Introduction An IMS method for determining trace quantities of Dober’s Chematic ® 91AE detergent (an acidic detergent) has been developed using the IONSCAN-LS. The method is based on the detection of the surfactant LAE (linear alcohol ethoxylate), a material also found in other Dober detergents – such as the basic Chematic 82AE and the neutral Chematic 99AE – and variations of this method can readily be developed to analyze for those detergents.

Introduction An IMS method for determining trace quantities of Dober’s Chematic ® 82AE detergent (a basic detergent) has been developed using the IONSCAN-LS. The method is based on the detection of the surfactant LAE (linear alcohol ethoxylate), a material also found in other Dober detergents – such as the acidic Chematic 91AE and the neutral Chematic 99AE – and variations of this method can readily be developed to analyze for those detergents.

An IMS method for determining trace quantities of Dober’s Chematic ® 99AE detergent (a mildly basic detergent) has been developed using the IONSCAN-LS. The method is based on the detection of the surfactant LAE (linear alcohol ethoxylate), a material also found in other Dober detergents –such as the basic Chematic 82AE and the acidic Chematic 91AE – and variations of this method can readily be developed to analyze for those detergents

Until now FT-IR users have been forced to search unknowns against Transmittance Libraries, due to the fact that large ATR Search Libraries were not available. Although transmission libraries can be useful for identifying materials analyzed by ATR, the most reliable identification is obtained when using ATR libraries.

This work reports on a complementary use of surface plasmon resonance (SPR) and quartz crystal microbalance with dissipation monitoring (QCM-D) technologies to study interactions between a peptide antigen and polyclonal antibodies, in an experimental format suitable for diagnostic assays of autoimmune diseases. In the chosen model, a synthetic peptide from the juxtamembrane region of IA-2 (a type 1 diabetes associated antigen) was immobilized by an optimized chemical protocol applicable to both BIACORE and QCM-D sensors. A thorough study of the peptide immobilization was performed to optimize the signal-to-noise ratio using mixed self-assembled monolayers (SAM) on a gold surface. Introduction of polyethylene glycol (EG6) chains into mixed SAM layers and addition of an anionic surfactant to the human serum reduced non-specific binding without modifying the viscoelasticity properties of the layer. Under our conditions, the antibody SPR detection limit was determined to be 0.2nM in diluted human serum. This value is in agreement with the reported rank distribution of IA-2 antibodies in diabetic patient sera. Label-free and real-time technologies such as SPR and/or QCM-D could be precious tools in future diagnostic assays.

We have studied the adsorption kinetics of a small monomeric protein S6 using the quartz crystal microbalance with dissipation monitoring (QCM-D) technique. Competitive adsorption from various proportions of native (Nat) and denatured (Den) protein in the bulk phase was carried out using a range of chemical denaturant concentrations. The ratio between Nat and Den in bulk has a profound affect on the adsorption behavior, most obvious from a significant (one order of magnitude) increase in the rate of a lag
/ and consolidation
/adsorption phase when Nat is the major species present in bulk, signaling that these adsorption phases originates from the Den fraction of proteins in the bulk. To determine whether the kinetics of protein unfolding in the bulk phase are rate-limiting for adsorption of Nat, the adsorption kinetics of wildtype S6 with the mutant VA85 (whose unfolding kinetics are around 30 times more rapid under conditions of equal thermodynamic stability) were compared. It is concluded that adsorption of Nat is not ratelimited by the rate of unfolding in solution, leading to the speculation that Nat, upon binding on the surface, is trapped as a misfolded state whose structural dynamics do not correlate with those of Nat.

Biological charge transfer processes continue to attract attention from the scientific community due to the central importance of these mechanisms in energy cycles in living organisms (Kaim and Schewederski, 1994). Characterizing these processes should lead to a better understanding of the molecular logic of life, but also to new methods of diagnosis and, eventually, therapeutical applications.

