Solid State Chemistry

Solid state services to position your programme for success

We deliver the solid state services, tools, and technologies needed to support your development programme that delivers an API with the desired characteristics to enhance material efficiency and therapeutic success.

Solid state chemistry at Sterling

Identifying the optimal solid form of your API is a critical step in its journey to market. Your product’s solid form directly impacts its solubility, bioavailability, and therapeutic efficacy. In addition, selecting the right solid form early on enables more efficient and cost-effective development and manufacturing processes, mitigating the risk of unanticipated challenges. At Sterling, our comprehensive solid state chemical services enable us to help you bring the ideal form of your API through manufacturing and to the market.  ... Read more

Our team’s solid state expertise, paired with the state-of-the-art equipment and analytical laboratory in our Material Science Centre, support extensive solid form investigations and robust crystallisation development programmes. By fully understanding your project requirements and working closely with you, we select the optimal target solid form and ensure its suitability for manufacture and commercialisation.

Not only are our solid state services available as part of an integrated development campaign, we can provide standalone solid form screening and crystallisation development packages tailored for your specific requirements.Read less


Fast Facts

State-of-the-art facilities:

Our Material Science Centre is equipped to support your solid state requirements.

Expert teams:

Our solid state scientists have a range of experience to support our client’s API solid state investigation and development requirements in partnership.

Comprehensive solid form solutions:

Our solid state chemistry team is capable of identifying the ideal version of your API at any stage through four interconnected areas of investigation: salt selection, polymorph investigation, pre-formulation evaluation and crystallisation development, aided by a range appropriate analytical techniques.

Learn more about our solid state capabilities and analytical techniques.

Salt and cocrystal screening enable us to manipulate your API’s solubility, dissolution profile, and physiochemical properties. We utilise screening investigations to identify a salt or cocrystal version that delivers enhanced solubility and bioavailability. These investigations not only offer a means to aid in early development and purity control; they can also be utilised to generate intellectual property for your API.

Through polymorph screening, we determine your API’s potential to take on different solid forms. As with salt and cocrystal screening, polymorph screens can enable us to identify key properties of your API, that can have an impact upon efficacy, stability, and impurity control.

Identifying the propensity of an API to polymorphism early on enables us to recommend the ideal API target via form hierarchy that delivers the appropriate efficacy and stability and can proactively overcome challenges in the long run to avoid added costs and extended timelines. As with salt screening, we can tailor an expanded polymorphism investigation to generate intellectual property for your API forms.

If multiple potential solid forms are identified as possibilities through salt, cocrystal, and polymorph screening, pre-formulation evaluation enables us to assess the API versions suitability under various conditions. Understanding how different solid form variations respond to external factors enables us to identify which candidate is best suited to move forward. We consider parameters such as solubility and stability in aqueous and biorelevant buffers, form and chemical stability through stability investigations and the physical resilience of the solid to mechanical stresses.

Initial evaluations enable us to select the best solid form to move forward to crystallisation development, progressing to production of your API solid. Crystallisation enables us to control purity levels, and afford the target API version with appropriate particle habit and size distribution.

Crystallisation development is among the most important and most challenging aspects of API development, as it must address numerous physical characteristics of the API and ensure the desired solid form version can be achieved repeatedly. Crystallisation impacts numerous key physical properties that are integral to supporting smooth operations moving forward. An API’s material characteristics can have implications for filtration and drying, secondary processing, and drug product manufacture.

We work closely with our clients to understand and resolve their crystallisation challenges. Our crystallisation development services enable us to deliver your optimal solid form in a repeatable and scalable way. When tailoring your crystallisation development programme, we consider cost, time, and HSE without compromising product quality.

A range of analytical techniques support our solid state services, enabling us to identify your API’s preferred characteristics:

  • X-Ray Powder Diffraction (XRPD)
  • Differential Scanning Calorimetry (DSC)
  • ThermoGravimetric Analysis (TGA)
  • Dynamic Vapour Sorption (DVS)
  • Infra-red Spectroscopy (FTIR)
  • Ultraviolet Spectroscopy (UV)
  • 1H NMR Spectroscopy
  • Ion Chromatography (IC)
  • Optical Microscopy
  • Hot Stage Microscopy (HSM)
  • Particle Size Distribution (PSD)
  • High Pressure Liquid Chromatography (HPLC)
  • Gas Chromatography (GC)
  • Dissolution Assessment

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