Moisture, analysis

Photometric Moisture Analysis TTis analyzer reqiiires a light source, a filter wheel rotated by a synchronous motor, a sample cell, a detector to measure the light transmitted, and associated electronics. Water has two absorption bands in the near infrared region at 1400 and 1900 nm. This analyzer can measure moisture in liquid or gaseous samples at levels from 5 ppm up to 100 percent, depending on other chemical species in the sample. Response time is less than 1 s, and samples can be run up to 300°C and 400 psig. 

Sample for Moisture Analysis consists of approx 50g reserved from 4.3.2.1... 

The analytical method for moisture determination must be validated before use during process validation studies. There are numerous techniques for moisture analysis that range from physical methods, such as loss on drying, to chemical methods, such as Karl Fisher titration. A comparative review of the conventional techniques are presented in an overview [32], The measurement of residual moisture is lyophilized pharmaceuticals by near-infrared (NIR) spectroscopy has recently been expanded [33]. 

Once the baseline data for heat distribution are established, the combination of in-process moisture analysis (of the load being dried) and heat or airflow distribution (for a loaded oven) will help the technologist understand the drying process for a product. In addition, other information learned will include the moisture level in the dried granulation can be reached without exposing the material to excess heat. This relationship will help QA evaluate the process during validation as well as audit the process if process deviations should be encountered. 

To determine the total moisture, either an analysis sample can be prepared from the moisture sample, or the regular analysis sample can be used for this purpose, provided that the moisture analysis is performed on the analysis sample within a prescribed time after the air-dry sample is prepared. When separate analysis samples are used for moisture and for the other determinations that are... 

Table 1.15.2 Moisture analysis of FM257/2, V9032 stoppers (Helvoet Pharma, Pennsauken, N), USA). All stoppers were autoclaved for 16 min, vacuum dried for 30 min and oven dried at 100 °C for the specified time (Table 4 from [1.180])... 

Oxide Sensors Aluminum oxide can be used as a sensor for moisture analysis. A conductivity call has one electrode node of aluminum,... 

Examination of product control charts is most useful in trying to distinguish between process-related or non-process-related causes.Trend analysis of key production parameters and attributes could assist in localizing a possible cause of the OOS. For example, if the potency of the product has been trending higher than usual for the last few batches produced (and the OOS resulted from an upper limit failure), this could be indicative of such causations as inaccurate moisture analysis or operator compensation error, error in the batch record, weighing error due to balance or scale bias, change in excipient purity which could impact functional characteristics or failure to maintain and/or calibrate apiece of equipment. 

Since 5 g (wet weight) samples had been taken at each aw, standardized concentrations relative to the initial dry weight of the sample were determined. Moisture analysis was accomplished using the GC method of Reineocius and Addis (25). 

In essence, the test battery should include XRPD to characterize crystallinity of excipients, moisture analysis to confirm crystallinity and hydration state of excipients, bulk density to ensure reproducibility in the blending process, and particle size distribution to ensure consistent mixing and compaction of powder blends. Often three-point PSD limits are needed for excipients. Also, morphic forms of excipients should be clearly specified and controlled as changes may impact powder flow and compactibility of blends. XRPD, DSC, SEM, and FTIR spectroscopy techniques may often be applied to characterize and control polymorphic and hydrate composition critical to the function of the excipients. Additionally, moisture sorption studies, Raman mapping, surface area analysis, particle size analysis, and KF analysis may show whether excipients possess the desired polymorphic state and whether significant amounts of amorphous components are present. Together, these studies will ensure lotto-lot consistency in the physical properties that assure flow, compaction, minimal segregation, and compunction ability of excipients used in low-dose formulations. 

Betteridge, D., Mackison, R., Mottershead, C.M., Taylor, A.F. and Wade, A.P. (1988) Development of an expert system for the selection of sample points for moisture analysis. Anal. Chem., 60, 1534-1539. 

J. E. Jewell, R. Workman, and L. D. Zelenznick, Moisture analysis of lyophilized allergenic extracts. Dev. Biol. Stand. 86 182-189 (1977). 

Ideally, cottonseed should be stored at a moisture content of less than 10% (49). Dehulled seeds should contain no more than 9% moisture and 1% FFA (109). Prior to storage, cottonseeds must be sampled for moisture analysis. The American Oil Chemists Society (AOCS) method Aa 3-38 specifically describes a procedure for... 

Actual drug content of the samples was determined by HPLC water content was determined by Karl Fischer moisture analysis. For prediction of the drug content, three NIR calibrations using MLR were developed. 

One of the keys for generating reproducible data is to consider a system s lower detection limit and the upper limits for linear detector response (Beer s law). For instance, coulometric moisture analysis is accurate for samples containing 10 (Xg of H20. Injection of a particularly dry sample may deliver <10 xg of H20,in which case the amount of water measured may not be accurate. Similarly, injecting a dilute sample aliquot may not allow the detection of an impurity present at low levels, so a more concentrated sample preparation may be required. The analysis of a sample preparation more concentrated than those routinely prepared may give detector area count responses beyond the linear response for that compound, making the calculated concentration lower than the true concentration. The injection of a highly concentrated sample may also saturate the detector... 

Moisture. Control of moisture has become a major challenge as part of the contamination control picture. Mil-Std-883C, Method 1018.2, recognizes this and has established mass spectrometry as one of the methods found suitable for moisture analysis in packaged devices with internal volumes of 10 to 800 microliters. 

Figure 2. Block Diagram of inlet systems for the FTMS including custom moisture analysis fixture.

Figure 4. Component holder for internal moisture analysis of sealed devices.

Figure 5. Three volume generator for moisture analysis calibration.

Application of the FTMS to microelectronic laboratory service has proven to be very successful. Instrument stability and resolution are unmatched by conventional instruments. In moisture analysis, comparison of quadrupole and magnetic sector Instruments with FTMS, has, in addition, shown higher sample through-put and data consistency for both known atmospheres and device lot samples. 

A modern-day petroleum refinery is a complex chemical operation that involves numerous separations and chemical processing steps. Today virtually all the chemical analysis equipment found in the research laboratory is also used in the refinery or an online basis is often coupled to a control circuit to monitor product quality and make the necessary immediate adjustment in process conditions required to meet product specifications. While the online gas chromatograph is the most widely used instrument, infrared spectrometers, mass spectrometers, pH indicators, new infrared spectrometers with chemometric capability and moisture analysis based in solid-state conductors are not found in every refinery in the country. Until the 1970s, samples of most process streams in the refinery were taken at periodic intervals during the day and adjustments were made after the research was received from the refinery s analytical lab. This process was followed by the installation of online analysis equipment that sounded alarms, and the equipment operators took appropriate action. Today most operations are on computer control and the information received from online analytical equipment is processed almost continuously and controls make the required changes. An alarm may still sound and the equipment operator still responds, but usually the problem has already been corrected. 

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