For TOC analysis of particle containing samples the multi N/C® series offers the direct injection system and waste water specialist multi N/C® 2100 or the all-rounder multi N/C® 3100. By direct injection of multi N/C® 2100 the sample is drawn up directly into a micro liter syringe and introduced into the combustion system, without tubing and valve. The wide-bore needle and the septum-free injection head ensure the optimum particle handling capability and leak-free continuous operation. The all-rounder multi N/C® 3100 brings highest sample throughput. This flow injection system guarantees robust, representative sample transfer by large inner tubing diameters. The back-rinse technique prevents blockages. Teflon wear in the dosing syringe is prevented. Inside the dosing valve the approved and robust ceramic technique is used. Thus, the highest operation standard in terms of particle handling, productivity and low wear is realized.