Search

The present research demonstrates the design and development of a dual-compartment water purification proto-plant for microbial degradation of organic waste using microbial fuel cell technology and adsorptive removal of inorganic pollutants present in sewage water using highly crystalline chitosan grafted polyaniline (CHIT-g-PANI) and rice husk derived adsorbent. The materials were characterized by UV–Vis, infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and relevant standard methods. The observed results revealed the highly crystalline, biocompatible, porous nature of CHIT-g-PANI as electrode materials for effective microbial degradation of organic wastes of sewage water for generating electricity and water purification. Thus, observed parameters were power density of 6.496 w/m2, sustainable usability for 20 days, and removal of organic waste by 97% from sewage water. Furthermore, the above partially treated water was passed through an adsorption chamber filled with rice husk-derived adsorbents, which removes the 84.5% inorganic impurities of its original concentrations.

An efficient potential triggering process has been established over chemically functionalized sodium alginate grafted polyaniline (SA-g-PANI) under optimum conditions to enable the sensing and extraction of residual mercury ions present in wastewater and soil samples. The observed sensing and extraction parameters were a sensing range of 1.0 nM to 1000 μM, sensitivity of 0.25 mV μM−1 cm−2, response time of 55 s, recovery time of 15 s, limit of detection of 0.33 nM, and a stability of 60 d, along with 78% extraction after the application of an optimized external potential on the sensing electrode. Furthermore, the sensing and extraction mechanism is explained on the basis of the developed induced potential that occurs after the electrochemical surface interaction between Hg2+ and the SA-g-PANI based electrode, along with the repeatability and scale-up possibilities.

Materials having size between 1 and 100 nm, at least in one dimension, are known as nanomaterials. Two-dimensional (2D) materials are a special class of nanomaterials that are ultrathin, having only a single layer of atoms. Because of their large surface area, 2D layered nanomaterials exhibit special properties. The peculiar electronic properties of graphene drew a lot of attention toward the 2D structures. Other than graphene, 2D materials are hexagonal boron nitride (hBN), different transition metal chalcogenides, germanane, silicene, and phosphorene. The layered structures of 2D materials have properties to act as lubricants. These materials show a range of electronic properties and may be used in nanoelectronics, optoelectronics, catalysis, sensors, energy storage, and flexible devices in the future. In this chapter, some of the attributes, such as electronic, optoelectric, optical, electric, thermal, magnetic, and mechanical properties, have been discussed.

The present paper reports the synthesis of α-Fe2O3 by nitrate eutectic melt method and PANI/α-Fe2O3 composite by in-situ polymerization and composite formation (I.P.C.F.) technique at ambient condition. The prepared samples were characterized using infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscope (SEM), and UV–VIS spectroscopy (UV–VIS). The result reveals that prepared composite is crystalline in nature along with improved stability. Further, electrical properties reveals the formation of PANI/α-Fe2O3 composite with improved electrical conductivity than α-Fe2O3 and polyaniline. The electrical resistance of a PANI/α-Fe2O3 film casted on a glass substrate was measured as function of relative humidity in the range of 10–95% maintained by salt solution method to explore its use for humidity monitoring purposes. Finally, PANI/α-Fe2O3 promises a perspective materials for humidity sensing applications.

The present research manuscript demonstrates the chemiresistive sensing of volatile ammonia from the soil over zinc oxide encapsulated polypyrrole (ZnO-en-PPy) composite prepared by in-situ chemical polymerization technique using ferric chloride as a polymerizing agent. The observed analytical result revealed the formation of nanocomposite with optimized crystallinity, improved thermal stability, and responsive electrical conductivity against ammonia concentration. Further, a thin film of the composite was casted on a glass rod to prepare a portable resistive type ammonia sensor for atmospheric and volatile ammonia from the soil with observed sensing parameters i.e. sensitivity range of 1 ppm–100 ppm, sensitivity 0.4947 kΩ-ppm−1, response time 45 s, recovery time 55 s, and stability for 90 days.