The adsorption kinetics of three model proteins—human serum albumin, fibrinogen and hemoglobin—has been measured and compared using three different experimental techniques: optical waveguide lightmode spectroscopy (OWLS), ellipsometry (ELM) and quartz crystal microbalance (QCM-D). The studies were complemented by also monitoring the corresponding antibody interactions with the pre-adsorbed protein layer. All measurements were performed with identically prepared titanium oxide coated substrates. All three techniques are suitable to follow in-situ kinetics of protein–surface and protein–antibody interactions, and provide quantitative values of the adsorbed adlayer mass. The results have, however, different physical contents. The optical techniques OWLS and ELM provide in most cases consistent and comparable results, which can be straightforwardly converted to adsorbed protein molar (‘dry’) mass. QCM-D, on the other hand, produces measured values that are generally higher in terms of mass. This, in turn, provides valuable, complementary information in two respects: (i) the mass calculated from the resonance frequency shift includes both protein mass and water that binds or hydrodynamically couples to the protein adlayer; and (ii) analysis of the energy dissipation in the adlayer and its magnitude in relation to the frequency shift (c.f. adsorbed mass) provides insight about the mechanical/structural properties such as viscoelasticity. © 2002 Elsevier Science B.V. All rights reserved.

科学界把探针与样品之间的距离小于几十纳米的范围称为近场，而大于这个距离的范围叫做远场。显然，STM、AFM 等利用探针在样品表面的扫描的方法属于近场探测，而对于光学显微镜、电子显微镜等远离样品表面进行观测的方法称为远场方法。 正如电子具有隧道效应一样，光子也具有光子隧道效应。研究发现，物体受光波照射后，离开物体表面的光波分为两种成份：一部分光向远方传播，这是传统光学显微镜能接收的信息；而另一部分光波只能沿物体表面传播，一旦离开表面就很快衰减。这部分在近场传播的光波又叫隐失波。由于隐失波携带有研究样 品表面非常有用的信息，科学家一直设想能对这种近场的光波加以研究利用。STM 新颖的设计思想的出现，为近场光学的研究提供了思路。于是一种新型的科研仪器，近场光学显微镜诞生了。

科学界把探针与样品之间的距离小于几十纳米的范围称为近场，而大于这个距离的范围叫做远场。显然，STM、AFM 等利用探针在样品表面的扫描的方法属于近场探测，而对于光学显微镜、电子显微镜等远离样品表面进行观测的方法称为远场方法。

The first graph shows three samples undergoing phase change. water, saturated salt solution (melting point –21DegC) and Styrene (melting point –30.6 DegC). Note how the temperature difference between the ice and the air bath and the water and the air bath are very different.

近场探测原理，悬臂式光纤探针等．介绍光纤探针的制作方法，科学界把探针与样品之间的距离小于几十纳米的范围称为近场，而大于这个距离的范围叫做远场。显然，STM、AFM 等利用探针在样品表面的扫描的方法属于近场探测，而对于光学显微镜、电子显微镜等远离样品 表面进行观测的方法称为远场方法。

Examples are given of how the Rapid Screening Device (RSD) can give vital information to allow safe processing, safe storage and safe transportation of hazardous and potentially exothermic materials. The RSD is a new technique of relatively low cost but rapidly and safety will give quality temperature and pressure data on any exothermic (and endothermic) reaction – up to 6 samples may be tested simultaneously. The RSD is an ideal first instrument for a company investing in chemical safety measurement. It is easy to use and the data produced is simple to understand. Applications (as given) range from low energy to high energy reactions; eg chemicals, monomers, reactive mixtures, propellants or explosives.

Abstract: Examples are given of how the Rapid Screening Device (RSD) can give vital information to allow safe processing, safe storage and safe transportation of hazardous and potentially exothermic materials. The RSD is a new technique of relatively low cost but rapidly and safety will give quality temperature and pressure data on any exothermic (and endothermic) reaction – up to 6 samples may be tested simultaneously. The RSD is an ideal first instrument for a company investing in chemical safety measurement. It is easy to use and the data produced is simple to understand. Applications (as given) range from low energy to high energy reactions; eg chemicals, monomers, reactive mixtures, propellants or explosives.

