Stationary Felodipine Basket | Dissolution Accessories

APPARATUS 1 - USP The rotating basket apparatus consists of a cylindrical basket held by a shaft. The basket holds the sample and rotates in a round flask containing the dissolution medium. All Baskets are equivalent to the original OEM. Is there something you can't find, please feel free to contact us for custom work.

PSBSK040-01-USP-apparatus-I-1-basket-Agilent-40-mesh

Agilent Compatible baskets

Caleva baskets

PSBSK040-DK-USP-apparatus-I-1-basket-Distek-40-mesh

Distek baskets

Electrolab baskets

PSBSK020-EW-USP-apparatus-I-1-basket-Erweka-20-mesh

Erweka baskets

PSBSK100-HR-USP-apparatus-I-1-basket-Hanson-100-mesh

Hanson / Teledyne baskets

Logan baskets

PSBSK010-PTG-USP-apparatus-I-1-basket-gold-coated-Pharmatest-10-mesh

Pharmatest baskets

PSBSK040-ST-USP-apparatus-I-1-basket-Sotax-40-mesh

Sotax baskets

Zymark baskets

Stationary Baskets

PSSTABSKF-01-USP-26-Felodipine-Stationary-basket-for-Agilent

Stationary Felodipine Basket

PSBSKSUP-01-USP-apparatus-I-1-suppository-basket-plastic-Agilent

Suppository baskets

Basket accessories Dissolution accessories provides solutions for costumers all over the world. Whether it is about storing baskets, checking them against USP standards or attaching them to a basketshaft.

All Basket accessories

BASKET SHAFTS The rotating basket assembly is individually serialized with the serial number laser imprinted on the shaft for record keeping purposes. These assemblies meet USP specifications requiring three retention spring clips for Apparatus 1 or o-ring push-on style. Shafts are standard electropolished, but also avaialble with different types of coatings.

Agilent Compatible basket shaft

PSBSKSHT16-02-USP-apparatus-I-1-basket-shaft-Distek

Distek basket shaft

PSBSKSHT16-EL-USP-apparatus-I-1-basket-shaft-Electrolab

Electrolab basket shaft

PSBSKSHT16-EW-USP-apparatus-I-1-basket-shaft-Erweka

Erweka basket shaft

Hanson / Teledyne basket shaft

PSBSKSHT16-PT-USP-apparatus-I-1-basket-shaft-Pharmatest

Pharmatest basket shaft

PSBSKSHT-AT7-USP-apparatus-I-1-basket-shaft-Sotax

Sotax basket shaft

PSBSKSHT-ZM2-USP-apparatus-I-1-basket-shaft-conical-Zymark-Caliper

Zymark basket shaft

PSBSKSHT-DEM-USP-apparatus-I-1-basket-shaft-Dabigatran-Etexilate-Mesylate

Dabigatran Etexilate Mesylate (DEM)

Basket height spacers

PSPADHLD-12A-Dissolution-Accessories-12-Position-Paddle-And-Basket-Shaft-Holder

Basket shaft holders

PSMINBSK-40-Small-Volume-Mini-Basket-40-Mesh-Hanson

Agilent

PSMINBSK-40-Small-Volume-Mini-Basket-40-Mesh-Universal

Distek

Erweka

Hanson / Teledyne

APPARATUS 3 - USP Biodissolution, also known as USP apparatus 3, is ideal for dissolution profiling of extended release dosage forms or any dosage form requiring release profiling at multiple pH levels. All parts are equivalents of the original OEM.

PSEVACOV-05-USP-Apparatus-III-3-PVC-Evaporation-Cover-Agilent

Caps & covers

PSGLA300-02-Dissolution-Accessories-Clear-Glass-300-mL-USP-Apparatus-3-Vessel

Vessels & sampling tubes

Screens

CALIBRATION TOOLS Qualification tools for performance verification testing and mechanical qualification for example (ASTM E2503-13). All of our tools are calibrated and USP/NIST traceable and can be used on multiple brands of dissolution testers.