The opto-chemical glucose sensing over cupric ion doped polyaniline (Cu+2/PANI) hybrid polymer matrix coated glass rod based optode has been demonstrated.Cu+2/PANI hybrid matrix was synthesized by in situ chemical polymerization of intrinsically functionalized aniline. Furthermore, developed optode has been explored for direct oxidisation of glucose on Cu+2/PANI hybrid matrix for non-enzymatic glucose sensing employing O-dianisidine indicator system. The proposed glucose sensor works well in range of 50 mg/dL–200 mg/dL with response time of 15 s in artificial as well as in biological samples along with 40 days of lifespan. © 2016 Elsevier B.V.

Nanoscandate cathode (NSC) has several advantages over a conventional scandate cathode in terms of emission uniformity, resistance to ion bombardment, and long life. In the present technology of “Yttrium-doped NSC,” yttrium oxide (Y2O3) is codoped with tungsten powder, scandium oxide, and other impregnant materials to make nanopowder using the solgel technique. The pellets, made out of powder, were integrated with potted heaters. The cathodes were analyzed in an analytical chamber containing: 1) Auger electron spectroscopy for surface analysis; 2) anode for emission measurements; and 3) thermionic emission microscope (THEM) for studying emission uniformity. It was found that by adding a small amount of yttrium oxide of 3%–5% by weight increases the emission uniformity of cathode significantly as observed through THEM. Emission current density of more than 80 A/cm2 was drawn from these cathodes under deep space charge conditions.

An experiment was conducted on 20 year old trees of Mallika mango to assess the yield, nutrient contentsand enzymatic and protein activities as influenced by different boron treatments. Results indicated that thelower foliar B content (15.3 to 24.1 mg kg−1) and yield were significantly correlated. Highestpulp B content wasobserved in metalosate treated (T-9) fruits (4.30 mg kg−1) as compared to control (2.63 mg kg−1), boric acid spray (3.17 to 3.47 mg kg−1) and soil application of borax (3.33 mg kg−1). Boron spray improved thefruit yield which, inturn showed positive and significant correlation with pulp B content (r = 0.727*). Enzymatic activities like thatof invertase increased inmetalosate treated fruits as compared to control. A range of 0.002 to 0.028 and 0.013to 0.0145 ΔOD/ 100 mg fresh weight polyphenol oxidase (PPO) was recordedamong the treatments. The proteincontent increased significantly in the B treated plots (T-9 and T-10) as compared to its non-application withthe highest being 0.854 and 0.974 mg per 100 mg tissue protein in the respective years. The study concludedthat foliar or soil application of B proved effectivein the improvement of quality in respect of pulp nutrientsand protein content of mango cv. Mallika.

The present study aimed at in assessing the efficacy of boron supplements (foliar application of B metalosate, boric acid and soil application of borax) on 20 yr old tress of mango cv. Mallika. Changes in foliar boron status indicated that both after the first and second spray, leaf B content was higher in B metalosate treated mango trees as compared to control and soil application of borax + NPK. After first spray, boron status in leaves was found enhanced from 19.6 to 38.3 while from 22 to 32.6 ppm after second spray during 2015-16 fruiting season. Similarly, after first spray boron status in leaves was found enhanced to 21.2 to 36.1 while it was from 19.5 to 39.3 ppm after second spray. Improvement in fruit weight and productivity was recorded in boric acid and B metalosate treated plots as compared to control (NPK) and soil application of B coupled with NPK. A range of 31.46 to 44.77 and 39.42 to 53.57 kg per tree of Mallika fruit yield was recorded in control and different B supplements treated plots during 2015-16 and 2016-17 fruiting seasons, respectively. Quality parameters of mango cv. Mallika were also influenced significantly in response to application of various boron treatments. Thus, the results concluded that B nutrition should be adopted as a practice for improving the productivity and quality in mango Mallika.

We have synthesized a nanocomposite consisting of crystalline tin oxide (SnO2) nanoparticles and polyaniline (PANI) by in-situ polymerization and composite formation (IPCF). The structure and morphology was characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). The nanocomposite is shown to represent a viable material for electrical resistivity based sensing of humidity in the 5 to 90 % relative humidity (RH) range. The electrical resistance of the composite linearly decreases from 127.5 to 11.5 kΩ with humidity from 5 to 95 %. The sensitivity is 0.22 % RH‾1, the response time is 26 s, and the recovery time is 30 s. The fabrication of SnO2/PANI composite combines the high sensitivity of SnO2 towards moisture with good electrical conductivity of PANI, which influences the electronic properties of the material and enables the design of more efficient humidity sensors. The water vapor layering growth kinetics on the composite was investigated by isothermal thermogravimetric analysis and an interaction with limited diffusion aggregate type kinetics has been proposed.

