Loader
In spite of test in vitro and in vivo, we also took our first step to make ECHO a real product.
ECHO Capsules
After we visited Roche with Tongji_China, we have been thinking about the proper load of ECHO. In our interview with Lingjie Zhou, who is responsible for quality assurance in Roche, she talked about the advantage of capsules compared with other pharmaceutical preparations, which are listed below.
- High bioavailability
- Reliable stability
- Flexible form
- Good compliance of patients
- Easy manufacture
More about our interview with Roche.
After the visit, we decided to collaborate with Tongji_China, to purchase the enteric capsule, DRcaps, from Capsugel, a global pharmaceutical dosage solutions company. This kind of capsule can protect product ingredients form stomach acid so that it can release ECHO in colon where our device is supposed to function.
Fig 1. ECHO capsules.
Hydrogel beads
Alginates are linear natural polysaccharide which could respond to the calcium and produce a three-dimensional (3D) network of chain cross linking, serving as promising materials for drug delivery. This time we introduced sodium alginates to make hydrogel covered bacteria beads, which was suspended in drinking water, facilitating oral administration of our engineered bacteria.
The strenghs of hydrogel beads are
- Easy to produce food grade beads
- Stable for E.coli delivery
- Adjustable to produce different sizes
- Safe to degradation in vivo
The overall process of hydrogel beads production was shown in Fig.2.
Fig 2. Illustration of bacteria loaded hydrogel.
Fig 3. Hydrogel beads loaded with engineered bacteria.