmyrista...
Article
In this paper we report a method for the determination of 4-aminophenol (4-AP) in solution using a quartz crystal microbalance (QCM) sensor. 4-AP reacts with (para-unsubstituted) phenols to form hydrophobic indophenol dye species that precipitate out and adsorb to the surface of the crystal to produce a shift in the crystal resonant frequency. This...
Conference Paper
We describe a novel method for the determination of paracetamol, in solution, using a method of analyte-specific precipitation. Surface adsorption is detected using the quartz crystal microbalance (QCM) sensor. The method is based on the enzymatic hydrolysis of paracetamol using arylacylamidase (AAA) to give 4-aminophenol (4-AP). The 4-AP specifica...
Article
The AT-cut quartz crystal, operating in the thickness shear mode, has been used to detect 4-aminophenol. The mechanism of response involves a specific reaction with o-cresol to produce a hydrophobic indophenol dye that precipitates out and adsorbs to the quartz surface. Adsorption specificity for the crystal surface is enhanced via the pretreatment...
Article
This paper describes a method of clearly distinguishing the headspace response of water from selected organic compounds. By using hydrophobic unplasticised poly(vinyl chloride) (PVC) as an overlayer, we have been able to minimise water interference at a pre-formed conducting polymer sensor array. As well as attenuating the signal to water, the resp...
Article
Unplasticized polyvinyl chloride (PVC) has proved an especially difficult membrane material to form reproducibly. In its fabrication for sensor use, variable temperature solvent casting has been assessed and related to function as external membranes of a classical dual membrane amperometric oxidase electrode. The thermal history of the casting solu...
Article
A glucose biosensor has been developed which combines the substrate specificity offered by the enzyme glucose oxidase with the high sensitivity of a quartz crystal thickness-shear-mode sensor. Glucose is detected via the enzyme-catalysed formation of insoluble films of oxidised o-dianisidine on the crystal surface. Glucose levels can be measured in...
Article
It is demonstrated that an AT-cut quartz crystal driven in the thickness-shear-wave mode and typically used as a sensor to monitor the viscoelastic shear-wave properties of a fluid also produce longitudinal pressure waves. Unlike the shear wave, these waves are capable of long-range propagation through the fluid and of reflection at its boundaries,...
Chapter
Chemical sensors are ideally suited to miniaturisation and reformatting in order to conform to particular types of flowing, static and low volume samples. An important additional need is the complementary tailoring of a measurement cell in order to create a functional, integrated sensor-based measuring system. In this context the importance of samp...
Article
Ion selective and amperometric electrodes based on PVC membranes were constructed for the measurement of phenolics and assessed for potential use in monitoring coke works effluent treatment. Potentiometric working ranges are restricted to >100 mM, suffering thiocyanate interference, despite response slopes of <160mV/decade. Fabrication of a planar...
Article
A functionally haemocompatible lactate enzyme electrode system with an extended linear range has been developed. The electrode is based on classical amperometric detection of hydrogen peroxide produced by the enzyme lactate oxidase, immobilised in a glutaraldehyde matrix. The sensor system comprises an outer poly(vinyl chloride), PVC, membrane with...
Article
Poly(vinyl chloride) (PVC) membranes modified with the surfactants Tween 80, Triton X-100 and bis(2-ethylhexyl) hydrogenphosphate (BEP) have been developed which mimic the high permeability and selectivity properties of conventional dialysis membranes to a range of low molecular weight solutes. Surfactant loss from the membrane matrix (through phys...
Article
Membranes constituted from polymers of differing intrinsic chemical composition as well as poly(vinyl chloride) (PVC) membranes variously modified with plasticising agents were assessed as potential blood contacting interfaces for enzyme electrode use. PVC membranes modified with the nonionic surfactants Tween 80 or Triton X-100 and anionic bis(2-e...
Article
An enzyme electrode has been developed for the simplified determination of oxalate in human urine. Oxalate oxidase has been co-immobilised with bovine serum albumin (BSA) using glutaraldehyde between polycarbonate or haemodialysis external membranes and an internal cellulose acetate membrane to form a classical oxidase enzyme laminate construction....
Article
Networks of workstations have become increasingly popular for high performance computing. However, in order to become a real alternative for Massively Parallel Processors (MPPs), reliability and efficiency issues must be tackled. In this paper, we identify the key challenges for very large workstation networks, and describe implementation technique...
Article
We report on a novel method of oxidase enzyme electrode response amplification, using unplasticized PVC and plasticized PVC, respectively. The anion exchanger tricaprylylmethylammonium chloride (Aliquat 336s) and hydrophobic isopropylmyristate (IPM) plasticizer have been used together to modify PVC. Resulting structures are anionic substrate select...
Article
AT-cut quartz crystals operating in the thickness-shear mode at 10 MHz have been used to study the viscoelastic changes occurring during the poly- merization and gelling of acrylamide solutions. The gelling process is described in terms of the storage and loss moduli, G@ and GA, or in terms of the shear wave velocity and the attenuation coefficient...
Article
Oxalate oxidase has been immobilized within a membrane laminate. Integration of the laminate within an amperometric electrode afforded a sensor for determining oxalate via electrochemical oxidation of H2O2 and subsequent current generation. A study of novel poly(vinyl chloride) (PVC) and cellulose acetate (CA) membranes with various outer/inner mem...
Article
Since 1962, when the first enzyme electrode was reported, biosensors have been the focus of intensive research and have captured the interest and imagination of both the wider scientific and lay communities. They have a wide potential applicability encompassing both biomedical and industrial areas and offer a unique route to simplified, reagentless...
Chapter
Various solids, solid/liquid composites and quasi-liquid membranes have been developed to protect the enzyme layer and working electrode of enzyme electrodes. These include isopropyl myristate-containing porous membranes, liposomes and PVC with a high plasticiser content. The additional value of such membranes beyond their surface ‘biocompatibility...

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Project (1)
Project
Protein Crystallization via Smart material MIPs