BOC Sciences provides solid form screening and selection services that help drug discovery and development teams characterize the crystalline and amorphous landscape of their compounds, compare polymorphs, salts, cocrystals, and amorphous forms, and select a lead solid form that balances solubility, stability, and manufacturability. Our work connects early in vitro solubility behavior with crystallization science, structural characterization, and downstream process thinking, so that form decisions are supported by data rather than assumption.
A solid form is the physical state in which a compound exists as a solid, defined by its molecular packing, crystallinity, hydration, and ionization state. The same molecule can adopt multiple solid forms, including polymorphs, salts, cocrystals, solvates, hydrates, and amorphous solids, each with distinct physicochemical behavior. Solid form screening is the systematic search, preparation, and characterization of these forms to build a complete landscape, while form selection chooses the lead form that best supports the intended product profile. Form selection matters because it directly influences dissolution, exposure, chemical and physical stability, hygroscopicity, powder flow, and filterability, and it also shapes intellectual property options. Choosing the wrong form late in development can force costly rework, whereas identifying a stable, performant form early reduces downstream risk. BOC Sciences supports teams across discovery, lead optimization, and early development stages with tiered screening that scales with material availability and project urgency.
We map the crystalline form landscape of free forms, salts, or cocrystals by varying the conditions that govern nucleation, growth, and solid-state conversion.
For ionizable compounds, BOC Sciences evaluates counterions and crystallization conditions to identify salt candidates with useful solid-state and biopharmaceutical properties.
Cocrystal screening provides an alternative route for neutral, weakly ionizable, or salt-forming compounds whose available forms do not meet target property needs.
We assess whether an amorphous form can provide a useful performance advantage and whether that advantage can be maintained against recrystallization.
Share your molecular structure, available material, ionization profile, known forms, solubility limitations, target dosage form, and current processing challenge. BOC Sciences will design a focused plan covering form generation, characterization, comparative testing, and selection.
Solid form assignment and selection require complementary methods. BOC Sciences combines structural, thermal, moisture, microscopic, spectroscopic, and performance measurements so that a candidate is not advanced on the basis of one signal alone.
| Technology | Primary Use in Solid Form Studies |
| X-ray Powder Diffraction (XRPD) | Provides a characteristic diffraction fingerprint for phase identification, form comparison, mixture review, crystallinity assessment, and monitoring of transformations under selected conditions. |
| Differential Scanning Calorimetry (DSC) | Measures melting, glass transition, crystallization, desolvation, and solid-solid transitions, supporting interpretation of polymorphic relationships and amorphous behavior. |
| Thermogravimetric Analysis (TGA) | Tracks temperature-dependent mass loss to investigate water or solvent content, desolvation and dehydration events, and thermal decomposition. |
| Dynamic Vapor Sorption (DVS) | Measures moisture sorption and desorption across controlled relative humidity to support hygroscopicity testing, hydrate-risk assessment, and amorphous-form evaluation. |
| Polarized Light Microscopy (PLM) | Visualizes crystal habit, particle morphology, agglomeration, and birefringence; hot-stage microscopy can help relate visible changes to thermal events. |
| Solid-State Nuclear Magnetic Resonance (ssNMR) | Provides local molecular-environment information that complements diffraction and spectroscopy for polymorph differentiation, amorphous-content review, and salt or cocrystal confirmation. |
| Solubility and Dissolution Measurements | Compare equilibrium behavior, dissolution rate, supersaturation, precipitation, and solution-mediated conversion to determine whether a form offers a useful performance advantage. |
BOC Sciences can begin with a material-sparing risk screen or design a broader landscape study. Experimental depth, analytical escalation, and candidate testing are adjusted as evidence develops, helping direct material toward the forms and questions that matter most.
We design crystallization arrays spanning solvent, anti-solvent, temperature, pH, and seeding conditions, then generate forms using cooling, evaporation, slurry, and precipitation routes. Recrystallization and solvent-exchange triage help maximize form diversity from limited material.
Each solid is profiled by XRPD, DSC, Raman, and microscopy to classify forms, detect amorphous content, and group identical materials, building a reliable form inventory for downstream comparison.
Candidate forms are compared for solubility, dissolution, stability, hygroscopicity, and processing behavior, then ranked against the target product profile to narrow the field to a few defensible options.
We nominate a lead form with clear rationale and verify reproducibility through a baseline crystallization route, with scale-up checks to confirm the form can be made consistently at larger quantities.