PSASTMKT-Dissolution-accessories-ASTM-calibration-toolkit

ASTM / USP Qualification Tool Kit

PSDEPGAG-DA-Dissolution-Accessories-ASTM-Digital-depth-gauge

Depth set tools

ASTM Qualification Tools

PSPRED-TAB-USP-Prednisone-Calibration-Tablets

USP Prednisone Standards & Tablets

pH meter

Dissolved oxygen meter

Conductivity meter

(Re)Calibration service

CANNULA FILTERS Filters are used on the end of a sampling cannula and feature a large surface area and optimized flow rate for an ideal choice in applications with a high presence of particulates. Filters are traceable by lot number and meet all current guidelines of USP and FDA.

PSFIL001-01-1000-Dissolution-Accessories-Cannula-Filter-UHMW-Polyethylene-1-Micron-Agilent

Agilent Compatible cannula filters

PSFIL001-HR-100-Dissolution-Accessories-Cannula-Filter-UHMW-Polyethylene-1-Micron-Hanson

Caleva cannula filters

PSFIL010-DK-1000-Dissolution-Accessories-Cannula-Filter-UHMW-Polyethylene-10-Micron-Distek

Distek cannula filters

PSFIL001-FF-100-Dissolution-Accessories-Cannula-Filter-Full-Flow-UHMW-Polyethylene-1-Micron

Electrolab cannula filters

PSFIL001-HR-1000-Dissolution-Accessories-Cannula-Filter-UHMW-Polyethylene-1-Micron-Hanson

Erweka cannula filters

PSFIL001-FF-1000-Dissolution-Accessories-Cannula-Filter-Full-Flow-UHMW-Polyethylene-1-Micron

Full Flow cannula filters

Hanson cannula filters

PSFIL001-LI-1000-Dissolution-Accessories-Cannula-Filter-UHMW-Polyethylene-1-Micron-LabIndia

LabIndia cannula filters

Logan cannula filters

Pharmatest cannula filters

Sotax cannula filters

DISSOLUTION SINKERS
Floating dosage forms rarely dissolve at a reproducible rate. Using a sinker together with Apparatus 2 fixes the dosage form to a certain point and aids reproducibility. Sinkers can also be useful where dosage forms may stick to the sides of the vessel. Our sinkers can also be used in disintegration testing to prevent floating dosage forms.

Capsule size	Length		Diameter
Capsule size	(inches)	(mm)	(inches)	(mm)
000	1.029	26.1	0.390	9.91
00E	1.012	25.7	0.336	8.53
00	0.917	23.3	0.336	8.53
0E	0.909	23.1	0.301	7.65
0	0.854	21.7	0.301	7.65
1	0.765	19.4	0.272	6.91
2	0.709	18.0	0.250	6.35
3	0.626	15.9	0.229	5.83
4	0.563	14.3	0.209	5.32
5	0.437	11.1	0.193	4.91

Alf-(uzosin)/ Rop-(inirole) Hydrochloride cylinder sinker

PSBSK008-01-Dissolution-Accessories-basket-sinker

Cage & basket sinkers

Metformin hydrochloride vertical holders

Stainless steel wire

Pouch

Time release capsule sinker

DISINTEGRATION TESTING The current apparatus described in the Pharmacopoeias was designed to provide a reproducible and standardized method of ensuring that disintegration has taken place. Each of the tablets to be tested is placed in one of 6 vertical tubes arranged in a circular basket arrangement. The lower end of the tubes is covered by a sieve mesh. Other tubes sizes for larger tablets are also available.

Agilent Compatible disintegration accessories

Caleva disintegration accessories

Charles Ischi disintegration accessories

Copley disintegration accessories

Distek disintegration accessories

Electrolab disintegration accessories

Erweka disintegration accessories

Hanson disintegration accessories

Pharmatest disintegration accessories

Pharmatron/Secom disintegration accessories

Sotax disintegration accessories

ProSense disintegration accessories

DISSOGUARD SYSTEMS With a unique design and powerful software the dissoGUARD® is a dissolution surveillance system that will revolutionize the way you see the dissolution procedure. With cameras placed underneath a dissolution bath the user is not only able to see and store real time videos, export pictures or complete videos for future analyses. For the first time, the user is able to measure or predict different physical parameters of their dissolution apparatus. With different algorithms the software can evaluate the wobble and measure RPM, determine the proper center alignment of individual shafts, and much more. Through the various stages of dissolution procedure it is possible to evaluate the proper position of dosage forms, timing and position of sampling cannulas, behavior of particles in vessels, etc.

