HI4004

Description

The HI4004 is a liquid membrane, half-cell ion selective electrode (ISE) for the determination of calcium (Ca2+) in solution. The PVC membrane comprised with organic ion exchanger produces a potential change due to the calcium ion exchange between the organic polymer membrane and the sample. The internal sensing elements are housed within a durable epoxy body. The HI4004 is ideal for a variety of applications in the food and beverage industry and water analysis.

• Detection from 0.12 to 40,080 mg/L Ca2+
• For use with HI5315 reference half-cell
• Liquid membrane sensor

The HI4004 calcium ion selective electrode is a potentiometric half-cell sensor housed within an epoxy body. The internal elements are isolated from the sample by an organic polymer sensing PVC membrane. This liquid membrane sensor requires a separate reference electrode to complete the measurement system.

Hanna’s liquid membrane half-cell ISEs are designed for use with the HI5315 reference half-cell. The reference half-cell features a cone style junction. The skirted cone geometry of the sensor forms the liquid junction with the test solution at the tip of the junction cone, producing a highly stable reference potential and consistent flow rates of electrolyte into the solution. A simple press of the top portion of the ISE makes it easy to empty the electrolyte fill solution and replace when necessary.

For the HI4004 to measure calcium accurately, it is important that the ionic strength of the standards and sample be adjusted to a high and constant value with the calcium ionic strength adjuster (ISA) solution. The ISA ensures that the activity coefficient is constant so the concentration of free calcium ions can be measured. Measuring all solutions with a constant ionic strength reduces the margin of error between measurements. The HI4004 calcium liquid membrane ISE can measure from 3µM (0.12 mg/L) to 1M (40,080 mg/L).

Conversion Table for Ca²⁺

	Multiply
moles/L (M) to ppm (mg/L) :	40080
ppm (mg/L) to M (moles/L) :	2.49 x 10^-5

Features at-a-glance
BNC Connection
• The HI4004 has a universal BNC connector for easy connection to any benchtop meter with a female BNC probe input.

Durable Epoxy Body
• The probe body of the cyanide half-cell ISE is composed of durable epoxy resin.

Replaceable Sensing Modules
• Half-cell liquid membrane ISEs are electrodes that detect free ions in a solution.
• The HI4004 calcium half-cell ISE is designed to incorporate easy replacement of the sensing module.

SPECIFICATIONS

Type :	polymer membrane; half-cell
Measurement Range :	Calcium (Ca²⁺) 1.0M to 3•10^-6M, 40,080 to 0.12 mg/L (ppm)
Optimum pH Range :	pH 4 to 10
Temperature Range :	0 to 40 °C
Approximate Slope :	+28 mV
Diameter :	12 mm
Overall Length :	120 mm
Body Material :	epoxy, PVC
Cable :	coaxial; 1 m (3.3’)
Connection :	BNC
Warranty :	6 months