Clonazepam, (5-(2-Chlorophenyl)-7-nitro-1,3-dihydro-1,4-benzodiazepin-2-one), a nitrobenzodiazepine and a scheduled drug, is one of the most highly abused drugs in recent times. A sensitive analytical methodology using Liquid Chromatography tandem Mass Spectrometry (LC-MS/MS) was developed for the determination of clonazepam in human hair and nail samples. The method involves the decontamination of hair and nail using 2 mL each of 0.1% SDS (sodium dodecyl sulfate), water, and methanol, dried followed by incubation in phosphate buffer (pH = 8), extraction with diethyl ether:chloroform (70:30, v/v), separation, and detection using liquid chromatography–tandem mass spectrometry. The method was totally validated with the limit of detection (LOD) of clonazepam estimated as 0.50pg/mg and the limit of quantification (LOQ), 2.0pg/mg of hair and nail. Linearity was observed in the range 2.0 pg/mg to 5000 pg/mg with r2 > 0.9980. The extraction recoveries, intra-day and inter-day precisions, accuracy, and matrix eff...

Novel acid catalysts for alkane isomerization were synthesized with silica alumina supported heteropolyoxometallets by wet incipient method. Two series of catalysts were prepared by dispersing TPA or MPA. Characterization of catalysts was done by BET and TPD methods. Objective was to find high surface and acidity catalysts and to see the effect of synthesis parameter as loading or impregnation time on catalyst physicochemical properties as surface area, pore size, pore volume and acidity of HPA based oxide Seralox-5. TPA or MPA loading affected acidity and pore volume of catalysts, however no effect of impregnation time has been revealed. Surface area of catalysts was found in the range of 154–198 m2/g and acidity 10.1–17.7 ml/g of NH3 at STP. Among all the catalysts optimum characteristic catalysts were found from both the series, selecting one from each. These two catalysts exhibit high surface area, mesopore structure and high acidity.

A simple and time-efficient UV spectrophotometric method was developed for the determination of sucralose in artificial sweeteners. The procedure is based on the UV spectrophotometric determination of the photodegraded product at 270 nm in alkaline medium (pH 12). LOD for this method was 0.02 g/L, and the calibration curve was found to obey Beer's law in the concentration range of 0.1 to 1.2 g/L, with a correlation coefficient (R2) value of 0.9977. The proposed method was studied for accuracy and precision.

Aim: It is important in toxicological/drug screening work to rule out the possible interfering analytes, to eliminate the false positive or negative results. In this paper, we describe a simple, selective, and sensitive derivatized GC-MS method for the determination of cyclohexylsulfamic acid (cyclamate) in urine. Materials and Methods: Elite- 5MS capillary column was used for the separation of analytes and detection using GC-MS. The analysis was carried out in selected ion monitoring mode (SIM) in the range of 26 to 200 using m/z values of 57, 30, 55, 41, 44, 67, 82, 98, and 39. Results and Discussion: The method is based on the conversion of cyclamate into nitroso derivative of cyclamate followed by its gas chromatography-mass spectrometry determination. The limit of detection, limit of quantitation, and linearity range of the proposed method were found to be 0.2 μg/ ml, 0.7 μg/ml, and 1-15 μg/ml, respectively. The recovery of the present method is in the range of 88-94%. Conclusion: The proposed method can be applied for detection and quantification of cyclamate in urine.