DissoGuard

Conversion kits

Accessories

MEDIA CONCENTRATES Dissolution Media Concentrates are consistant and cost effective to use. Dilute the concentrate by simply adding purified water, you will create “ready to use” dissolution media within a few minutes.

Media Preparator

Acetate buffer pH 4.5

Citrate buffer pH 4.8

Hydrochloric acid 0.01N

Hydrochloric acid 0.1N

Potassium Phosphate pH 4.5

Potassium Phosphate pH 5.8

Potassium Phosphate pH 6.0

Potassium Phosphate pH 6.5

Potassium Phosphate pH 6.8

Potassium Phosphate pH 7.2

Potassium Phosphate pH 7.4

Potassium Phosphate pH 7.5

Simulated Gastric Fluid (without enzyme)

Simulated Intestinal Fluid (without enzyme)

Sodium Lauryl Sulfate 0.50%

Sodium Phosphate pH 6.8

PSFTLL-013-6005-Female Luer Fitting Female Luer Thread Style to 500 Series Barb, 18 (3.2 mm) ID Tubing, Animal-Free Natural Polypropylene

Barb Fittings

PSLE87-6-Dissolution-Accessories-Female-Luer-to-Male-Luer-Elbow-Style

Luer fittings

Handbook of dissolution testing

Fittings

APPARATUS 4 - USP The principal of this apparatus consists of a reservoir containing the dissolution medium, a pump that forces the medium upwards through the vertically positioned flow-cell, and a device to control the temperature in the cell.

PSAPP4FC-12S-Sotax-compatible-USP-apparatus-IV-4-flow-cell-12mm-acrylic

USP 4 Flow through cells

PSCELLHLD-APP4-Aluminum-cell-holder-for-USP-IV-4-apparatus

USP 4 Cell holder

INTRINSIC DISSOLUTION - USP The intrinsic dissolution rate is defined as the rate of dissolution of a pure pharmaceutical active ingredient when conditions such as surface area, agitation-stirring speed, pH and ionic-strength of the dissolution medium are kept constant. The determination of this parameter allows for screening of drug candidates and an understanding of there solution behaviour under different bio-physical conditions. All parts are equivalents of original OEM.

Intrinsic dissolution apparatus set

PSIDASNH-01-Shaft-and-Holder-Intrinsic-Dissolution-Agilent

Intrinsic Shaft & holder

PSIDAPLT-01-Surface-Plate-with-Screws-Intrinsic-Dissolution

Intrinsic Surface plate with screws

PSIDADIE-01-8-mm-Die-including-gasket-Intrinsic-Dissolution

Intrinsic die

PSIDAPCH-01-8-mm-Punch-and-Handle-Intrinsic-Dissolution

Intrinsic Punch and handle

PSIDAPRS-01-Dissolution-Accessories-2-ton-Press-Universal

Intrinsic press

APPARATUS 2 - USP The dosage form is dropped into the medium, which is stirred with a paddle attached to the stirring shaft. All paddles are equivalent to the original OEM.

PSEPD013-01-USP-Apparatus-II-2-Electropolished-Paddle-14-5-inch-Agilent

Agilent Compatible paddles

PSEPDCA-01-USP-Apparatus-II-2-Electropolished-Paddle-Caleva

Caleva paddles

PSEPD016-02-USP-Apparatus-II-2-Electropolished-Paddle-16-inch-Distek

Distek paddles

PSEPD016-EL-USP-Apparatus-II-2-Electropolished-Paddle-16-inch-Electrolab

Electrolab paddles

PSEPD016-EW-USP-Apparatus-II-2-Electropolished-Paddle-16-inch-Erweka

Erweka paddles

Hanson paddles

PSEPD016-DK-USP-Apparatus-II-2-Electropolished-Paddle-16-5-inch-Distek

Logan paddles

PSEPD016-PH-USP-Apparatus-II-2-Electropolished-Paddle-16-inch-Pharmatest

Pharmatest paddles

PSEPDPAD-AT7-USP-Apparatus-II-2-Electropolished-Paddle-for-AT7-Sotax

Sotax paddles

Paddle height spacers

Paddle holders

Agilent

PSMINEPD-HR-Small-Volume-Electropolished-Mini-Paddle-Spin-On-Off-Style-Hanson

Hanson / Teledyne

Pipettes
Pipettes for easy, safe and precise sampling. We have pipettes in various volumes, suitable for any application. All pipettes are tested according to ISO 8655/DIN 12650

Single channel pipettes

Pipette accessories

CANNULAE Sampling cannulae are used to take samples from the dissolution test and can be bend for easier accessibility to USP sampling position.

