BOC Sciences provides integrated polymorph screening services for pharmaceutical compounds, intermediates, specialty chemicals, and other crystalline materials. Our scientists combine experimental crystallization, orthogonal solid-state analysis, phase-conversion studies, and physicochemical testing to map accessible forms and support evidence-based crystal-form decisions.
Polymorph screening is the systematic search for all solid forms of a molecule, including crystalline polymorphs, hydrates, solvates, amorphous phases and co-crystals. Because different forms of the same molecule can show very different solubility, dissolution rate, physical and chemical stability, hygroscopicity, mechanical behavior and processability, choosing the right form early is one of the most important decisions in drug and specialty-chemical development. A poorly selected form can lead to low bioavailability, unexpected phase conversion during storage, difficult scale-up or manufacturing variability. By mapping the full solid-form landscape at the start of a project, BOC Sciences helps clients lock in a thermodynamically stable, application-compatible form and avoid costly surprises later. Our approach is designed for drug-development scientists, formulation specialists and project managers who need reliable, decision-ready solid-form data.
BOC Sciences screens for pure anhydrous crystal forms that contain no solvent or water in the lattice, targeting the thermally stable, low-hygroscopicity forms preferred for long-term handling and storage.
We screen for water-containing crystal forms and assess water-activity-dependent behavior, reversible dehydration and the risk of hydrate formation during processing or storage.
BOC Sciences identifies non-aqueous solvates and evaluates residual-solvent content and phase behavior to help clients avoid solvate formation that could complicate downstream processing.
For molecules where the thermodynamically stable form has poor solubility, we explore kinetically accessible metastable forms that may offer a dissolution advantage while remaining practically manageable.
We assemble novel multicomponent crystalline phases with co-crystal formers to improve solubility, stability and mechanical properties while opening new intellectual-property space.
For ionizable compounds, BOC Sciences combines salt formation with polymorph screening to optimize the synergy between counter-ion selection and crystal-form behavior.
BOC Sciences helps research teams move from molecular structure and solubility constraints to a designed solvent matrix, controlled crystallization, orthogonal characterization and a decision-ready solid-form recommendation.
BOC Sciences selects complementary tests according to the compound, the forms observed during screening, available sample quantity, and the decision the client needs to make.
| Assessment Area | Representative Methods | Core Data |
| Crystal Form Identification and Structural Characterization | XRPD, single-crystal XRD, Raman spectroscopy, FTIR analysis, and solid-state NMR when applicable. | Diffraction peak positions and intensities, unit-cell and packing information, vibrational shifts, hydrogen-bonding changes, and local molecular environments. |
| Thermal Behavior and Phase Transition Analysis | DSC testing, TGA testing, combined thermal analysis, hot-stage microscopy, and isothermal microcalorimetry when justified. | Melting and transition temperatures, enthalpy changes, glass transition, mass-loss steps, decomposition onset, and visible changes during heating. |
| Moisture Sorption and Solvent Interaction Analysis | DVS or controlled-humidity studies, Karl Fischer titration, headspace GC testing, water-activity measurement, and XRPD before and after exposure. | Sorption and desorption profiles, water content, solvent content, hysteresis, conversion humidity, and phase identity after conditioning. |
| Solubility, Dissolution and Phase Equilibrium Testing | Equilibrium and intrinsic solubility, dissolution testing, slurry competition, temperature-dependent solubility, supersaturation profiling, and residual-solid XRPD. | Concentration at equilibrium, dissolution rate, induction time, metastable-zone width, recovered solid form, and temperature-solubility relationships. |
| Powder and Mechanical Property Characterization | Particle size distribution testing, BET surface area, microscopy, true and bulk density, powder-flow measurements, compaction, and mechanical property analysis. | D10, D50, D90, surface area, morphology, density, flow indices, hardness, elastic response, and compaction behavior. |
| Chemical Purity and Solid-State Stability Testing | HPLC testing, purity determination, chiral analysis when relevant, controlled temperature-humidity-light stability studies, and periodic XRPD or spectroscopy. | Assay response, impurity profile, enantiomeric composition, form identity, amorphous content, and changes after defined stress exposure. |
| Form Interconversion and Phase Diagram Studies | Temperature-humidity mapping, solvent-temperature mapping, water-activity slurries, competitive slurries, and in situ or time-resolved Raman/XRPD monitoring. | Stable-form regions, transition boundaries, conversion direction, conversion rate, solvent dependence, and kinetic persistence. |
The final data package can include a form inventory, preparation history, analytical comparison matrix, phase relationships, stability ranking supported by multiple experiments, recommended form-selection rationale, potential conversion pathways, and proposed follow-up studies. Conclusions are scaled to the evidence generated rather than inferred from a single instrument result.
Tell us whether your priority is form discovery, hydrate or solvate clarification, stability ranking, property comparison, crystallization troubleshooting, or confirmation of a suspected new phase. Our scientists will select the smallest defensible set of experiments needed to answer that question.
