Liquid Flow Sensor LD20
Single-use Flow Sensor for Biomedical Applications
Safe, precise, and reliable measurement of low flow rates in medical environment has never been so easy: The single-use liquid flow sensors of the LD20 series measure the liquid flow rate directly and at the point of interest for a more effective patient treatment and improved safety.
Nowadays, keywords and trends such as point-of-care, patient compliance, complex drug administering, and wearable designs demand the development of smart medical devices. The LD20 series combines Sensirion’s proven liquid flow sensing technology with a single-use, cost-optimized design for high volume applications in the medical, life-science or food industry. The sensor provides a bidirectional measurement of flow rates from 1000 ml/h down to single-digit ml/h, while it as well reliably detects common failure modes such as occlusion, free flow, or air bubbles with unprecedented speed and sensitivity.
The LD20 series optimizes costs by reducing the flow sensor to its bare minimum while still ensuring easy fluidic, electrical and mechanical connections. Barbed or luer lock fittings guarantee secure and straight-forward integration into the fluidic line: for example, into a catheter or an infusion set. Inert wetted materials provide outstanding chemical resistance and excellent media compatibility.
When using a sensor of the LD20 series, drug delivery can be measured precisely and in real time. Consequentially, drug therapies become more effective, as they become easier to monitor and control. The LD20 liquid flow sensor series enables medical device manufacturers to enhance the safety, performance, and reliability of their products for the benefit of patients and care givers.
The LD20 Series
LD20-2600B: ±1000 ml/h, barbed fittings
LD20-0600L: ± 20 ml/h, luer lock fittings
For quick and easy testing, a ready-to-use kit is available. Together with the provided software, it enables a plug and play connection of the sensor to a PC. The LD20 evaluation kit can be ordered from our distributors.
- Full scale flow rate for water-based liquids: 1000 ml/h
- Bidirectional measurement and real time failure detection
- Highest sensitivity for detection of infiltration and multi-infusion settings
- Media isolation: No contact of the sensor chip with valuable medications or body fluids
- High speed measurement: Response time < 50 ms
- Low power consumption: Suitable for battery-powered applications
- Highly integrated: Fully calibrated, linearized, and temperature compensated digital I2C signal from a single chip
- Highly scalable sensor design: Competitive pricing for single-use applications
- Biomedical devices
- Advanced infusion therapy
- (Wearable) drug delivery devices
- Urine catheters
- Surgical instruments
Yet Another Technical Gap Closed: Measuring Lowest Flow Rates in Medical Therapies
Medical procedures and therapies are often faced by the same challenge: accurately measuring and controlling lowest flow rates down to the microliter per hour range. In most of these cases the outcome of the therapy, as well as the well-being or even the survival of the patient strongly rely on the reliable and continuous drug administration in such low flow regimes. While various countermeasures have been evaluated and introduced, there is still room for improvement and for new technologies to be established. One novel development with tremendous potential is a single-use liquid flow sensor that is able to measure lowest flow rates and detect common failure modes quickly and reliably.
Advanced Failure Detection of the LD20 Series
Due to Sensirion’s unique CMOSens® Technology, the LD20 liquid flow sensor is sensitive enough to detect the smallest changes in the flow rate. For instance, when integrated into an infusion set, it is so sensitive that it can detect the regular peaks in the infusion flow rate produced by the oscillating back pressure of the patient’s venous pulse – the sensor can feel the patient’s heartbeat.
Detecting the heartbeat on the flow rate is a direct indication of an intact connection of the infusion cannula to the vein of the patient, absence of the pulsation on the contrary indicates an interrupted connection. Possible causes may include e.g. kinked, disconnected or, ruptured tubing or a dislodged infusion cannula which may in turn lead to infiltration. By evaluating the sensor signal, Sensirion’s sensor solution offers a unique possibility of detecting infiltration quickly and preventing harmful consequences to the patient.
Closed loop constant flow rate flow source for high precision applications
In a typical lab environment, microfluidic experiments can often rely on external sources like pressurized air to drive media through the experiment. TTP Ventus manufactures the Disc Pump™, a small air pump, that can be used to build independent or even portable pressure driven flow sources for microfluidic applications. The advantage of a pressure driven flow source are the stable and non-pulsatile flow rates created over a large dynamic range. In order to leverage the full potential of such a flow source, the SLF3S-0600F liquid flow sensor for example can be used to create a small and highly integrated closed feedback loop system. By including the real time flow rate reading of the liquid flow sensor, the pump controller can drive the pump in exactly the right way to create the desired flow rates. Both, single and permanent use designs can be achieved by this approach.