Manufacturing and marketing of the spurious health drink by either imitating or copying the original Glucon D, Glucose D and Glucon C (dextrose monohydrate) are commonly encountered in the Indian drug market. Such cases are registered under Section 420 IPC (Indian Penal Code) r/w 63 copyright act. Authors have successfully carried out the identification and quantitation of the contents of spurious health drinks in actual cases received in the laboratory. The questioned samples were thoroughly analysed by chemical and instrumental methods 1 , 2 such as solubility, pH, presumptive colour tests, and identification of dextrose monohydrate, citric acid, cations and anions (calcium, chloride, phosphate and sulphate), and percentage purity 1 of dextrose monohydrate by digital polarimeter. The results were compared with the results obtained with standard reference materials (SRMs) and pure dextrose standard EXCELAR grade as well as genuine samples. The study of the extraneous materials present in these samples was done by further chemical and instrumental analyses by which it was revealed that saccharin and starch were used for manufacturing these spurious products.

A thin-layer chromatographic (TLC) method is developed for the analysis of cefixime using precoated silica gel 60F254 TLC aluminum sheets as stationary phase. The mobile phase was optimized to ensure that no other drug from cephalosporin class and degradation products (formed under stress condition) of the drug interfered with the estimation. By using toluene-ethyl acetate-formic acid-water (10:58:22:10, ν/ν) as mobile phase, a sharp, well-defined, and symmetrical peak was obtained in the chromatogram with an RF value 0.54 ± 0.02. Densitometric measurement was made in the reflectance/absorbance mode at 293 nm. The calibration curve was established as dependence of peak area on amount 500–1500 ng. The second-order polynomial fit was deduced to be suitable for the quantitative analysis. The method was validated as per International Conference on Harmonization guidelines. The method is simple, sensitive, selective, and precise. It can be applied for the quantitative analysis of cefixime in raw materials, mar...

A simple, accurate, and inexpensive high-performance thin-layer chromatography (HPTLC) method has been established for analysis of saccharin in foodstuffs, for example cola drinks, lemon juices, betel nut powder, mouth fresheners, ice candy, and tabletop sweeteners. Chromatography was performed on silica-gel 60 F254 plates with chloroform-methanol-acetic acid 64:35:1 or acetone-isopropanol-acetic acid 60:39:1 as mobile phases. The bands corresponding to the saccharin were scanned in absorbance mode at 230 nm. The calibration plot showed peak area was a linear function of concentration over the range 250–1250 ng μL−1. The relationship between peak area and the amount of saccharin was evaluated by linear regression analysis. The limits of detection and quantification of saccharin were 40 and 130 ng, respectively. Mean recovery from spiked samples was 102.3% for cola drinks and 98.8% for lemon juices. Relative standard deviation (RSD) for cola drinks, lemon juices, ice candy, mouth freshener, betel nut powde...

A comparative study on antioxidative effects of vitamin E, amla-electrolyte (Electrolyte mix of Emblica officinalis) and mint (Mentha longifolia) supplementation in broilers was conducted during the summer months of May-July with temperature-humidity index ranging from 73 to 80. Day old broiler chicks (n=75) were randomly divided into five groups. Control group was given basal diet and treatment groups were supplemented with either Vitamin E (200mg/kg feed), dried mint leaves (10g/kg and 30g/kg feed) or amla-electrolyte mix (1g/kg feed) from day 1 to seven weeks of age. Control group at 3rd and 5th week showed high concentration of lipid peroxidation and low activity of glutathione (GSH) and superoxide dismutase (SOD) in erythrocytes, heart, liver and brain cortex. Antioxidants supplemented groups showed significantly reduced level of lipid peroxidation in erythrocytes both at 3rd and 5th week and in tissues. The GSH, catalase, SOD and glutathione reductase activities were elevated in erythrocytes whereas GSH and SOD activities were depressed in treated birds. It can be concluded from the results that oxidative stress in broilers during summer could be ameliorated using herbal antioxidants.

Functional carbon nanotubes (CNT) have attracted much attention for analytical and biomedical applications. This paper describes the fabrication of a cholesterol oxidase (ChOx) immobilised polyaniline (PANI)/CNT composite electrode for the amperometric detection of cholesterol. The prepared ChOx/PANI/CNT/Au bioelectrode bound ChOx via the available functionalties of PANI (-NH2) and CNT (-COOH). Moreover, the CNT creates a network inside the matrix that strengthens the mechanical property of the bioelectrode. The multifunctional matrix is presumed to provide a 3D-mesoporous surface, which substantially enhances enzyme activity. The linear range of the biosensor for cholesterol oleate was 30-280 μM with a response time of 10 sec.