In this news letter we will inform about how you can extract that extra information from　your samples by combining Raman, FT-IR, NSOM (NearField Scanning Optical　Microscopy) and AFM (Atomic Force Microscopy). We also have an interesting Raman　application　presented by conservator Cecilia Rönnerstam, National Museum of Fine Arts in　Stockholm.

The spatial resolution of Raman systems employing normal optical microscopes is limited to approximately the wavelength of the light (about 0.5 µm), because both the illuminating laser light and the Raman scattered light are collected in the optical far-field (i.e. many wavelengths of light away from the scattering material).

Hits from drug discovery are often lipophilic and poorly soluble. Medicinal chemists must improve solubility without reducing activity. Later in development, pharmaceutical scientists need to formulate a given　molecule for optimum absorbance. Success in these tasks calls for accurate　measured physicochemical properties like pKa, logP and solubility.

Solubility is an important parameter with relevance to drug absorption. Poor solubility can result in erratic　oral absorption and poor bioavailability. Of further interest, is the susceptibility of compounds to transform　from one solid form to another with different physical properties. In this study, two different polymorphs of a　proprietary Boehringer Ingelheim compound, BIX 011397 (polymorph III) and BIX 011398 (polymorph I)　were investigated by the CheqSol (Chasing Equilibrium Solubility, patent applied for) method for equilibrium　solubility measurement.1, 2 The method dissolves and partially reprecipitates ionizable compounds using a　GLpKa/D-PAS titration system that can repeatably cycle the solution between a supersaturated and　subsaturated state. Accurate solubility values are determined from the transition between the supersaturated solution (with solid precipitating) and the　subsaturated system (with solid redissolving). The　objective was to investigate the feasibility of detecting polymorphic conversions whilst performing these　equilibrium solubility studies. Comparisons were made to traditional shake-flask measurements, and solids　were characterized using TGA, DSC, microscopy and XRPD methods.

A multiwavelength spectrophotometric (WApH) titration method for determination of acid dissociation　constants (p Κa　values) of ionisable compounds developed previously was applied in the case of pyridine　derivatives of pharmaceutical interest. Specifically, UV absorption spectra of the drug solution are acquired in　the course of a pH-metric titration using an optical device based on a fibre optics dip probe, a light source and diode array detector. Target factor analysis was applied to deduce the p Κa　values from the spectral data　recorded at different pH. Using this technique, the p Κa　values of six pyridine derivatives were determined　successfully. It was demonstrated that the WApH technique in this case outperforms conventional pH-metric　methods with respect to the measurement of p Κa　values of the sparingly water soluble samples reported in this　study. 1999 Elsevier Science B.V. All rights reserved.

The apparent acid dissociation constants (psKa) of two water-insoluble drugs, ibuprofen and quinine, were　determined pH-metrically in acetonitrile–water, dimethylformamide–water, dimethylsulfoxide–water, 1,4-dioxane–　water, ethanol–water, ethylene glycol–water, methanol–water and tetrahydrofuran–water mixtures. A glass electrode　calibration procedure based on a four-parameter equation (pHaSpcHjH[H]jOH[OH]) was used to obtain　pH readings based on the concentration scale (pcH). We have called this four-parameter method the Four-Plus™　technique. The Yasuda–Shedlovsky extrapolation (psKalog [H2O]A:oB) was used to derive acid dissociation　constants in aqueous solution (pKa). It has been demonstrated that the pKa values extrapolated from such solvent–water mixtures are consistent with each other and with previously reported measurements. The suggested　method has also been applied with success to determine the pKa values of two pyridine derivatives of pharmaceutical　interest. © 1999 Elsevier Science B.V. All rights reserved.

Lipophilicity represents the affinity of a molecule or moiety for a lipophilic　environment. It is commonly measured by its distribution behavior in a　biphasic system, either liquid-liquid (e.g.,partition coefficient in octanol/　water) or by chromatographic methods [1]. Knowledge of lipophilicity is　used in a variety of methods that may predict absorption and other transport　properties of drug molecules in the human body.

CheqSol is a novel procedure for solubility measurements and stands for Chasing Equilibrium Solubility(www.cheqsol.com). The new method (patent applied for) provides rapid results (20 – 80 minutes) for kinetic and equilibrium solubility of organic acids, bases and ampholytes. Although many other methods have been described for the measurement of solubility, most of them will provide only kinetic or only intrinsic solubility data from one assay.

