Glutamic acid containing supermacroporous poly(hydroxyethyl methacrylate) cryogel disks for UO22+ removal

Supermacroporous cryogel with an average pore size of 10–200 μm in diameter was prepared by cryopolymerization of N-methacryloyl-(l)-glutamic acid (MAGA) and 2-hydroxyethyl methacrylate (HEMA). The poly(HEMA–MAGA) cryogel was characterized by surface area measurements, FTIR, swelling studies, elemental analysis and SEM. The poly(HEMA–MAGA) cryogel had a specific surface area of 23.2 m²/g. The equilibrium swelling ratio of the cryogel is 9.68 g H₂O/g for poly(HEMA–MAGA) and 8.56 g H₂O/g cryogel for PHEMA. The poly(HEMA–MAGA) cryogel disks with a pore volume of 71.6% containing 878 μmol MAGA/g were used in the removal of UO₂²⁺ from aqueous solutions. Adsorption equilibrium of UO₂²⁺ was obtained in about 30 min. The adsorption of UO₂²⁺ ions onto the PHEMA cryogel disks was negligible (0.78 mg/g). The MAGA incorporation significantly increased the UO₂²⁺ adsorption capacity (92.5 mg/g). The adsorption process is found to be a function of pH of the UO₂²⁺ solution, with the optimum value being pH 6.0. Adsorption capacity of MAGA contained PHEMA based cryogel disks increased significantly with pH and then reached the maximum at pH 6.0. Consecutive adsorption and elution cycles showed the feasibility of repeated use for poly(HEMA–MAGA) cryogel disks.     

Poly (hydroxyethyl methacrylate-glycidyl methacrylate) films modified with different functional groups: In vitro interactions with platelets and rat stem cells

Copolymerization of 2-hydroxyethylmethacrylate (HEMA) with glycidylmethacrylate (GMA) in the presence of α-α′-azoisobisbutyronitrile (AIBN) resulted in the formation of hydrogel films carrying reactive epoxy groups. Thirteen kinds of different molecules with pendant NH₂ group were used for modifications of the p(HEMA-GMA) films. The NH₂ group served as anchor binding site for immobilization of functional groups on the hydrogel film via direct epoxy ring opening reaction. The modified hydrogel films were characterized by FTIR, and contact angle studies. In addition, mechanical properties of the hydrogel films were studied, and modified hydrogel films showed improved mechanical properties compared with the non-modified film, but they are less elastic than the non-modified film. The biological activities of these films such as platelet adhesion, red blood cells hemolysis, and swelling behavior were studied. The effect of modified hydrogel films, including NH₂, (using different aliphatic CH₂ chain lengths) CH₃, SO₃H, aromatic groups with substituted OH and COOH groups, and amino acids were also investigated on the adhesion, morphology and survival of rat mesenchymal stem cells (MSCs). The MTT colorimetric assay reveals that the p(HEMA-GMA)-GA-AB, p(HEMA-GMA)-GA-Phe, p(HEMA-GMA)-GA-Trp, p(HEMA-GMA)-GA-Glu formulations have an excellent biocompatibility to promote the cell adhesion and growth. We anticipate that the fabricated p(HEMA-GMA) based hydrogel films with controllable surface chemistry and good stable swelling ratio may find extensive applications in future development of tissue engineering scaffold materials, and in various biotechnological areas.     

Poly(hydroxyethyl methacrylate-co-methacryloylamidotryptophane) nanospheres and their utilization as affinity adsorbents for porcine pancreas lipase adsorption

Novel nanospheres with an average size of 350 nm utilizing N-methacryloyl-(l)-tryptophane methyl ester (MATrp) as a hydrophobic monomer were prepared by surfactant free emulsion polymerization of 2-hydroxyethyl methacrylate (HEMA), (MATrp) conducted in an aqueous dispersion medium. MATrp was synthesized using methacryloyl chloride and (l)-tryptophane methyl ester. Specific surface area of the non-porous nanospheres was found to be 1902.3 m²/g. poly(HEMA–MATrp) nanospheres were characterized by Fourier Transform Infrared Spectroscopy (FTIR) and scanning electron microscopy (SEM). Average particle size and size distribution measurements were also performed. Elemental analysis of MATrp for nitrogen was estimated at 1.36 mmol/g nanospheres. Then, poly(HEMA–MATrp) nanospheres were used in the adsorption of porcine pancreas lipase in a batch system. Using an optimized adsorption protocol, a very high loading of 558 mg enzyme/g nanospheres was obtained. The adsorption phenomena appeared to follow a typical Langmuir isotherm. The K_m value for immobilized lipase (16.26 mM) was higher than that of free enzyme (10.34 mM). It was observed that enzyme could be repeatedly adsorbed and desorbed without significant loss in adsorption amount or enzyme activity. These findings show considerable promise for this material as an adsorption matrix in industrial processes.     