A limited solvent screen may repeatedly recover the supplied material while missing metastable polymorphs, hydrates, solvates, or process-induced forms. BOC Sciences expands the relevant experimental space using solvent-diversity design, multiple crystallization routes, water-activity variation, temperature cycling, slurry conversion, seeding, and mechanical stress. XRPD clustering and orthogonal analysis distinguish genuine forms from duplicates, mixtures, desolvated products, and crystallinity differences, producing a clearer landscape and a risk-ranked plan for further work.
The thermodynamically stable polymorph may offer excellent physical stability but insufficient solubility or slow dissolution. We compare free forms, salts, cocrystals, metastable crystalline forms, and amorphous options while monitoring whether apparent solubility gains are lost through precipitation or solution-mediated conversion. When solid form modification alone cannot meet the target, results can guide solubility improvement and formulation strategies that preserve an acceptable balance between performance and stability.
Hydrates, solvates, amorphous materials, and some salts can transform when exposed to water activity, drying conditions, solvent residues, or formulation environments. We combine DVS, controlled-humidity exposure, TGA, DSC, XRPD, Karl Fischer water testing, and residual solvent analysis to identify transition boundaries and conversion pathways. These data support selection of a more robust form and define practical controls for isolation, drying, milling, handling, and storage studies.
The most stable form is not automatically the most useful. A stable crystal may dissolve slowly, a soluble salt may be hygroscopic, and a rapidly dissolving amorphous form may recrystallize. BOC Sciences uses multi-attribute ranking to compare stability, solubility, dissolution, moisture response, morphology, electrostatic behavior, flow, compactability, and preparation feasibility. This makes the selection rationale transparent and allows teams to choose a lead form that matches the real formulation and process priorities.
Collaborate with BOC Sciences to map solid-form diversity, characterize phase relationships, compare development attributes, identify transformation risks, and establish a reproducible path toward the form best suited to your compound and application.
BOC Sciences evaluates each form against the attributes that matter for the intended program, including physical stability, solubility, dissolution, hygroscopicity, particle behavior, preparation reproducibility, and formulation compatibility. Weighted comparison prevents a single attractive measurement from masking a critical weakness and supports a selection decision that reflects the compound's complete developability profile.
Diverse crystallization conditions, stress studies, phase-relation experiments, and process-relevant testing are used to expose hydrate formation, salt disproportionation, amorphous recrystallization, metastable conversion, and mechanically induced changes before a process is built around the wrong form. Early evidence can reduce repeated formulation work, unexpected batch behavior, and costly changes after material requirements have increased.
Expanded polymorph, salt, and cocrystal studies can uncover forms with distinct structures and property profiles. BOC Sciences generates reproducible preparation procedures and orthogonal data packages covering identity, composition, thermal behavior, stability, and comparative performance. These scientific records can support evaluation by the client's patent specialists, while novelty, patentability, claim scope, and freedom to operate remain legal determinations.
Our support can connect starting-material assessment, form generation, rapid triage, advanced characterization, property comparison, crystallization development, scale-up verification, and downstream formulation services. Maintaining one technical thread across these stages helps preserve the rationale behind form selection and enables new data to be interpreted against the original screening landscape.
Client Needs: A discovery team had a weakly basic heteroaromatic kinase inhibitor with variable XRPD patterns across synthesis batches. The team needed a physically stable crystalline form with reproducible preparation and acceptable dissolution for oral formulation research.
Challenges: The supplied solid contained two closely related patterns, formed a hydrate in water-rich media, and partially converted during drying. The apparent stable form also showed slower dissolution than the mixed starting material.
Solution: We designed 48 crystallization experiments covering cooling, evaporation, antisolvent addition, slurry conversion, and temperature cycling across 14 solvent systems. XRPD clustering separated four reproducible patterns. DSC, TGA, DVS, variable-temperature XRPD, and competitive slurry studies established relative stability and hydrate-conversion pathways. The selected anhydrous form was then reproduced at larger laboratory scale and monitored during filtration, drying, and milling.
Outcome: The study identified a thermodynamically stable anhydrous polymorph, defined conditions that avoided hydrate formation, and established a reproducible preparation route with consistent physical stability.
Client Needs: An oral formulation group needed a salt form of a poorly soluble basic compound that combined improved aqueous behavior with manageable powder flow and low wall adhesion during blending.