A detailed metallurgical investigation was undertaken to ascertain the cause of the premature cracking of inner covers used in the batch annealing furnaces of Bokaro Steel Plant of the Steel Authority of India Limited (SAIL). It was found that the cracking was a result of the profuse precipitation of chromium carbide. Precipitation of chromium carbide sensitizes the steel to corrosion attack because of denudation of chromium from the matrix. Use of a properly stabilized austenitic stainless steel was recommended for prolonged life of the inner covers.

We report the facile fabrication of a self-reporting, highly sensitive and selective optical urea nanobiosensor using chitosan-g-polypyrrole (CHIT-g-PPy) nanomicelles as a sensing platform. Urease was immobilized on the spherical micellar surface to create an ultrasensitive self-reporting nanobiosystem for urea. The resulting nanostructures show monodisperse size distributions before and after enzyme loading. The critical micelle concentration of the enzyme-immobilized polymer nanostructure was measured to be 0.49 mg/L in phosphate buffer at pH 7.4. The nanobiosensor had a linear optical response to urea concentrations ranging from 0.01 to 30 mM with a response time of a few seconds. This promising approach provides a novel methodology for self-reporting bioassembly over nanostructure polymer micelles and furnishes the basis for fabrication of sensitive and efficient optical nanobiosensors.

Saccharin, a low calorie artificial sweetener was found as a new diluent / adulterant present along with paracetamol and phenacetin in an illicit methaqualone sample. All these components were simultaneously analyzed by the proposed reverse phase high performance liquid chromatography method using C18 column using acetonitrile: water (90:10 v/v) as mobile phase with a flow rate of 1mL / min. The percentages of saccharin, phenacetin, paracetamol and methaqualone in illicit drug sample were found to be 15.0, 45.6, 25.1 and 12.0 respectively. The method was validated for limit of detection, limit of quantification, linearity, accuracy, precision and reproducibility with the help of the exhibit and simulated samples. The proposed method is simple, accurate and fast. It can be applied to the routine analysis of illicit methaqualone samples as well as for their impurity profiles for tracing the origin.

Nux-vomica is a tropical plant that contains two ergot alkaloids i.e. strychnine and brucine which have pharmaceutical and toxic properties. In some places, for example in India, Nux-vomica is used in ayurvedic preparations in homeopathic medicine. As both compounds are toxic monitoring is required. In this work a method for the chromatographic determination of strychnine and brucine in various herbal/ayurvedic sample preparations, homeopathic medicines, containing Nux-vomica, seeds of Nux-vomica as well as in spiked serum and real urine samples are described. The method involves a direct injection micellar liquid chromatography technique that was optimised under ICH guidelines. Optimum conditions are a mobile phase composed by 0.10 M SDS-pentanol 4% (v/v)-NaH2PO4 buffered at pH 3 with UV detection at 258 nm, flow rate of 1 mL min−1, and temperature 25 °C. Under these conditions strychnine and brucine were analyzed in 15 and 11 min, respectively. Validation studies using ICH guidelines were performed to show that the proposed method was linear (r2 > 0.9997), with LODs (0.18 and 0.09) and LOQs (0.69 and 0.35), for strycnine and brucine, respectively. Repeatability intra- and inter-day was below of 2.50. The developed method can be useful for analyzing strychnine and brucine for quality control and other related forensic and clinical cases.

A potentiometrically tuned-glucose biosensor was fabricated using core-shell nanocomposite based on zinc oxide encapsulated chitosan-graft-poly(vinyl alcohol) (ZnO/CHIT-g-PVAL). In a typical experiment, ZnO/CHIT-g-PVAL core-shell nanocomposite containing 0.04 V/mu M and a response time of three sec. ZnO/CHIT-g-PVAL core-shell nanocomposite could be a promising nanomaterials for a range of enzymic biosensors. European Commission FP7 (PIIF-GA-2009-254955)