Structural and magnetodielectric properties of poly(vinylidene-fluoride)-[0.8(Bi0.5Na0.5)TiO3-0.2CoFe2O4] polymer composite films

Composite thick films of xPoly(vinylidene-fluoride)-(1−x)[0.8(Bi_0.5Na_0.5)TiO₃-0.2CoFe₂O₄] with x = 0.1, 0.2, 0.3 and 0.4 were synthesized by hot press method. X-ray diffraction pattern of the composite films indicate the existence of distinct peaks of poly(vinylidene-fluoride), (Bi_0.5Na_0.5)TiO₃ and CoFe₂O₄ phases. The value of dielectric loss and saturation magnetization of polymer composite films decrease with increase in poly(vinylidene-fluoride) content. The magnetodielectric effect of the polymer composite films was found to improve with increasing poly(vinylidene-fluoride) content. The linear fitting of Δε ∼ γM² gives the value of magnetoelectric interaction coefficient (γ) of polymer composite films.     

Oriented immobilized anti-LDL antibody carrying poly(hydroxyethyl methacrylate) cryogel for cholesterol removal from human plasma

Low density lipoprotein (LDL) cholesterol is a major ingredient of the plaque that collects in the coronary arteries and causes coronary heart diseases. Among the methods used for the extracorporeal elimination of LDL from intravasal volume, immunoaffinity technique using anti-LDL antibody as a ligand offers superior selectivity and specificity. Proper orientation of the immobilized antibody is the main issue in immunoaffinity techniques. In this study, anti-human β-lipoprotein antibody (anti-LDL antibody) molecules were immobilized and oriented through protein A onto poly(2-hydroxyethyl methacrylate) (PHEMA) cryogel in order to remove LDL from hypercholesterolemic human plasma. PHEMA cryogel was prepared by free radical polymerization initiated with N,N,N′,N′-tetramethylene diamine (TEMED). PHEMA cryogel with a swelling degree of 8.89 g H₂O/g and 67% macro-porosity was characterized by swelling studies, scanning electron microscope (SEM) and blood compatibility tests. All the clotting times were increased when compared with control plasma. The maximum immobilized anti-LDL antibody amount was 63.2 mg/g in the case of random antibody immobilization and 19.6 mg/g in the case of oriented antibody immobilization (protein A loading was 57.0 mg/g). Random and oriented anti-LDL antibody immobilized PHEMA cryogels adsorbed 111 and 129 mg LDL/g cryogel from hypercholesterolemic human plasma, respectively. Up to 80% of the adsorbed LDL was desorbed. The adsorption–desorption cycle was repeated 6 times using the same cryogel. There was no significant loss of LDL adsorption capacity.     

Photochemically promoted degradation of poly(ɛ-caprolactone) film

Poly(?-caprolactone) (PCL) films were doped with photoactive 1,2-diphenylethane-1,2-dione (benzil, BZ), and the effect of the photochemical transformation of benzil on the molecular characteristics of the PCL films and the rate of PCL hydrolysis was studied. Both crosslinking and degradation of the PCL film were observed during irradiation of the PCL/BZ films. Irradiation of a PCL/BZ film at λ > 400 nm under an air atmosphere resulted in a decrease of the average molecular weight (M_n) of PCL to approximately one half, while formation of polar groups and an increase in the hydrophilicity of the PCL film were observed. Moreover, a subsequent hydrolytic test showed a significant increase in the hydrolytic degradation rate of the PCL/BZ film in comparison with non-irradiated or irradiated PCL films without doped benzil. Using benzil as a dopant in the PCL matrix can allow adjusting the degradation rate of PCL, what can be very important from both environmental and biomedical perspectives.     