BOC Sciences reviews the molecular structure, ionization behavior, available quantity, synthesis and solvent history, known forms, current process, and project goal. The starting material is then assessed by suitable identity, purity, XRPD, thermal, and moisture-related methods to establish a reliable baseline.
A condition matrix is designed around solvent diversity, compound solubility, crystallization driving force, temperature range, water activity, cooling or evaporation rate, antisolvent ratio, agitation, seeding, and mechanical input. The design may be staged so that early form hits guide later experiments.
Screening experiments are executed at an appropriate scale, and solids are isolated using condition-matched filtration, centrifugation, evaporation, or drying. XRPD provides the primary comparison, while thermal and spectroscopic data help classify new patterns as anhydrates, hydrates, solvates, cocrystals, salts, or amorphous materials.
Distinct forms are confirmed, reproduced when necessary, and compared through targeted stability, solubility, moisture, interconversion, and particle-property studies. Clients receive an organized report linking each form to its preparation conditions, analytical evidence, phase relationships, performance attributes, and recommended next experiments.
Early projects may have only tens to hundreds of milligrams available, while poorly soluble compounds restrict conventional crystallization choices. BOC Sciences uses microscale solubility mapping, miniaturized crystallization, staged screening, solvent-mixture design, and shared analytical aliquots to increase information per unit of material. Conditions are prioritized by chemical diversity and mechanistic value instead of repeating similar solvents without a clear reason.
Oiling, glass formation, and poorly ordered solids may arise when supersaturation develops too quickly, molecular mobility is low, or impurities inhibit nucleation. We adjust concentration, solvent composition, cooling profile, antisolvent addition, agitation, hold time, seeding, and drying method. Temperature cycling, slurry aging, vapor diffusion, or mechanical approaches may be introduced to encourage ordered nucleation and recover solids suitable for characterization.
Closely related phases can produce overlapping diffraction peaks, while partial desolvation or dehydration may create mixtures during sample preparation. BOC Sciences combines XRPD with DSC, TGA, spectroscopy, microscopy, water or solvent quantification, and controlled reconditioning. Targeted recrystallization, seeding, and selective slurry conversion can enrich individual phases so that their identities and relationships are interpreted with greater confidence.
A form that appears stable in a dry vial may convert in contact with water, solvent, heat, or another polymorph. We construct targeted conversion studies using humidity exposure, water-activity slurries, solvent slurries, temperature cycling, competitive seeding, and time-resolved analysis. These experiments clarify transformation direction, likely driving forces, kinetic persistence, and the conditions that should be avoided or controlled in later process work.
Work with BOC Sciences to connect crystallization conditions, phase identity, thermal behavior, moisture response, solubility, particle properties, and interconversion evidence in one structured polymorph screening program.
Our team connects experimental crystallization with structure characterization, thermal analysis, spectroscopy, solution behavior, and phase-conversion studies. This integrated approach reduces gaps between form discovery and form evaluation and helps clients understand why a phase formed, how it can be reproduced, and where it may convert.
A limited-material discovery screen should not look like a broad confirmatory program. BOC Sciences adjusts experiment count, condition diversity, analytical depth, and follow-up testing to the available material and decision context. Programs can begin with rapid risk identification and expand into form reproduction, phase mapping, property comparison, and pre-formulation screening as evidence develops.
Diffraction identifies differences in long-range order, but interpretation is stronger when supported by thermal, spectroscopic, moisture, solvent-content, solubility, and conversion data. We select complementary techniques according to the question and clearly distinguish direct observations from scientific inference, giving clients a traceable basis for comparing solid forms.
Some compounds do not yield a suitable neutral crystalline form under the first screen. BOC Sciences can extend the investigation to salts, cocrystals, amorphous materials, hydrates, solvates, particle engineering, or formulation-oriented approaches. This flexibility helps the project follow experimental evidence instead of forcing every molecule into a single solid-form strategy.
Client Needs: A formulation team at a development-stage company was advancing a poorly soluble BCS Class II-like small molecule and needed a polymorph with improved dissolution for an early oral prototype. Their as-received crystalline material showed low intrinsic solubility and slow dissolution in simulated gastric buffer.
Challenges: The molecule crystallized poorly, tended to oil out in several common solvents, and the initially isolated form converted to a less soluble phase during slurry experiments. Distinguishing the higher-energy forms from mixtures proved difficult by XRPD alone.
Solution: We ran 72 miniaturized crystallization conditions across solvent, anti-solvent and cooling modes, then ranked the isolated solids by XRPD and DSC/TGA. Slurry experiments in three aqueous buffers identified the thermodynamically stable form, while a metastable form with roughly 1.8-fold higher intrinsic solubility was captured under controlled anti-solvent addition. Single-crystal growth and Raman monitoring confirmed the assignment, and the metastable form was advanced for prototype evaluation.
Outcome: The client received a clean metastable-polymorph batch with improved dissolution, a clear stability-risk note and a phase-diagram summary to guide process control.
Client Needs: A development program for a crystalline intermediate needed to understand whether the material formed a hydrate or solvate during recrystallization and whether the form would remain stable through drying and storage. Prior batches showed inconsistent XRPD patterns between runs.