Challenges: Early salt hits were crystalline but differed markedly in hygroscopicity, needle formation, electrostatic charging, and filterability. The most soluble hit adhered strongly to stainless-steel surfaces and formed cohesive agglomerates.
Solution: We screened 12 counterions and generated salt candidates by cooling, antisolvent, and slurry methods. XRPD and ion analysis confirmed salt identity, while DSC, TGA, DVS, microscopy, particle sizing, shear-cell flow testing, and charge-to-mass measurements compared powder behavior. Two lead salts were recrystallized under adjusted supersaturation and cooling profiles, and the lower-charging form was verified in a small-scale excipient blending study.
Outcome: A crystalline salt with lower charging tendency, improved handling, and suitable solubility was selected, reducing wall adhesion and simplifying subsequent oral formulation experiments.
Solid form screening may evaluate polymorphs, anhydrates, hydrates, solvates, salts, cocrystals, and amorphous materials. The appropriate scope depends on the molecular structure, ionizable groups, solubility profile, crystallization tendency, and development objectives of the compound. For example, salt screening is generally relevant to ionizable APIs, while cocrystal or amorphous form screening may be considered for poorly soluble neutral compounds. Experimental conditions can vary in solvent, temperature, concentration, cooling rate, and crystallization method. Analytical techniques such as XRPD, DSC, and TGA are then used to distinguish forms and map the accessible solid-state landscape.
The most suitable solid form is not necessarily the form with the highest solubility or the greatest thermodynamic stability. Selection requires a balanced comparison of physical and chemical stability, solubility, dissolution rate, hygroscopicity, transformation risk, particle characteristics, flowability, compressibility, and crystallization reproducibility. The intended formulation and anticipated manufacturing conditions should also be considered. Orthogonal analytical techniques are used to confirm form identity, while stress studies help reveal potential changes during processing or storage. This multi-attribute approach supports a more informed selection and reduces the risk of relying on a single favorable property.
Solid forms can respond to changes in solvent composition, water activity, temperature, humidity, supersaturation, seeding, drying, milling, and compression. An amorphous material may recrystallize during storage, a solvate may lose solvent during drying, and a salt may undergo disproportionation under certain moisture or medium conditions. Polymorphic conversions may also occur when processing conditions favor a more stable crystal structure. For this reason, solid form evaluation should extend beyond identifying the initial sample. It should also examine phase relationships and transformation pathways under relevant processing and storage conditions to identify physical stability and manufacturing risks early.
BOC Sciences provides polymorph, salt, cocrystal, and amorphous form screening tailored to the characteristics of each compound and the needs of each project. Our support can include experimental matrix design, sample generation, high-throughput crystallization studies, XRPD pattern classification, thermal analysis, hygroscopicity testing, solubility and dissolution assessment, powder property evaluation, and candidate ranking. For promising forms, we can also support crystallization condition optimization, repeat preparation, transformation risk studies, and laboratory-scale process verification. The resulting data package helps clients compare candidates systematically and establish a clear, traceable basis for solid form selection.
Useful starting information includes the chemical structure, molecular weight, ionizable groups, available pKa data, known solid forms, synthesis and isolation history, solvents previously used, and existing analytical results. Details about observed solubility, stability, crystallization, filtration, drying, or powder-handling issues can further improve study design. Clients may also share the intended formulation, anticipated processing conditions, available material, and the primary objectives of form selection. BOC Sciences can use this information to identify likely solid-state risks and propose either a focused screening program or a broader solid form investigation aligned with the project needs.
BOC Sciences compared several salt and amorphous options for our poorly soluble compound and gave us clear dissolution and stability data. We could see which form offered the best bioavailability potential without guessing.
— Dr. Rodriguez, Principal Scientist, Solid-State Chemistry
Our amorphous dispersion kept recrystallizing during storage. The team profiled glass transition and storage behavior and recommended a stabilization route that reduced recrystallization risk in our batches.
— Dr. Anderson, Senior Formulation Scientist
Finding the right polymorph early saved us from a major reformulation later. The screening output gave our project team confidence and avoided expensive late-stage rework and lost timeline.
— Dr. Ramirez, Project Leader, Drug Product Development
The solid-state data package was complete and easy to trace. Every form was supported by XRPD, DSC, and Raman, which made internal review and downstream decisions straightforward.
— Dr. Ruiz, Analytical Lead, Pharmaceutical Sciences
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