Immobilization of Acidithiobacillus ferrooxidans on sulfonated microporous poly(styrene–divinylbenzene) copolymer with granulated activated carbon and its use in bio-oxidation of ferrous iron

The immobilization efficiencies of Acidithiobacillus ferrooxidans cells on different immobilization matrices were investigated for biooxidation of ferrous iron (Fe^2 +) to ferric iron (Fe^3 +). Six different matrices were used such as the polyurethane foam (PUF), granular activated carbon (GAC), raw poly(styrene–divinylbenzene) copolymer (rawSDVB), raw poly(styrene–divinylbenzene) copolymer with granular activated carbon (rawSDVB-GAC), sulfonated poly(styrene–divinylbenzene) copolymer (sulfSDVB) and sulfonated poly(styrene–divinylbenzene) copolymer with granular activated carbon (sulfSDVB-GAC). The sulfSDVB-GAC polymer showed the best performance for Fe^2 + biooxidation. It was used at packed-bed bioreactor and the kinetic parameters were obtained. The highest Fe^2 + biooxidation rate (R) was found to be 4.02 g/L h at the true dilution rate (D_t) of 2.47 1/h and hydraulic retention time (τ) of 0.4 h. The sulfSDVB-GAC polymer was used for the first time as immobilization material for A. ferrooxidans for Fe^2 + biooxidation.     

Enhanced stability of catalase covalently immobilized on functionalized titania submicrospheres

In this study, a novel approach combing the chelation and covalent binding was explored for facile and efficient enzyme immobilization. The unique capability of titania to chelate with catecholic derivatives at ambient conditions was utilized for titania surface functionalization. The functionalized titania was then used for enzyme immobilization. Titania submicrospheres (500–600 nm) were synthesized by a modified sol–gel method and functionalized with carboxylic acid groups through a facile chelation method by using 3-(3,4-dihydroxyphenyl) propionic acid as the chelating agent. Then, catalase (CAT) was covalently immobilized on these functionalized titania submicrospheres through 1-ethyl-3-[3-dimethylaminopropyl] carbodiimide hydrochloride/N-hydroxysuccinimide (EDC/NHS) coupling reaction. The immobilized CAT retained 65% of its free form activity with a loading capacity of 100–150 mg/g titania. The pH stability, thermostability, recycling stability and storage stability of the immobilized CAT were evaluated. A remarkable enhancement in enzyme stability was achieved. The immobilized CAT retained 90% and 76% of its initial activity after 10 and 16 successive cycles of decomposition of hydrogen peroxide, respectively. Both the K_m and the V_max values of the immobilized CAT (27.4 mM, 13.36 mM/min) were close to those of the free CAT (25.7 mM, 13.46 mM/min).     

Quasi-solid-state dye-sensitized solar cells from hydrophobic poly(hydroxyethyl methacrylate/glycerin)/polyaniline gel electrolyte

Hydrophobic poly(hydroxyethyl methacrylate/glycerin) [poly(HEMA/GR)] gel with a three-dimensional (3D) framework was successfully fabricated and employed to integrate with polyaniline (PANi). The resultant poly(HEMA/GR)/PANi gel electrolyte exhibited interconnective porous structure for holding I⁻/I₃⁻, giving a similar conduction mechanism and ionic conductivity to that of liquid system but a much enhanced retention of I⁻/I₃⁻ redox couple. Fourier transform infrared spectroscopy, X-ray diffraction patterns, cyclic voltammograms as well as electrochemical impedance spectroscopy were employed to evaluate the molecular structure, crystallinity, and the electrochemical behaviors, showing that the combination of PANi with poly(HEMA/GR) caused a lower charge-transfer resistance and higher electrocatalytic activity for the I₃⁻/I⁻ redox reaction in the gel electrolyte. An efficiency of 6.63% was recorded from the quasi-solid-state DSSC assembled with the poly(HEMA/GR)/PANi gel electrolyte at 100 mW cm⁻².     