Challenges: The material converted between an anhydrate and a hydrate depending on water activity, and a solvate formed when the intermediate was recrystallized from certain alcohols. The team could not reliably distinguish these forms or predict conversion during processing.
Solution: We characterized the isolated forms by XRPD, TGA and Karl Fischer titration, then mapped the anhydrate–hydrate boundary using DVS and water-activity experiments across multiple temperatures. TGA-FTIR and TGA-MS confirmed the nature of included solvent in the solvate. Accelerated storage trials established which form was robust under normal handling, and a recommended drying and storage envelope was defined. Twelve independent characterization runs were performed to confirm reproducibility.
Outcome: The client obtained a clear form map with the stable anhydrate identified, along with practical drying and storage guidance that eliminated the run-to-run XRPD inconsistency.
Client Needs: A medicinal chemistry group managing multiple ionizable lead candidates needed a combined salt and co-crystal screen to improve the solubility and crystallinity of three structurally related compounds. The free forms were amorphous or weakly crystalline and unsuitable for downstream study.
Challenges: The three analogues behaved differently, and some counter-ions formed sticky or unstable solids. The team needed a defensible basis to select a salt or co-crystal route for each candidate without over-committing material.
Solution: We screened a panel of counter-ions and co-crystal formers for each analogue, then ran polymorph screening on the most promising salts. Solids were evaluated by XRPD, DSC/TGA and moisture sorption, with intrinsic solubility measured for the shortlisted forms. For each candidate we generated between 20 and 40 unique solid samples and produced an integrated comparison, allowing the team to select a developable salt or co-crystal with supporting stability and solubility data.
Outcome: Each candidate was paired with a recommended solid-form route backed by orthogonal data, and the client advanced the shortlisted salts into formulation feasibility with clear development confidence.
Polymorph formation is influenced by solvent composition, supersaturation, temperature, cooling or evaporation rate, agitation, concentration, water activity, impurities, seeding, and isolation or drying conditions. These variables affect nucleation, crystal growth, and the relative stability of competing forms. A form produced under one condition may also convert during filtration, washing, drying, milling, or storage. Therefore, polymorph screening uses a diverse and controlled condition matrix to determine which crystal forms appear and which conditions favor their formation and persistence.
XRPD is commonly used to generate characteristic diffraction fingerprints and distinguish crystalline phases. DSC and TGA provide information about melting, solid-state transitions, dehydration, and desolvation, while Raman spectroscopy, FTIR, and solid-state NMR can reveal differences in molecular environments and interactions. Candidate forms may also be compared using DVS, solubility, dissolution, slurry-equilibrium, and stability studies. Reliable form assignment generally requires agreement between complementary analytical methods because a single technique may not fully distinguish mixtures, partially desolvated materials, or closely related structures.
Polymorph screening is commonly performed after a compound with a confirmed structure and suitable chemical quality becomes available, but before the final crystallization process and formulation strategy are selected. An early screen can reveal major solid-form risks and provide candidates for initial development. More focused screening may follow as the synthetic route, process solvents, or dosage-form requirements become clearer. Reassessment can also be useful when material sources, crystallization conditions, drying procedures, particle-processing steps, or storage environments change, since these factors may produce or favor a different solid form.
Sample requirements depend on the screening scale, compound solubility, number of experimental conditions, analytical methods, and the need for form reproduction or property comparison. Limited-material projects can use microscale solubility assessment, miniaturized crystallization, and staged screening to obtain useful information from smaller quantities. Broader programs generally require additional material for XRPD, thermal analysis, moisture studies, solubility testing, slurry experiments, and stability evaluation. BOC Sciences designs the experimental scope around the available quantity and confirms a practical sample-allocation plan before laboratory work begins.
A BOC Sciences polymorph screening project can include starting-material review, baseline characterization, solvent and condition matrix design, crystallization experiments, solid isolation, XRPD comparison, and orthogonal characterization of selected forms. Depending on the project objective, additional studies may evaluate thermal behavior, hygroscopicity, solubility, dissolution, slurry conversion, phase interconversion, and stability. The final report organizes the identified forms, preparation conditions, analytical evidence, phase relationships, relevant performance differences, and potential development risks, providing a structured basis for solid-form selection and subsequent experimental planning.
BOC Sciences designed a screening matrix that covered far more conditions than we had budgeted for ourselves. The team explained the solvent and temperature choices clearly, and the resulting form map was easy to act on.
— Dr. Larson, Senior Formulation Scientist
The characterization report combined XRPD, DSC, TGA and solubility data in a way our team could review quickly. We could see which form was most stable and which had the best dissolution, all in one document.
— Tremblay, Project Manager, Solid-State Development
From the initial discussion to the final report, the project moved smoothly. BOC Sciences handled crystallization, characterization and stability work with strong coordination and kept us informed at each stage.
— Dr. O'Hartmann, Lead Scientist, Crystallization
What stood out was the clear recommendation at the end. BOC Sciences did not just list the forms; they ranked them by stability and practicality and suggested the route we should develop, with the risk notes we needed.
— Kramer, Research Director, API Development
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