CALLI-L Librarian

Powder Distribution and Weighing System for Library Compounds

Calli Librarian

Compound libraries are the potential gold mines of pharmaceutical and chemical companies. Liquid handling for the dissolution of the library compounds has been automated for many years. The most tedious procedure, though, the distribution and weighing of the original solid dry-stored library compound, is still done manually. The CALLI-L fills this gap. It is specifically designed for the distribution of dry, powder library samples for dissolution, distributing the samples directly from their original library vial without any additional preparation step.

CALLI-L is based on the well-proven Zinsser liquid handling platform with integrated powder and liquid handling, a weighing cell, mixing devices, a capper/ decapper and a visual camera. The customer library vials are placed in racks on the platform.

CALLI-L is an automatic workbench system, 1.5 or 2m long, customized to the individual requirements for medium or high throughput. It is based on a X,Y,Z pipetting station with an integrated robotic arm which can be equipped with all the functions needed for dissolution of the compounds:

The combination of clever hardware and software make CALLI-L the ideal workhorse for sample preparation of library samples. By automating the entire workflow and using the original sample containers, it frees laboratory staff from the tedious, time-consuming and repetitive work so that they can concentrate on more intelligent tasks.

Sample Identification
For sample identification the library compounds are placed in barcode labeled vials on the platform. CALLI-L reads from the barcode which compound it is handling, how many dissolution vials shall be prepared, which target concentration should be reached. Each sample is tracked throughout the run.

Sample transfer
The distribution process is controlled by a built-in weighing cell to monitor the mass distribution of powders in the range from less than 1mg to 50mg. CALLI-L detects the level of the solid material in the library vial. Even a small layer on the bottom can be transferred to the dissolution vial or plate.

Addition of solvent
Based on the actual weight and the given target concentration the solvent is added. Up to 6 different solvents can be handled in one run, using the integrated 6-way valve.

Visual Monitoring
An integrated camera checks the dissolution status of the compound and based on its result it can trigger different actions: Mixing by vortexing, sonication, addition of a different solvent or in the end it can discard the sample from the rest of the run. The camera can check the dissolution status of the samples at any given time.

For efficient mixing vortexers, magnetic stirrers or overhead stirring are available which are integrated into the platform. All mixing devices can be equipped with software-controlled temperature control.

The samples can be sonicated by either using a sonication probe or by placing the sample containers into a sonication bath. The sonication step can either be implemented as a standard routine in the method for all samples or it can be used as an extra treatment where necessary.

Argon Shield
For hygroscopic compounds and when handling DMSO to minimize the risk of compound precipitation the entire dissolution step can be performed under argon. With its enhanced technology it is not necessary to flood the entire system with argon thus keeping the cost and weight of the instrument to a minimum.

User-Friendly Software
The WinCALLI software controls the weighing, dissolution and sample distribution. It keeps track of the samples and exchanges data with all commercial mass storage databases such as ORACLE®. With the scheduler, it controls and optimizes the methods, enabling the system to work with both arms completely independently. A complete sample audit trail is provided, which is used to control the system and for the documentation of each run.

Capping & Decapping
A capper/decapper unit can open and close screw capped sample vials to minimize their exposure to air. It can also close the reactors to prevent evaporation.

High Reproducibility & Precision
Weight reproducibility depends upon the particle size distribution within the sample. Powders with narrow particle size show precise distribution with excellent reproducibilities. Test results with different powders have given reproducibilities of ±5% for 1mg,±3% for 10mg, ±1% for 50mg, and 1% for 150mg.