Melting, crystallization and optical behaviors of poly (ethylene terephthalate)-silica/polystyrene nanocomposite films

Poly (ethylene terephthalate) (PET)-silica (SiO₂)/polystyrene (PS) nanocomposite films were prepared by melting PET with the core-shell SiO₂/PS nanoparticles. Differential scanning calorimetry (DSC) results showed that the crystallization temperature of PET-SiO₂/PS nanocomposite films with 2 wt.% PS-encapsulated SiO₂ nanoparticles reached 205.1 °C, 11.6 °C higher than that of PET. For crystallized PET-SiO₂/PS nanocomposite films, double melting peaks appeared in DSC curves similar to PET. Scanning electron microscopy revealed a netlike fibre morphology for the amorphous PET-SiO₂/PS nanocomposite films with 2 wt.% PS-encapsulated SiO₂ nanoparticles. The light transmittance of these amorphous PET-SiO₂/PS nanocomposite films reached 87.9%, compared to 84.2% for PET. With the increase of annealing temperature from 110 to 150 °C, the transmittance of PET-SiO₂/PS nanocomposite films decreased slowly from 69.9 to 46.9%, while their haziness increased slightly from 45.8 to 48.2%. All these phenomena are suggested to result from the strongly heterogeneous nucleation of PS-encapsulated SiO₂ nanoparticles in PET.     

Purification of yeast alcohol dehydrogenase by using immobilized metal affinity cryogels

In this study, poly(2-hydroxyethyl methacrylate–glycidylmethacrylate) [poly(HEMA–GMA)] cryogels were prepared by radical cryocopolymerization of HEMA with GMA as a functional comonomer and N,N′-methylene-bisacrylamide (MBAAm) as a crosslinker. Iminodiacetic acid (IDA) functional groups were attached via ring opening of the epoxy group on the poly(HEMA–GMA) cryogels and then Zn(II) ions were chelated with these structures. Characterization of cryogels was performed by FTIR, SEM, EDX and swelling studies. These cryogels have interconnected pores of 30–50 μm size. The equilibrium swelling degree of Zn(II) chelated poly(HEMA–GMA)-IDA cryogels was approximately 600%. Zn(II) chelated poly(HEMA–GMA)-IDA cryogels were used in the adsorption of alcohol dehydrogenase from aqueous solutions and adsorption was performed in continuous system. The effects of pH, alcohol dehydrogenase concentration, temperature, and flow rate on adsorption were investigated. The maximum amount of alcohol dehydrogenase adsorption was determined to be 9.94 mg/g cryogel at 1.0 mg/mL alcohol dehydrogenase concentration and in acetate buffer at pH 5.0 with a flow rate of 0.5 mL/min. Desorption of adsorbed alcohol dehydrogenase was carried out by using 1.0 M NaCI at pH 8.0 phosphate buffer and desorption yield was found to be 93.5%. Additionally, these cryogels were used for purification of alcohol dehydrogenase from yeast with a single-step. The purity of desorbed alcohol dehydrogenase was shown by silver-stained SDS–PAGE. This purification process can successfully be used for the purification of alcohol dehydrogenase from unclarified yeast homogenates and this work is the first report about the usage of the cryogels for purification of alcohol dehydrogenase.     

Cu(II) complexes imobilized on functionalized mesoporous silica as catalysts for biomimetic oxidations

Mesoporous HMS silica was synthesized and functionalized with 3-aminopropyl-triethoxysilane (APTES) by a post-synthesis method. HMS and NH₂-HMS supports were used for immobilization of two Cu(II) biomimetic complexes ([Cu(acac)(phen)(H₂O)](ClO₄), [Cu(acac)(Me₂bipy)](ClO₄)) or laccase enzyme. Mesoporous structure of the support; functionalization of silica surface, structure of ligands, and Cu complexes; and their immobilization were evidenced by XRD analysis, N₂ adsorption–desorption, SEM microscopy, TGA-DTA, IR and UV–Vis spectroscopy, and elemental analysis. The results confirm the structural integrity of the mesoporous hosts and successful anchoring of the metal complexes over the supports. For comparison, copper-substituted mesoporous silica (Cu-HMS) by using dodecylamine as structure-directing agent was also synthesized. All the synthesized materials were tested for their catalytic activity on the oxidation of 4-aminoantipyridine, 2,2′-azinobis (3-ethyl-benzothiazoline)-sulfonic acid (ABTS) with air, as well as in liquid phase oxidation of anisole and phenol with hydrogen peroxide. In order to verify the complex biomimetic activity, the Trametes versicolor laccase was immobilized by adsorption in the same supports.     

