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Molecularly imprinted polymers (MIPs) for 17β-estradiol were prepared following a multistep procedure including swelling and polymerization using polystyrene seeds, 4-vinylpyridine as the functional monomer and ethylene glycol dimethacrylate (EDMA) as crosslinker. Dibutylphthalate (DBF) and toluene were employed as swelling and porogenic compounds. All the samples showed a mono- modal and very narrow diameter distribution with mean diameter values in the 2.0-4.7 μm range. The microspheres prepared in the presence of the template molecule present surface available vinyl pyridine unit content higher than those prepared without the template. The amphiphilic nature of the pre-polymerization complex between vinyl pyridine and 17β-estradiol can be claimed to be responsible for a preferential location of the vinyl pyridine units at the microsphere surface. The ability of molecular recognition depends on the accessibility of interaction sites located on surface of polymeric particles that increases when the ratios EDMA/polystyrene seed and DBF/polystyrene seed increase.

A solubility and thermoanalytical study of alkali and alkaline earth solid complexes of pyromellitic acid (1,2,4,5-benzenetetracarboxylic acid, H 4 L) is reported. The insoluble Na + species is Na 2 LH 2 . K + , Rb + and Cs + form MLH 3 . The stoichiometry of precipitation of H 4 L with Ca 2+ , Ba 2+ and Sr 2+ depends on pH: at pH 2 is formed; in the range 4 2 and M 2 L; and at pH > 4.5, only M 2 L is formed. The p K s0 of all the species were determined. The insoluble compounds were also characterized by thermogravimetric analysis.

Thermogravimetric and differential scanning calorimetric methods by stereoscopic and polarising microscopy to identify the nucleus, and IR spectroscopy and X-ray analysis as ancillary analytical tools are applied to the analysis of prostatic calculi.

The thermal properties of some complexes of the Ni(II) with the pyridine-2-aldoxyme (PaOH), where the ligand appears either as ion (PaO − ) or as a neutral molecule, were determined using TG, DTA, HTRS and DRS techniques. The thermal stability, as determined by procedural decomposition temperatures, was The thermal stability is discussed in terms of the intermolecular bonds of the solid lattice and of the electronegativity of the ligands. The thermal decomposition mechanism of the [Ni(PaOH) 2 Cl 2 ] is also examined.

The thermal properties of nickel(II) and zinc(II) complexes of saccharin (sacc) (o-benzoic sulphimide) have been studied and compared both with those of cobalt(II) and copper(II) previously studied and with those of ternary complexes of nickel(II) and zinc(II) having both saccharin and pyridine as ligands. The thermal behaviour is discussed in terms of the interaction between metal and ligands, interaction studied by IR spectroscopy, and by reflectance spectroscopy. The classical thermal stability scale Co(II) > Ni(II) > Cu(II) > Zn(II) is always obtained.

The imidazole ring appears in a number of biological ligands and many different parameters, such as basicity of the ligands, π-electron acceptor ability, steric factors, hydrogen bonding, etc., play an essential role either on the structural types of coordination or on the thermal characteristics of the coordination compounds obtained by reaction of imidazole and its derivatives with transition metal ions. The influence of some of these parameters on the thermal properties of coordination compounds obtained by reaction of imidazole (Im) and N-methyl imidazole (NmIm) with Co(NO3)2, NO(NO3)2 and Cu(NO3)2 is studied here by means of thermogravimetric and differential scanning calorimetric methods supported by infrared spectroscopy. The compounds obtained were Me(L)n(NO3)2 (Me=Co(II), Ni(II), Cu(II); n = 4, 6). The imidazole complexes are always more stable than the corresponding N-methyl imidazole complexes and the ΔH value corresponding to metal-ligand bond breaking is higher for the imidazole compounds. The decomposition mechanisms are also discussed.

The potassium and sodium salts of some penicillins and cephalosporins were analyzed by thermoanalytical techniques (TG, DTG and DSC); in particular, those antibiotics whose thermal decomposition in oxygen occurs too quickly. The analyses were carried out in atmospheres of static air and oxygen, with and without the addition of ammonium sulphate or ammonium persulphate. It is possible to evaluate the purity of these antibiotics from the resultant sodium or potassium sulphate residue. Better results in terms of accuracy and precision were obtained by the addition of ammonium sulphate or persulphate to the analyzed compounds.

Quality control carried out in England has shown the very low reliability of the analysis of renal calculi. Many different analytical techniques have been proposed to solve this problem, and are briefly and critically reviewed in this paper. A method based on thermoanalytical techniques is proposed for obtaining reliable results. The pure substances commonly present in the calculi were first characterised by thermal analysis, derivative thermal analysis, and differential thermal analysis. Synthetic mixtures were then analysed as pellets, simulating the composition of the calculi, and finally, natural renal calculi were studied. The calculi were analysed after dissection, examination by stereoscopic microscopy and polarised light being used to identify a possible nucleus which, when present, was isolated and analysed separately. More than 1000 calculi derived from surgery or from spontaneous emission were analysed. No pretreatment of the calculi is required. The accuracy of the results is about 1.5% and the time required for analysis is about 20 min.

An analytical method for the quantitative determination of some aminoacids is proposed. The analysis is carried out in two steps. The first is based on a thin layer chromatographic separation (TLC) which is realized on alumina and allows the aminoacids to be separated. The second is based on an application of differential scanning calorimetry (DSC), by which it is possible to characterize and determine the amount of the compound contained in each spot, after having removed from the plate the layer corresponding to the spot. This is put in the sample capsule of the differential scanning calorimeter, while the reference capsule is filled with an identical weight of the sample-free aluminium oxide from the same TLC plate. The DSC signal is proportional to the quantity of the sample present in the spot.

The problem of water content modification in tissues, induced by Dupuytren's disease, is treated by differential scanning calorimetry (DSC) and thermal analysis. Two different types of water are found in the pathological tissue instead of the only one found in healthy tissue. At the same time quantitative analysis shows an increase in the total water in the pathological tissue. Finally, the ratio of the heights of the two maxima found in the pathological tissue is proposed as a diagnostic parameter for the evaluation of the development of the pathology.

Complexes of general formula M[H 2 B(Me 2 pz) 2 ] 2 , [where M = Co(II), Ni(II), Cu(II), and Zn(II)] are characterized by thermal analysis and complementary techniques. Mixtures of boron and metal oxides are found as final residues. Relative thermal stability (Ni > Cu > Co = Zn) and thermal behaviour are discussed. Melting and sublimation data are compared with those referred to in the literature.

A series of conjugated and unconjugated cholate sodium salts was analyzed by thermogravimetric (TG and DTG) techniques. The analyses were carried out in static air and oxygen atmosphere. The final residue of the thermal decomposition is sodium carbonate for the glycoconjugates and unconjugated cholates, and sodium sulphate for the tauroconjugates. The possibility of determining the purity of the cholate sodium salts examined, by analysis of the percentage of sodium present in the compounds, was evaluated. Results concerning accuracy and precision for the examined compounds are reported.