蛋白质依靠短程相互作用识别配体蛋白进而行使生物学功能，其相互作用界面仅占据蛋白质总表面积的一部分．因此，蛋白质与配体蛋白需要形成一系列遭遇复合物系综结构来减少构象搜索空间以加快结合速度．由于遭遇复合物在溶液体系中存在时间短、丰度低，因而很难被传统结构生物学技术捕捉到．本文选用组氨酸磷酸载体蛋白（HPr）和酶II（EIIA^Glc）复合物为研究体系，采用顺磁弛豫增强（Paramagnetic Relaxation Enhancement，PRE）技术对遭遇复合物的系综结构及动力学性质进行表征，并用分子动力学模拟方法对实验结果进行验证，发现HPr在溶液体系中首先与EIIA^Glc在3个方向上形成遭遇复合物，进而促进特异性复合物的形成．该方法不仅能够在溶液体系中观察遭遇复合物系综结构，还有望应用于生物大分子领域，揭示蛋白质在复杂生理网络中的相互作用机制及动力学行为．

本研究采用液相色谱-二极管阵列检测器-固相萃取-核磁共振/质谱（LC-DAD-SPE-NMR/MS）联用技术，对卡巴他赛注射液中一个含量约为0.3%~0.4%的未知降解杂质完成化学结构解析. 卡巴他赛注射液中高含量的辅料吐温-80与该杂质在液相色谱分析中不能完全分离，直接制备高纯度杂质难度较大，因此难以采用先分离-后鉴定的传统策略鉴定该杂质. 本研究采用自动化的LC-DAD-SPE-NMR/MS联用技术，通过对萃取物溶液进行NMR谱详细分析，提取出降解杂质中氢-氢、氢-碳原子间相关信息，得到原子化学位移及连接关系，成功排除吐温-80谱峰的干扰，最终鉴定降解杂质为卡巴他赛中紫杉烷母核重排后的产物. 整个实验在48 h之内完成，并以混合物分析思路完成降解杂质结构解析. 本研究是LC-DAD-SPE-NMR联用技术在微量药物杂质分析领域的一次成功应用实例，为新药研究中杂质结构解析提供了新思路.

Nuclear Magnetic Resonance (NMR) has been widely employed to assess diverse features of glycan-protein molecular recognition events. Different types of qualitative and quantitative information at different degrees of resolution and complexity can be extracted from the proper application of the available NMR-techniques. In fact, affinity, structural, kinetic, conformational, and dynamic characteristics of the binding process are available. Nevertheless, except in particular cases, the affinity of lectin-sugar interactions is weak, mostly at the low mM range. This feature is overcome in biological processes by using multivalency, thus augmenting the strength of the binding. However, the application of NMR methods to monitor multivalent lectin-glycan interactions is intrinsically challenging. It is well known that when large macromolecular complexes are formed, the NMR signals disappear from the NMR spectrum, due to the existence of fast transverse relaxation, related to the large size and exchange features. Indeed, at the heart of the molecular recognition event, the associated free-bound chemical exchange process for both partners takes place in a particular timescale. Thus, these factors have to be considered and overcome. In this review article, we have distinguished, in a subjective manner, the existence of multivalent presentations in the glycan or in the lectin. From the glycan perspective, we have also considered whether multiple epitopes of a given ligand are presented in the same linear chain of a saccharide (, poly-LacNAc oligosaccharides) or decorating different arms of a multiantennae scaffold, either natural (as in multiantennae -glycans) or synthetic (of dendrimer or polymer nature). From the lectin perspective, the presence of an individual binding site at every monomer of a multimeric lectin may also have key consequences for the binding event at different levels of complexity.

It is widely held that the spatial resolution achievable by NMR microscopic imaging is limited in biological systems by diffusion to approximately 1-5 microns. However, these estimates were developed for specific imaging techniques and represent practical rather than fundamental limits. NMR imaging is limited by the signal-to-noise ratio (SNR). Diffusion effects on spatial resolution can be made arbitrarily small in principle by increasing the gradient strength. The exponential signal attenuation from random spin motion in a gradient, however, will reduce the signal far below the noise level when the voxel size is reduced much below 5 microns. Two factors can be optimized to improve the SNR: (1) the inductive linkage between microscopic samples and the detection apparatus and (2) the temperature of the rf probe. In this work, the filling factor was optimized using inductors with diameters less than 1 mm. It is furthermore shown that probe circuit cooling results in significant improvements in SNR, whereas cooling of the preamplifier is of little value when proper noise matching between the resonant circuit and preamplifier is accomplished. Using three-dimensional Fourier imaging techniques, we have obtained images of single-cell organisms with spatial resolution of approximately 6 microns. Practical limitations include mechanical stability of the apparatus, thermal shielding between the sample and probe, and the magnetic susceptibility of the sample.

The low frequency plateau in the frequency response of an untuned micro-resonator permits broadband radio-frequency reception, albeit at the expense of optimal signal-to-noise ratio for a particular nucleus. In this contribution we determine useful figures of merit for broadband micro-coils, and thereby explore the parametric design space towards acceptable simultaneous excitation and reception of a microfluidic sample over a wide frequency band ranging from C to H, i.e., 125-500 MHz in an 11.74 T magnet. The detector achieves 37% of the performance of a comparably sized, tuned and matched resonator, and a linewidth of 17 ppb using standard magnet shims. The use of broadband detectors circumvents numerous difficulties introduced by multi-resonant RF detector circuits, including sample loading effects on matching, channel isolation, and field distortion.

We have developed an easy to construct, non-resonant wideband NMR probe. The probe is of the saddle coil geometry and is designed such that the coil itself forms a transmission line. The probe thus requires no tuning or matching elements. We use the probe with a spectrometer whose duplexer circuitry employs a simple RF switch instead of the more common lambda/4 lines, so the entire probe and spectrometer perform in an essentially frequency-independent manner. Despite being designed with electro- and magnetostatic formulas, the probe performs well at frequencies up to 150 MHz and beyond. We expect that with additional design effort, the probe could be modified for use at significantly higher frequencies. Because our construction method relies on commercial circuit fabrication techniques, identical probes can be easily and accurately produced.