Development of amperometric laccase biosensor through immobilizing enzyme in copper-containing ordered mesoporous carbon (Cu-OMC)/chitosan matrix

A functionalized copper-containing ordered mesoporous carbon (Cu-OMC) which shows good electrical properties was synthesized by carbonization of sucrose in the presence of cupric acetate inside SBA-15 mesoporous silica template. Based on this, a facilely fabricated amperometric biosensor by entrapping laccase into the Cu-OMC/chitosan (CS) film was developed. Laccase from Trametes versicolor was assembled on a composite film of Cu-OMC/chitosan (CS) modified Au electrode and the electrode was characterized. The optimum experimental conditions of biosensor for the detection of catechol were studied in details. Under the optimal conditions, the detection limit was 0.67 μM and the linear detection range was from 0.67 μM to 15.75 μM for catechol. The apparent Michaelis–Menten (K_M^app) was estimated using the Lineweaver–Burk equation and the K_M^app value was 40.2 μM. This work demonstrated that the Cu-OMC/CS composite provides a suitable support for laccase immobilization and construction of biosensor.     

Controlled hydrothermal synthesis of VO2(B) nanobelts

Large-scale VO₂(B) nanobelts have been synthesized by hydrothermal strategy via one-step method using V₂O₅ as vanadium source and C₆H₅-(CH₂)_n-NH₂ with n = 2 and 4 (2-phenylethylamine and 4-phenylbutylamine) as structure-directing templates. The composition and morphology of the nanobelts were established by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FTIR). The as-obtained VO₂(B) nanobelts have a length of 3-10 μm, a wideness of 100-375 nm and a thickness of 30-66 nm.     

Dependence of Zr content on electrical properties of Bi3.15Nd0.85Ti3-xZrxO12 thin films synthesized by chemical solution deposition (CSD)

The Bi_3.15Nd_0.85Ti_3-xZr_xO₁₂ (BNTZ) thin films with Zr content (x = 0, 0.05, 0. 1, 0.15, and 0.2) were prepared on Pt/Ti/SiO₂/Si (100) substrates by chemical solution deposition (CSD) technique. The crystal structures of BNTZ films were analyzed by X-ray diffraction (XRD). The effects of Zr contents on the ferroelectric, dielectric properties, and leakage current of BNTZ films were thoroughly investigated. The XRD results demonstrated that all the films possessed a single phase bismuth-layered structure and exhibited the highly preferred (117) orientation. Among these films, the film with Zr content x = 0.1 held the maximum remanent polarization (2P_r) of 50.21 μC/cm² and a low coercive field (2E_c) of 210 kV/cm.     

Studies on polymer electrolyte poly(vinyl) pyrrolidone (PVP) complexed with ionic liquid: Effect of complexation on thermal stability,conductivity and relaxation behaviour

Polymer electrolyte films of PVP + x wt% ionic liquid (IL) (1-ethyl-3-methylimidazolium tetrafluoroborate [EMIM][BF₄]) for x = 0, 5, 10, 15, 20, 25 wt% have been prepared using solution cast technique. These films were characterized by TGA, DSC, FT-IR and ac impedance spectroscopy techniques. From XRD studies it is found that the inclusion of IL increases the amorphocity of polymeric membranes. DSC thermograms show that the glass transition (T_g) and melting temperatures (T_m) of PVP shift upon complexation with IL. FT-IR analysis shows the complexation of PVP with IL. Thermogravimetric studies show that PVP decomposes in a single step while PVP/IL membranes exhibit two step decomposition; lower value of decomposition temperature corresponds to the decomposition of PVP/IL complex while the higher decomposition temperature has been attributed to the decomposition of PVP. The decomposition temperature of PVP/IL complex decreases with the increasing amount of IL in the PVP membrane. Temperature dependence of conductivity and dielectric relaxation frequencies have also been studied for PVP and PVP/IL membranes. Both show thermally activated Arrhenius behaviour.     

Deposition of WNxCy thin films for diffusion barrier application using the dimethylhydrazido (2) tungsten complex (CH3CN)Cl4W(NNMe2)

