Method transfer example

For those waste streams that can impact public health or the environment (if mismanaged), provide a summary of the treatment and disposal methods (for example, solvents are incinerated or recycled, lab wastes are incinerated) used to manage them and identify the on-site or off-site facilities used. Is the disposal of the waste adequately documented (for example, retention of manifests, bills of lading or transfer notes) ... 

Measurement of the absorption rate of carbon dioxide in aqueous solutions of sodium hydroxide has been used in some of the more recent work on mass-transfer rate in gas-liquid dispersions (D6, N3, R4, R5, V5, W2, W4, Y3). Although this absorption has a disadvantage because of the high solubility of C02 as compared to 02, it has several advantages over the sulfite-oxidation method. For example, it is relatively insensitive to impurities, and the physical properties of the liquid can be altered by the addition of other liquids without appreciably affecting the chemical kinetics. Yoshida and... 

On the other hand, the enhanced heat dissipation from the small volume of reagent into the relatively large volume of reactor body can be disadvantageous where the sample within micro-channels has to be heated up. In a conventional heating method, for example using a thermal bath or oven, the reactor body needs to be heated up first and then the heat is transferred by thermal conduction into the sample in the micro-channels. In this case, only a very small portion of heat is ef-... 

Some LC/MS users adhere to isocratic separation because of the myths around gradient elution (it is complex to develop and transfer between instruments and laboratories, it is inherently slower than isocratic methods because of re-equilibration, and other reasons summarized by Carr and Schelling6). A researcher may have a very good reason to use an isocratic method, for example, for a well defined mixture containing only a few compounds. The isocratic method would certainly not be useful in an open access LC/MS system processing varying samples from injection to injection. 

For any new excipients, APIs or drug products (where new does not necessarily mean novel, but new to the receiving site) there are additional testing criteria, e.g. supplier audits, third-party contract laboratory audits, analytical method transfers, sample management/tracking, etc. For those key excipients, where there is on-site historical experience, it still behoves both parties to check whether the local grade/supplier used by the CMO is equivalent to that used by the supplier (Worsham, 2010). There are many examples of differences in excipient physical properties, e.g. particle size, which have been attributed to different excipient sources that could ultimately impact on the performance of those excipients in formulated products (Frattini and Simioni, 1984 Dansereau and Peck, 1987 Phadke et al., 1994 Lin and Peck, 1994). 

Experience with CE method transfer in the biotech/pharmaceutical industry over the past 10—20 years has demonstrated that training is a key element that requires special attention for CE methods. A training video with troubleshooting examples can be very useful. Tips and hints should also be shared during the method transfer process. Other key elements for a successful transfer include selection of the proper testing strategy and assay acceptance criteria. 

It is evident that the values of the transfer constants are dependent on the nature both of the attacking radicals and of the transfer agent itself, and that similar effects should be expected during the synthesis of graft copolymers by chain transfer methods. For example, with respect to toluene the chain transfer constant is a little greater for methyl methacrylate radicals than for styrene radicals on the contrary, with respect to halogenated solvents (CC14) the polystyrene radical is much more effective in the removal of a chlorine atom. Vinyl acetate chains are far more effective than either of the other two polymer radicals. 

The term method transfer does not formally appear in the current FDA regulations or guidance documents. The ICH requirement of reproducibility , however, is intended to demonstrate the precision of analyses between laboratories. As a successful part of the total method validation, this ana-lyst-to-analyst comparison at different laboratory sites serves to prove the method validity. Also, this portion of validation can occur during the original validation experiments or at a future date. As an example, a method is developed in an analytical R D group to be eventually transferred to QC labs, production facilities, or contract laboratories worldwide. These reproducibility experiments would be performed as method-transfer exercises. 

The process of method transfer must follow a method-transfer protocol which defines the experiments and acceptance criteria necessary to demonstrate the analysts proficiency, equipment s suitability, and true ruggedness of the analytical method. If we assume that any quality analytical laboratory has proficient analysts who operate suitable equipment, then the method transfer stands as an ongoing means to substantiate the suitability of the original method validation. Example 5 contains an example of a method-transfer protocol for a chromatographic procedure. 

Some new and attractive methods, for example eliminations under phase-transfer conditions and couplings under the influence of zero-valent palladium compounds, have been included. 

More recently double stranded DNA-binding dyes, (e.g., SYBR Green), have been introduced (Giulietti et al. 2001) which removed the need for an expensive, specific probe to be designed. Other sophisticated tools have been developed to work in conjunction with the Taqman method, for example molecular beacons, scorpions and hybridisation probes. These techniques rely on the FRET (Fluorescence Resonance Energy Transfer) principle but do not require the nuclease activity of the Taq polymerase. The different real-time... 

The current detailed understanding of photo-induced electron transfer processes has been advanced dramatically by the development of modern spectroscopic methods. For example, the application of time-resolved optical spectroscopy has developed from modest beginnings (flash-phyotolysis with millisecond resolution) [108,109] to the current state of the art, where laser spectroscopy with nanosecond resolution [110-113] must be considered routine, and where picosecond [114-116] or even femtosecond resolution [117] is no longer uncommon. Other spectroscopic techniques that have been applied to the study of electron transfer processes include time-resolved Raman spectroscopy [118], (time resolved) electron spin... 

The Re(CO)s (3) radical, which may also be generated by several other methods, for example, deposition of Re atoms on a CO matrix at 10 K or Pulse Radiolysis of ReBr(CO)s in ethanol, has the theoretically predicted square-pyramidal structure that is maintained in solution at room temperature. Reactions where (3) may play a crucial role after photochemical generation from (1) include halogen abstraction, disproportionation, and electron transfer to an electron acceptor (EA) (Scheme 2). 

Other considerations include differences in dwell volumes from the different HPLC systems. The dwell volume should be determined for all the systems in the laboratory and based on these determinations, this should be factored into the calculation of the equilibration time. For example, if the maximum dwell volume of all the systems in a particular laboratory to which the method is transferred to is 2mL and you are running on an instrument at 1 mL/min that has a dwell volume of 1 mL, then you should add an extra minute of equilibration time. This becomes extremely important during method transfers where the instruments in the receiving laboratory may be different. 

Since the aim of the protocol is to ensure the mitigation of problems, the essential elements of the protocol consists of sections that include (a) an Introduction, (b) treatment and disposition of data, (c) types of methods being transferred, (d) materials, reference standards, and reagents being used, (e) recommended type of equipment, (f) sample handling, (g) predetermined acceptance criteria, and (h) an Acknowledgment section. An example of a typical table of contents (TOC) of an analytical methods transfer protocol is discussed in Table 16-2. 

In cases where a general QL is required, as in pharmaceutical analysis, it is essential to define a realistic QL (or DL) for the analytical procedure, independently from the equipment used, because this limit has important consequences (e.g., for the consistent reporting of impurities or for method transfer). They may be derived by taking QL (or DL) from various instruments into account ( intermediate QL, during the development process) or can be defined taking the requirements of the control test (specification limits imposed by toxicology or by a qualified impurity profile) into consideration. For example, a QL which... 

HSQC) or heteronuclear multiple quantum correlation (HMQC). The combined experiments such as 2D HSQC(HMQC)-TOCSY experiments are powerful tools for the assignment of the 13C and 11 resonances belonging to the same sugar residue providing enhanced dispersion of TOCSY correlations in the carbon dimension. More recendy, different carbon multiplicity editing methods, for example, DEPT (distortionless enhanced polarization transfer)-HMQC and E-HSQC, have been developed to reduce the complexity of proton-carbon correlation spectra and to enhance the resolution by narrowing the applied spectral window.11... 

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