ZusammenfassungEs ist bekannt, daß nach Applikation radioaktiver Komplexe für Tumordiagnostik oder -therapie, wie 67Ga-Zitrat oder Radiolanthanid-Komplexe (167Tm- oder 169Yb-Nitrilotriazetat, -Zitrat, -α-Hydroxyisobutyrat, 90Y-Zitrat etc.) die Aktivität nicht nur im Tumor, sondern auch in anderen Organen, vor allem in Leber und Knochen, akkumuliert wird. Dieses Verhalten ist das Haupthindernis für eine medizinische Nutzung. Kürzlich publizierte Ergebnisse gaben Veranlassung, Ethylendiamintetramethylenphosphonat (EDTMP) zur Reduktion der extratumo- ralen Leberaktivität einzusetzen. Die Ergebnisse zeigen, daß schon kleine EDTMP-Mengen (1–2 mg/kg KG) zur Verringerung der Leberaktivität um ca. eine Größenordnung ausreichen. EDTMP verursachte eine verstärkte Radionuklidelimination aus Tumor, Skelett und anderen Geweben, aber in viel geringerem Ausmaß als aus der Leber. Tumor/Leber-Quotienten > 5 sind auf diese Weise erreichbar.

Interaction in the methanol-water system has been studied (i) by the measurement of the mobile phase migration rate in mixed solvents of different composition and (ii) by the changes in chromatographic behaviour of hexacyanoferrate (III) and (II) anions produced by the solvent system. The formation of semi-, mono-, di-, and trihydrates of methanol has been observed. Paper chromatographic separation of hexacyanoferrate (III) and (II) anions has been achieved in the concentration range 85 to 65% (v/v) aqueous methanol, used as a mobile phase.

The aqueous polymerization of methyl methacrylate (MMA) initiated by the potassium bromate-thiomalic acid (TMA) redox system was investigated in the presence of atmospheric oxygen at 35 ± 0.2°C. As the monomer MMA concentration and initiator KBrOs concentration were increased, there was a corresponding increase in both the initial rate and limiting conversion. It was observed that with an increase in activator TMA concentration both the initial rate and the maximum conversion increased up to a certain limit. There was then a fall in initial rate and maximum conversion. The rate of polymerization is given by the relation where x = 1.06 and 0.06 for lower and higher initiator concentrations, respectively. The energy of activation (Ea) was calculated from an Arrhenius plot and found to be 57.98 kJ/mol (13.36 kcal/ mol) under the temperature range investigated (20–45°C).

Benzidine in dilute acetic acid reacts with perbromate ion to give initially a blue colored spot which, on further heating, changes to a dark bluish-grey spot. The latter serves as a sensitive clean test for the detection of perbromate ion on paper and thin-layer chromatograms and electrophoregrams. The reagent can also be used to detect bromate, iodate and periodate ions as well as free halogens.

The graft copolymerization of poly (methyl methacrylate) [PMMA] onto wool initiated by the potassium persulfate-thiomalic acid (TMA) redox couple has been investigated in the presence of atmospheric oxygen. The percentage of grafting efficiency and polymerization as a function of initiator, activator, monomer, temperature, time, and wool was estimated. Evidence of grafting was confirmed by IR spectroscopy. It was observed that the grafting ranged from 25 to 70% depending upon the concentration of the redox system, the time, and the temperature.

The redox system composed of potassium bromate and thiomalic acid was used to initiate the aqueous polymerization of methyl methacrylate under nitrogen atmosphere at 35 ± 0.2°C. The initial rates of polymerization have been found to be approximately proportional to the first power of the initiator concentration in the range of 2.5 to 6.0 ± 10−3 M and to the first power (1.15) of monomer concentration in the range of 3.72 to 11.16 ± 10−2 M The overall rate was independent of activator concentration, approaching a maximum at 10 × 10−3 M. The overall energy of activation was found to be 8.80 kcal/mol. The initial rate and the maximum conversion attained a maximum value at 35°C in the temperature range of 20 to 45°C.

The aqueous polymerization of methyl methacrylate (MMA) initiated by potassium persulfate (I)-thiomalic acid (TMA) redox couple has been studied at 30 ± 0.2°C under nitrogen atmosphere. The rate of polymerization is given by up to 20.0 mmol/L TMA concentration, where x = 0.52 for the I concentration 0.6–10 mmol/L and x = 0.27 for higher I concentrations. The temperature had a marked effect on initial rate and maximum conversion. The overall energy of activation was found to be 11.79 kcal/mol (49.31 kJ/mol). Injection of more initiator (I) at intermediate stages enhanced both the initial rate and maximum conversion. Ag (I) and Fe (III) depressed initial rate as well as maximum conversion, while Cu (II) activated the polymerization. The effect of solvent was also studied.