Tungsten nitride carbide (WN_xC_y) thin films were deposited by chemical vapor deposition using the dimethylhydrazido (2⁻) tungsten complex (CH₃CN)Cl₄W(NNMe₂) (1) in benzonitrile with H₂ as a co-reactant in the temperature range 300 to 700 °C. Films were characterized using X-ray diffraction (XRD), Auger electron spectroscopy (AES), X-ray photoelectron spectroscopy and four-point probe to determine film crystallinity, composition, atomic bonding, and electrical resistivity, respectively. The lowest temperature at which growth was observed from 1 was 300 °C. For deposition between 300 and 650 °C, AES measurements indicated the presence of W, C, N, and O in the deposited film. The films deposited below 550 °C were amorphous, while those deposited at and above 550 °C were nano-crystalline (average grain size < 70 Å). The films exhibited their lowest resistivity of 840 µΩ-cm for deposition at 300 °C. WN_xC_y films were tested for diffusion barrier quality by sputter coating the film with Cu, annealing the Cu/WN_xC_y/Si stack in vacuum, and performing AES depth profile and XRD measurement to detect evidence of copper diffusion. Films deposited at 350 and 400 °C (50 and 60 nm thickness, respectively) were able to prevent bulk Cu transport after vacuum annealing at 500 °C for 30 min.     

iCVD growth of poly(N-vinylimidazole) and poly(N-vinylimidazole-co-N-vinylpyrrolidone)

The imidazole group plays an important role in α-chymotrypsin catalysis, metal-ion complexation, counterion or dye binding. Poly(N-vinylimidazole), PVI, is also a good model polymer interacting with neutral salts. The poly(N-vinylimidazole-co-N-vinylpyrrolidone) copolymer P(VI-co-VP), can be used to produce highly functionalized polymers.PVI and P(VI-co-VP) thins films were achieved via initiated chemical vapor deposition (iCVD), a solvent-free process to form films under mild conditions. The polymerization was initiated by hot wire heated tert-butyl peroxide (TBPO). The chemical structure and compositions of the polymers were analyzed using FTIR and XPS. The growth rate of PVI as a function of the pressure inside the iCVD reactor was measured to be 1 nm/h mTorr. The XPS results show that the functional groups were retained in the polymer deposited. For the P(VI-co-VP) deposition, there are more VI groups found in the co-polymer chain even when the reacting monomers were fed in the same ratio.     

Effect of biaxial‐simultaneous stretching conditions on OTR and CO2 permeation of CO2 laser perforated poly(lactic acid) film

The biaxially oriented poly(lactic acid) films prepared using simultaneous biaxial stretching were perforated by CO₂ laser with the power of 60 W. The focal spot diameter was fixed at 103 μm. Pulse durations were varied from 1 to 30 μs, which corresponds to the fluence from 1.4 to 42.6 J/cm². The perforated microhole size increased with increasing laser energy. The shape of microholes was circular for the films of equi‐biaxial stretching, whereas elliptical microholes were formed with its long and short axes corresponding to the directions of higher and lower stretch ratios, respectively. Comparing the laser perforation behavior of the as‐drawn films and annealed films, the opening of a microhole in the annealed films started at higher laser fluence, and at the same fluence the size of microhole was smaller. Gas transmission rates of the biaxially oriented poly(lactic acid) films with different thicknesses were examined. The oxygen transmission rates (OTR) of film improved with increased microhole diameter. The OTR of films containing 1 microhole/103 cm² (hole diameter of ~110 μm) was 184, 150, and 98 cm³/d in comparison with the OTR for the original films without microhole of only 16, 10, and 8 cm³/d, respectively. Packaging films with OTR higher than 100 cm³/d (equivalent to the 9700 cm³/m²/d) are required to create a modified atmosphere inside the package of fresh produce for shelf‐life extension. Measured OTR and CO₂TR values of the 3 different shapes of microhole were compared and discussed.     

Properties of one-step synthesized Pt nanoparticle-doped poly(3,4-ethylenedioxy thiophen):poly(styrenesulfonate) hybrid films

Poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) thin films incorporating Pt nanoparticles were synthesized by a simple method using H₂PtCl₆? xH₂O. The surface morphology, chain structure, bonding states, and electronic structure of the films were investigated. Unusual formation of a PEDOT-rich surface was accompanied with interactions between PEDOT:PSS and Pt nanoparticles due to agglomeration of PEDOT:PSS around Pt nanoparticles and destabilization of chain conformation. High doping of the PEDOT moiety occurred during the reduction of H₂PtCl₆·xH₂O so that an increased work function and a decreased energy gap between the edge of the highest occupied molecular orbital and the Fermi level were observed. Intermediate products including chlorine and [PtCl₆]⁻, and the ionic nature of the Pt nanoparticles were responsible for the resultant properties of Pt-PEDOT:PSS. Products generated during the formation of Pt nanoparticles served as a third anionic dopant like PSS and as an inhibitor of segregation.