Color, Packaging Drive Pharmaceutical Inspection Systems

Perhaps no other industry operates under as strict quality regulation and product tracking guidelines as the pharmaceutical industry. The European Union and US Food and Drug Administration's (FDA) 38-page CFR21 Part 11, among others, requires extensive documentation of pharmaceutical production lines to ensure that electronic files related to drug products are 100 percent accountable, auditable and not mislabeled or changed at a later date. Part 11 'applies to all computer systems that create, modify, maintain, archive or retrieve electronic [files],' according to the rule.

'You have to be able to lock the information and make sure it isn't manipulated,' explained Bob Leiby, sales and quality manager for SVResearch Inc. (Harrisburg, PA). 'Security and databases are a big part of it, but each customer has to tell us how they interpret CFR21. In some ways, it's a loose and undefined [rule].'

The level of inspection required by governmental bodies has prompted pharmaceutical manufacturers to pursue automated vision inspection systems from experienced companies with gusto. And while automated inspection and record keeping remain top priorities, new drug packaging trends and product tracking requirements are pushing the boundaries of automated inspection systems as they seek to keep up with a changing industry.

From surface inspection to blister packs

AC Compacting LLC (North Brunswick, NJ) made a business out of selling inspection systems to the pharmaceutical industry for surface inspection. 'It started out with a tablet vision inspection system for surface defect issues that were culturally driven by the Japanese marketplace. In America, we don't tend to look at the tablet before we put it in our mouth. That's not true in Japan. Now, people are looking at this technology for additional purposes beyond looking at tablets prior to packaging…[such as] looking at tablets in a blister pack both pre- and post foiling,' said Bob Fortier, a partner at AC Compacting LLC.

According to Fortier, inspecting tablets in a blister pack is growing more complicated as branding efforts prompt pharmaceutical companies to package their tablets in colors that closely resemble the tablet itself. 'We have to determine very slight differences in color at production speeds and defects as small as 70 microns,' Fortier added. 'You also have to be able to handle a wider variety of tablets, because so much of the pharmaceutical packaging industry has been outsourced to contract manufacturers that work with many product lines.'

A key to conquering the color/defect issue in pharmaceuticals is lighting, Fortier said. Other companies are also experiencing success in developing new lighting techniques, including Key Technology Inc. (Walla Walla, WA). Key's application engineer Keith Bendix said he recently developed a proprietary lighting module for blister packs that moves away from fiber delivered light to a low-cost module that combines the light source and diffusing filters. 'This light will allow us to handle multiple blister pack configurations, including circular and others,' Bendix said.

Light issues can be dealt with both at the source and the receiver. Sabrie Soloman, president of American SensoRx (Glen Rock, NJ) and published author on industrial sensors, has developed new algorithms based on relationship coefficient functions of fast Fourier transformation, cosine transformation, and genetic algorithms, embedded with neural network analyses to help reduce the role of lighting in pharmaceutical and other industrial applications. Soloman said that in difficult inspection applications, such as identifying and counting the number of bristles in each tuft of a toothbrush, data acquisitions using standard OTS equipment and transforms were too slow for end users. 'These methods are generic and could not be adaptive or flexible,' Soloman said. He suggests that American SensoRx, Inc., has developed innovative means to capture, identify and analyze objects at a very high speed (160 objects per second) using simple or barely visible lighting environment.

Host based still rules market for many applications

Not all vision suppliers need to use dedicated hardware solutions or neural analysis to create their pharmaceutical solution. According to Dave DeJean, regional sales manager for SYSTECH International (Cranbury, NJ), product handling speeds in the traditional pharmaceutical industry - for tablet, capsule and vial  packaging - is the  limiting factor, not the automated inspection system.

'We haven't had to go to more dedicated processing. Most people are predominately host based,' DeJean said. 'Think about it from a practical standpoint. A blister machine works at 60 cycles per minute … at 200 tablets per machine stroke area. The processing isn't what's slowing it down, but the ability to stably feed the product. So what we're seeing in trends are things like high resolution and higher spectral analysis for color analysis.'

Creative branding methods by pharmaceutical companies are prompting ever more complex packaging methods, including those where the color of the blister pack closely matches the tablet. Add to that European regulations that require the single dose packages and a growing body of pharmaceutical products - each different in size, shape or color -- and vision suppliers continue to face tighter system requirements. 'We had one customer that put a mauve birth control tablet in a mauve blister pack - wonderful,' DeJean said.

World pharmaceutical markets are increasingly following the European lead in shifting to single dosage packs, such as blister packs. Creative branding and anti counterfeiting measures that depend on very specific tablet colors and printing are pushing vision applications in this area to have greater spectral discrimination.

Bright stocking & nude labeling

AC Compacting's Fortier claims that 'invisible' color, also known as bright stocking (as in stocking of shelves) or nude labeling, is now emerging as a new labeling trend. 'It's driven by the anti-counterfeiting issue. We've recently introduced an ultra high quality tablet printing technology … that uses special inks and inspection techniques to [create] barcodes on the tablet itself,' Fortier said.

Bright stocking and nude labeling techniques such as these, where labeling is not immediately obvious to a consumer, are typically used when there is manufacturing disconnect between the production of the drug and the packaging, according to SYSTECH's DeJean. 'Customers have been asking us for years to uniquely identify those products in an unobtrusive way. We've provided a solution that puts an ultraviolet matrix code on the bottom or top of the container, a code that's not visible to the customer.

Nude labeling is a similar application, but with a different business case. The sterilizing facility at baby formula plants is one example of a production line that needs a large minimum size order to operate cost effectively. However, smaller markets and countries may not be able to meet the minimum order requirement. In that case, DeJean said, the manufacturer produces extra product on large runs and stores it. Using UV codes, the product is traceable, but does not have the additional cost of stripping a temporary label.

OCR and OCV applications used to track product in the pharmaceutical manufacturing process remain the largest vision application in the industry, but new business approaches are creating new variations on the theme.

UV printing and labeling individual tablets are still new in the pharmaceutical industry compared to the more traditional OCR and OCV applications used to check lot codes and track product, but even these mature applications are changing to meet new customer needs. 'If there's a poorly printed or smudged label, customers want to reject that product off the line without operator involvement. But if they encounter an incorrectly printed character they need to stop the line immediately. Then they have to do a line clearance, which is  basically like getting an act of Congress to get the line started again. So to minimize any disruption in production, when a character or label falls below the threshold, we search it against the entire model library. If you search for it and don't find a viable candidate, then it's a no read, not a no match, so you can get rid of that one unit and not worry about cross contamination. It's a simple methodology, but tweaking the algorithms to search through the entire model sets quickly was the key,' DeJean said.
 

COMPANY INFORMATION

American SensoRx, Inc.
139 Harristown Road
Glen Rock, New Jersey 07452, USA
Tel: (201) 447-8999
Fax: (201) 447-8998

AC Compacting LLC
1577 Livingston Avenue - P.O. Box 7266
North Brunswick, NJ 08902-7266 USA
Tel: (800) 524-0183 or (732) 249-6900
Fax: (732) 249-6909

SVResearch Seidenader
SVResearch enc.
7429 Allentown Boulevard
Harrisburg, PA 17112 USA
Tel: (717) 540-0370
Fax:(717) 540-0380

SYSTECH International
7 Clarke Drive
Cranbury, NJ 08512 USA
Tel: (609) 395-8400
Fax: (609-395-0064

Key Technology, Inc.
150 Avery Street
Walla Walla, WA 99362 USA
Tel: (509) 529-2161
Fax: (509)527-1331