KF, DVS, low-RH handling, dissolution, and disintegration services connect water to stability, form, and product performance.
This decision-focused guide explains the scientific measurement basis, when to use it, its limitations, sample amount considerations, competing methods, FDA-facing concerns, and common mistakes.
KF measures water content selectively. DVS measures mass change as humidity changes, showing how quickly and how much water or solvent is absorbed or adsorbed. Low-RH and humidity-controlled handling protect samples whose physical state changes with water activity.
Use these methods for hygroscopicity, hydrate/anhydrate risk, amorphous-content and recrystallization studies, formulation water activity, packaging questions, low-RH sample handling, dissolution/disintegration support, and humidity-stability investigations.
KF can be complicated by insoluble samples, side reactions, volatile components, or non-water mass loss. DVS measures mass, not structure, so post-stress XRPD/Raman/IR or microscopy is needed to prove hydrate formation, crystallization, or morphology change.
DVS typically uses milligram-scale material, but exact amounts depend on pan, sensitivity, inhomogeneity, and repeat requirements. KF amount depends on expected water level and method format: coulometric, volumetric, or oven KF.
TGA, loss on drying, XRPD, Raman/IR, microscopy, DSC, solid-state NMR, and VT/VRH-PXRD all compete or complement water analysis depending on whether the question is quantity, phase identity, kinetics, or performance.
FDA cares that the water method distinguishes water from other volatiles, is specific and validated where used for release or stability, and is connected to form control, microbial risk, stability, packaging, or drug-product performance.
Common mistakes include treating TGA mass loss as water without confirmation, ignoring ambient humidity during sample transfer, using KF reagents incompatible with the sample, and running DVS without structural analysis of post-stress material.
Triclinic uses water-vapor and moisture analysis to evaluate real-world risks from hygroscopicity, hydrate formation, desolvation, sorption, desorption, and water-driven solid-form or performance changes. Applications include DVS and Karl Fischer support for stability, packaging, storage, process exposure, lot comparability, amorphous-material behavior, and investigations where water content or humidity history changes material performance.
The table below lists the specific platforms, brands, models, software, detectors, and capability notes relevant to this service area.
| Instrument or platform | Brand, model, software, or detector | Additional capabilities and use |
|---|---|---|
| Karl Fischer water determination | Mettler Toledo V20 and C20 systems | Volumetric and coulometric KF water-content analysis for solids, liquids, and formulations. |
| Oven KF and insoluble-sample support | Mettler Toledo KF systems with drying-oven configuration | Water determination for insoluble materials or samples that react with conventional KF reagents. |
| Dynamic vapor sorption | TA Instruments Q5000 DVS systems with Thermal Advantage for Q Series v.5.4.0 | Sorption/desorption isotherms, kinetic water uptake, hygroscopicity, amorphous-content support, and moisture-induced change investigations. |
| Low-RH handling | Low-relative-humidity handling capability | Humidity-sensitive sample preparation, transfer, and analysis support where ambient water exposure may alter phase or performance. |
| Dissolution support | VanKel VF750D with UV/VIS or HPLC detection | Drug-release and dissolution profiles where water interaction and release behavior are linked. |
| Disintegration testing | Testerion DT2 | Tablet/capsule disintegration testing under standardized conditions. |
| Humidity-controlled XRPD support | Anton Paar CHCplus Cryo and Humidity Chamber on PXRD system | Structural confirmation of hydrate/anhydrate conversion, recrystallization, or phase changes under defined RH/temperature conditions. |
This example connects water analysis to solid-form risk. The legacy water-analysis page describes KF, DVS, low-relative-humidity handling, dissolution, and disintegration services for questions involving water content, water uptake, and aqueous performance. A humidity-controlled XRPD example is useful because water does not just change mass; it can drive hydrate formation, dehydration, crystallization, or other phase changes that affect stability and performance.
These examples include technical resources, regulatory guidances, or literature relevant to the technique. Download buttons are placed at the bottom-left of each example.
Author: Triclinic Labs
Publication date: 2023
Abstract: Application note showing how VT/VRH-PXRD follows theophylline phase transitions under controlled humidity and temperature. The example supports using non-ambient diffraction to evaluate hydrates, anhydrates, stability boundaries, and process-relevant phase transformations.
Author: Triclinic Labs
Publication date: 2025
Abstract: This application note uses modulated DSC to quantify amorphous content in crystalline API by evaluating heat-capacity change at the glass transition, illustrating how thermal methods can support low-level amorphous-content control and stability interpretation.
Author: International Council for Harmonisation / FDA
Publication date: 2024
Abstract: FDA notes that ICH Q2(R2) and Q14 describe validation and development principles for analytical procedures used to assess drug substance and drug product quality. These guidances frame FDA expectations for specificity, accuracy, precision, range, robustness, lifecycle management, and fit-for-purpose method evidence.
Use this technique when its evidence better matches the sample, matrix, or development decision.
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Tell Triclinic what sample you have, what decision the data must support, what prior data are available, and whether cGMP, release, validation, or regulatory documentation is required.