Variations in Coupled Water, Viscoelastic　Properties, and Film Thickness of a Mefp-1 Protein　Film during Adsorption and Cross-Linking: A　Quartz Crystal Microbalance with Dissipation Monitoring, Ellipsometry, and Surface Plasmon　Resonance Study

The frequency and energy dissipation change of a quartz crystal microbalance during moisture absorption was measured for films with thickness ranging from 3 to 205 nm. Evidence of the viscoelastic nature of the films was observed for films thicker than 90 nm through the frequency and energy dissipation changes. For sufficiently thin films (t < 40 nm), the frequency change could be effectively modeled as a simple increase in mass, as predicted by the Sauerbrey equation. The viscosity of the swollen films was independent of initial polymer film thickness (93-205 nm).

扫描电化学显微镜（Scanning Electrochemical Microscopy, SECM）现已发展成为一个具有权威性的仪器，它运用电化学原理成像或表面修饰。扫描电化学显微镜在很多领域都产生了巨大影响，诸如腐蚀，半导体刻蚀，金属沉积和生物材料表面形态的研究。 所有的扫描探针显微镜都是通过探头顶端所接触的表面进行测试，来获得检测信号，即通过探头顶端所接触的表面进行测试。在扫描电化学显微镜测试过程中，“超微电极”会靠近接触表面同时产生电活化物质；作为后端接触表面，它既有驱动电化学反应的作用又是“超微电极”与表面距离指示器。“超微电极”测量的反馈电流主要取决于“超微电极”到表面的距离以及表面电子转移的速度，常常用来监测“超微电极”的逼近方式。 如今，Nanonics研发出针对SECM的独特探针。这是建立在Nanonics微电极所特有的特殊专利：锥形玻璃“包裹”和悬臂技术的基础之上的；这些微电极可适用于所有Nanonics SPM/NSOM平台并具有独特的光学反馈。平台的突出特点是其光学友好性，能兼容包括常规拉曼在内的所有光学显微镜系统。能够从底部、顶部及侧面，从各个几何学角度进行光学测量。

This standard Q-Sense flow module is included with the E1 (one module) and E4 (four modules) instruments. Q-Sense flow modules are made of Aluminum and Titanium and the o-rings and sealing are Viton. More chemically resistant materials are available upon request. Liquid samples only contact Titanium and Viton during experimentation.

ChemiSens is proud to present the latest ChemiCall™ software module for advanced process design and evaluation. ProFind™ is the result of an extensive development together with leading expertise in the field of process development, process safety and process intensification and it integrates with the existing ChemiCall™ software for the ChemiSens™ Reaction Calorimeter systems. While lately, continuous reaction technology has undergone tremendous developments, semi-batch reactors will still in the future be dominating in the field of fine chemical production. However, new safer and more efficient operating strategies are requested and “process intensification” has become the latest buzzword in the industry.

Nanonics presents a novel, patented planar, folded-piezo, flexure scanner design that allows simultaneous lateral and axial sample scanning as well as coarse inertial positioning. The ultra-thin package permits the scanner to be incorporated into systems where conventional scan stages would be too bulky. This unique device, developed for Nanonics' near-field scanning optical microscope, is now available as a stand alone addition for all scanning applications.

esARC With all new software and hardware, but retaining the original features, the esARC upholds the tradition of this benchmark safety calorimeter whilst making it state-of-art. Already installed in 30 laboratories!

We present a method for combined far-field Raman imaging, topography analysis and near-field spectroscopy. Surfaceenhanced Raman spectra of Rhodamine 6G (R6G) deposited on silver nanoparticles were recorded using a bent fibre aperture-type near-field scanning optical microscope (NSOM) operated in illumination mode. Special measures were taken to enable optical normal-force detection for control of the tip–sample distance. Comparisons between far-field Raman images of R6G-covered Ag particle aggregates with topographic images recorded using atomic force microscopy (AFM) indicate saturation effects due to resonance excitation.