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Automated techniques and philosophies, which have become increasingly important in modern laboratories, are not traditionally covered in undergraduate chemistry curricula. To this end, we have been incorporating automated sample preparation methods using standard robotic workstations in our undergraduate analytical chemistry laboratory. Using a Benchmate™ II Workstation, an automated method has been developed and implemented for the solid phase extraction of capsaicins from commercial hot pepper sauces prior to liquid chromatographic analysis. This paper reports on pedagogical aspects of incorporating automation into the undergraduate curriculum as well as results obtained for manual and automated extractions conducted by students.

The advantages of using a new automated system, the Hydra-Plus-One System equipped with 96 or 384 precision glass syringes and a non-contact microsolenoid dispenser, in setting up high-throughput low-volume sequencing reactions and PCR are described. Using the syringe-based dispenser, which is the Hydra-PP part of this system, wet dispenses of as small as 100 nL with CVs of less than 10% can be accomplished. The single-channel, non-contact microsolenoid dispenser part of the system can dispense samples as low as 100 nL (with CVs of less than 10%) at a speed of 58s per 96 dispenses into any plate format (SBS footprint). The advantages associated with the use of the Hydra-Plus-One System for setting up PCR and sequencing reactions are high precision at nanoliter-dispense range; speed; and minimal waste of precious and expensive samples. The single-channel dispenser eliminates the dead volume associated with aspirating from reservoirs or troughs and thereby reduces sample waste. In addition, virtually all material can be recovered from the dispenser. Finally, non-contact dispensing enables distribution of sample into wells without any in-between-dispenses washing requirements.
An optical wave-guide based two-color capillary electrophoresis laser induced fluorescence (CE-LIF) instrument is described. The wave-guide based approach allows for on column excitation and detection with two-color discrimination. The instrument is designed to allow either electrokinetic or hydrodynamic injections. In its present configuration, the attainable limit of detection (LOD, S/N = 3) was 50 × 10−21 moles of fluorescein with a 488-nm excitation source. This study was designed to test the instrument design for applications in protein analyses. Fluorescent dyes with two different wavelengths were simultaneously separated and detected as were complexes formed by labeled antibodies to NF'B p65 and cdc2p34. Quantification of both proteins in THP-1 cell lysates performed using this approach illustrates a rapid screening application of this instrument.
High-resolution ultrasonic spectroscopy is a novel technique with enormous potential for analysis of a wide range of samples and processes. This technique is based on precision measurements of velocity and attenuation of acoustical waves at high frequencies propagating through materials. It allows fast at/on line measurements analysis of formulation consistency (composition, structure) of raw materials, ingredients and intermediates, process impurity analysis, particle sizing, batch to batch variation, stability assessment etc in pharmaceutical industry. The technology can be used for static fingerprint measurements or for dynamic analysis of systems. Optical transparency is not required as ultrasonic waves propagate through opaque samples. The analysis is fast and non-destructive. High-resolution ultrasonic spectrometers were developed, patented and brought to the market by Ultrasonic Scientific Ltd. and recognised with various international awards. These instruments require small sample volumes, down to 0.03 ml, and give excellent resolution. They can be used for the analysis of composition, aggregation, particle sizing, gelation, micellisation, crystallisation, sedimentation, enzymatic activity, conformational transitions in polymers, biopolymer-ligand binding and antigen-antibody interactions, etc. This article describes main features of High-Resolution Ultrasonic Spectroscopy and area of applications of new high-resolution HR-US series of ultrasonic spectrometers.
Several applications are illustrated including the monitoring of denaturation and aggregation of proteins in antibody solution, the measurements of the particle size in emulsions, precipitation in synthetic blood substitutes and crystallisation.
We describe a reagent system and robotic protocol for the isolation of highly purified plasmid DNA from cultured cells. The method is based on the Wizard® MagneSil™ Plasmid Purification System, which purifies sequencing-grade plasmid DNA. Two modifications to the sequencing-grade system were made to create the Wizard MagneSil Tfx™ System. This system provides lower endotoxin and other contaminant levels, giving higher quality plasmid for transfection applications. The Wizard MagneSil Tfx™ System uses MagneSil™ Paramagnetic Particles (PMPs) to clear lysate and bind plasmid, eliminating the need for filtration devices. The endotoxin removal step uses MagneSil™ (PMPs) and a guanidine/isopropanol wash to remove RNA and protein. One 96-well plate may be processed in 45 minutes on the Beckman Biomek® FX robotic workstation. We provide data showing DNA yield, contaminant levels, and transfection efficiency for 5 commonly used cell lines. Comparisons with other systems are also shown.
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