The potential of dimethyl sulphoxide (DMSO) as a mobile phase for chromatography on ready-for-use, thin-layers of silica gel, cellulose, and alumina has been examined with ferro- and ferricyanide anions, applied alone or as a mixture, as systems to be separated. The most satisfactory results, with very compact spots, are observed with silica gel thin-layers. The behaviour on cellulose layers is similar to that on paper, but the chromatographic spots are more compact in the former case, and therefore the separation there is much cleaner and more rapid. On alumina layers both the anions are highly adsorbed at the point of application, and ferrocyanide is rapidly oxidized to ferricyanide in the presence of DMSO. Alumina layers are therefore unsuitable for chromatography in the present system. The differentiative behaviour of DMSO towards the two closely similar anions is explained by considering the semipolar nature of the S−O bond, the molecular and electronic structure of DMSO, and the difference in ionic volume and ionic charge of the two anions.

The reduction of pertechnetate ion by dilute hydrochloric acid has been shown to be accelerated by the addition of bromide or iodide ions to the reaction mixture. At room temperature, concentrated hydrochloric acid requires an aging of two years to reduce pentavalent technetium, produced in the first stage byan instantaneous reduction of pertechnetate ion, to chromatographically pure technetium (IV). The rate of the reduction of pertechnetate ion by concentrated hydrochloric acid was found to be independent of the concentraton of ammonium pertechnetate in the range of 0.3–8 mg/ml.

The chromatographic behaviour of all alkali metal ions in phenol saturated with 2M hydrochloric acid has been examined by centrifugal and ascending chromatography. Separation with centrifugal development is about one hundred times more rapid than that obtained by the ascending technique. The shortest separation time achieved in these studies, six minutes, shows that centrifugal chromatography promises to be a useful rapid technique for the separation of short-lived fracium isotopes from a mixture of other alkali metals and for the routine analysis of alkali metals. The different degree of solvation of the cations by phenol, depending upon ionic size, is considered to be mainly responsible for the observed selective distribution of the alkali metal ions on the chromatogram.

Complex formation in acetone-water systems has been investigated by studying solvent migration rate and chromatographic behaviour of hexacyanoferrate (II) and (III). The formation of mono-, tetra-, and decahydrates of acetone has been observed, of which the tetrahydrate, also observable by other physical properties of the solvent mixture, is the most stable.

The thyroid gland is one of the organs frequently imaged in nuclear medicine laboratories (1). The most commonly used radiopharmaceutical for its visualization is the pertechnetate-99m ion. During our studies over several years using the generator-produced pertechnetate-99m ion, we sometimes observed a more or less diffused concentration of Tc99m in the neck of the patient with no image of the thyroid gland. Chromatographic and electrophoretic examination of this pertechnetatc-99m eluate showed the anion to be transformed into other Tc99m species with chromatographic and electrophoretic behaviour quite different from that of the pure pertechnetate-99m ion. The quality of the thyroid scintigram depended on the amount of the free pertechnetate-99m present in the eluate.

In the preface to the book “Therapeutic Use of Artificial Radioisotopes”, P.F. Hahn wrote (1) in 1956: “Ideally, one looks for an agent that will seek out and destroy cancer”. 13 Years later in 1969, Edwards and Hayes (2) reported “Tumour scanning with 67Ga citrate”. In 1971 Hart and co-workers observed antitumour activity of gallium nitrate in rodents and suggested the potential usefulness of gallium for treatment of various solid tumours in man (3,4). During the last 15 years since the report of Edwards and Hayes (2), much effort has been devoted to improve the tumour imaging results with 67Ga and also to get satisfactory treatment of various tumours in rodents with gold gallium (5). Although 67Ga citrate is widely used for tumour (6) and abscess detection (7), a positive finding is often doubtful due to following difficulties still encountered during radionuclidic examinations with this radiopharmaceutical (8,9).