News & Views
Shelf life stability

We aim to ensure your packaging is right first time, enabling you to offer products in optimum condition.

Mark Valentine, R&D Director

Dr Mark Valentine’s expertise gives you confidence your chosen packaging will be fit for purpose, is right and justifiable. He conducts extensive trials to present the most effective packaging solution to minimise moisture-damage; he saves you time and money by avoiding lengthy prototyping cycles and shelf life trials.

He’s trialled every possible packaging scenario; taking into account type of packaging, material, seal, specific drug reactivity, shelf life, storage conditions and temperature.

His knowledge and expertise usually means only one stability trial is necessary (or may negate any trial).

Consultancy service

Dr Valentine offers a bespoke computer model to solve your packaging problem. Using revolutionary SuperDrySim™ modelling software he gives you the chance to get your packaging needs right first time, without undertaking expensive trials.

Dr Valentine computes a picture of what’s happening inside your packaging at any given time. Humidity’s mapped out at every point, using governing fluid mechanics, packaging specifics and desiccant characteristics. Taking into account environmental and climatic conditions, he suggests the correct packaging and where to place/amount of desiccant to maintain product stability.

This free service reduces your stability trials, saves on laboratory resources and staff time plus reduces your packaging costs and helps get your moisture-sensitive products to market sooner.

Choosing the wrong type/amount of desiccant can add months to a product’s development and delay its launch. Better desiccant selection and placement reduces bulk volume/weight of packaging for cheaper transport costs.

Dr Valentine’s carried out extensive research and experimental tests to understand desiccant adsorption behaviour in differing storage conditions and packaging. Environment is defined by temperature and relative humidity (RH) of the air, which gives absolute humidity. Packaging includes different thickness of aluminium foil and vials used for pharma applications. SuperDrySim™ can be applied to any desiccant-based packaging for contents like vitamins, diagnostic kits, medical devices and healthcare products.

How SuperDrySim™ works out your optimum packaging

  • Recognises importance of moisture-control in packaging & computes specific amount of desiccant
  • Protects contents by allowing for atmospheric conditions and using desiccants for moisture adsorption
  • Many products are designed to interact with water eg. effervescent tablets so it’s vital they remain dry
  • Loss of shelf life and product failure can happen very quickly
  • Humidity is mapped over time and space, then verified against experimental data
  • Daily/seasonal temperature and humidity variations are taken into account
  • Frequency of pack opening can be projected
  • Reduces number of stability trials required, saves on laboratory facilities and staff time
  • Shortens time taken to assess shelf life and gets product to market sooner
  • Fewer product returns due to inadequate packaging


SuperDrySim™ 3D modelling software in operation

SuperDrySim™ accounts for changes to both rate of moisture ingress (which will decrease as internal humidity increases) and rate of moisture adsorption of the desiccant. Balance between moisture ingress and moisture adsorption is key.

Desiccants play a vital role in protecting moisture-sensitive products; removing water vapour from the air and preventing undesirable reactions between product and water molecules (hydrolysis).

Effervescent tablet trial


Figure 1 shows degradation of effervescent tablet at 20°C and 80% RH.

Failure occurs despite absence of any liquid water




Modelling humidity in a desiccant vial

Newly developed desiccant vials are two-shot injection moulded, with inside layer consisting customised desiccant formulation and outside layer made of polypropylene. Desiccant vials hold more, and time and money are saved, by not having to insert a separate sachet. Flip-top cap design makes it easy for glove wearers to open and close. In older style packaging, desiccant is positioned in the vial’s lid so moisture gets removed from the top first. SuperDrySim™ 3D model allows for effects of regularly opening/closing these desiccant vials to ensure quality of contents is maintained throughout whole depth of vial.

Humidity gradient trial


Figure 2 shows graphic effect of frequent opening, and closing, on humidity inside two types of tube packaging.

Older style (with desiccant in lid only) on left and new vial (with inside layer of customised desiccant) on right.

Darker blue shows consistent humidity gradient from top to bottom.


Mapping humidity

As desiccant adsorbs moisture, the number of adsorption sites will decrease; the probability of a water molecule being adsorbed at any given time will reduce at a given relative humidity. Relative humidity determines the rate at which desiccant picks up moisture. As the desiccant approaches saturation, the rate of moisture adsorption becomes much slower and a tipping point is reached (where the partially saturated desiccant isn’t able to keep up with moisture entering the pack). At this stage, humidity will start to rise even though the desiccant is still ‘active’.

Modelling active desiccant


Figure 3 shows modelling of average humidity inside a foil pouch for active lifetime of desiccant.

Design lines show 3-year shelf-life and <20% RH.

Graph shows initial moisture pick-up region, followed by a long, slow increase in RH as desiccant adsorption rate falls below moisture ingress rate.


SuperDrySim™ presents the interior of your pack as a cube or cylinder grid, depending on its shape.

Ingress-diffusion-adsorption equations are solved over grid points, giving a three dimensional (3D) view of humidity inside your pack. These grid points are progressed over each time period for the product’s required shelf life; humidity can be ascertained at any time, for any given point inside pack. This valuable knowledge helps reduce man hours and cost of getting a product to market.

Humidity map of foil pouch

Figure 4 shows humidity map, inside  foil pouch with desiccant, during initial moisture pickup stage.

Cooler (blue/green) colours indicate lower RH and hotter (red/orange) colours show higher RH.

Presence of desiccant is clearly seen.


Accelerated stability trials

Stability trials establish whether the desiccant is protecting pack contents as expected. Dr Valentine carries out accelerated stability trials to help speed up your product launch. His established test method rapidly establishes product efficacy. Packaging containing both product and desiccant is tested at fives time the actual storage humidity; one month under test conditions equates to five months in storage. Timescales involved make it important to minimise number of trials undertaken. Even at this accelerated rate, a two year shelf life evaluation will take six months to complete. There’s also a risk of over-desiccation, as water ingress through the packaging can place a greater burden on desiccant adsorption rate, resulting in higher internal humidity than would be present under usual conditions.

In-house R&D expertise

Dr Valentine joined Baltimore Innovations after completing his DPhil at Oxford University, where he worked in the Chemical Engineering Group specialising in fluid mechanics and multiphase flow.

As R&D Director, Dr Valentine works closely with in-house business development team, strategic manufacturers and key supply partners. He develops moisture-control packaging and provides desiccant consultancy and technical support to customers within the defence, energy, food, industrial, medical and polymers sectors.

To discuss how SuperDrySim™ can optimise your packaging, please contact Dr Mark Valentine         01628 531900    


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