Agilent Compatible sampling cannula

Caleva sampling cannula

Distek sampling cannula

Electrolab sampling cannula

Erweka sampling cannula

Hanson sampling cannula

High capacity sampling cannula

Pharmatest sampling cannula

Sotax sampling cannula

Disposable sampling cannula

SERVICE PARTS To keep dissolution instruments in optimum condition, a variety of equivalent parts are offered to service the OEM systems.

Agilent Compatible

Zymark Multidose G3

SPIN SHAFT - USP Interchangeable Paddle/Basket Shaft, also know as Spin On/Off shafts, allows the user to switch between paddles and basket shafts without height readjustment. The system is a two-piece assembly engineered to easily set the shaft length to maintain consistent clearance from the bottom of the vessel.

Agilent Compatible spin on/off shafts

Distek spin on/off shafts

Erweka spin on/off shafts

Hanson spin on/off shafts

Pharmatest spin on/off shafts

Glass syringes

Plastic Disposable syringes

Stainless Steel Syringes

Automation filters

PSDSC-CA25-045-0150-Dissolution-Accessories-Cellulose-Acetate-Syringe-Filter

Cellulose Acetate (CA)

PSDSC-CA25-080-0150-Dissolution-Accessories-Cellulose-Acetate-Syringe-Filter

Cellulose Nitrate (CN)

PSDSC-GF25-100-0150-Dissolution-Accessories-Glass-Fibre-Syringe-Filter

Glass Fiber (GF)

PSDSC-HP25-020-0150-Dissolution-Accessories-PTFE-Hydrophilic-Syringe-Filter

PTFE Hydrophilic (HP)

PSDSC-NY25-020-0150-Dissolution-Accessories-Nylon-Syringe-Filter

Nylon (NY)

PSDSC-PB25-045-0150-Dissolution-Accessories-PTFE-Hydrophobic-Syringe-Filter

PTFE Hydrophobic (PB)

PSDSC-PP25-045-0150-Dissolution-Accessories-Polypropylene-Hydrophobic-Syringe-Filter

Polypropylene Hydrophobic (PP)

PSDSC-PS25-020-0150-Dissolution-Accessories-Polyethersulfone-Syringe-Filter

Polyethersulfone (PS)

Polyester (PT)

PSDSC-PV25-010-0150-Dissolution-Accessories-PVDF-Syringe-Filter

PVDF (PV)

PSDSC-RC25-022-0150-Dissolution-Accessories-Regenerated-Cellulose-Syringe-Filter

Regenerated Cellulose (RC)

TAPPED DENSITY - USP Tapped density is achieved by mechanically tapping a volumetric cylinder containing a powder. The tapping is achieved by raising the cylinder and letting it drop under its own weight from a specific height. The mass increase is measured.

The Tapped Density Testers have been designed to measure the tapped density of powders, granules and similar products in accordance with USP Chapter <616> Method 2 and European Pharmacopoeia Chapter 2.9.15.

PSGLA100TP-01-Graduated-Funnel-Top-Cylinder-Agilent

Agilent Compatible tapped density funnels

PSGLA250FT-DK-250-mL-Graduated-Funnel-Top-Cylinder-Distek

Distek tapped density

PSGLA250ST-EL-250-mL-Graduated-Funnel-Top-Cylinder-Electrolab

Electrolab tapped density

PSGLA250FT-EW-250-mL-Graduated-Funnel-Top-Cylinder-Erweka

Erweka tapped density

PSGLA250ST-ST-250-mL-Graduated-Funnel-Top-Cylinder-Sotax

Sotax tapped density

Tubing is recommended for use with the Peristaltic Pump, syring pumps or any other fluidic path. Regular replacement of this tubing is recommended to prevent contamination. It is important to maintain the proper tubing lengths between components. Please visit our service part section for more specialised tubing between hardware components.

Aurosampler / Peristaltic pump tubing

PTFE tubing

Tygon tubing

The “Paddle over Disk” is a modified version of Method 2 (Paddle Method) and is used for the determination of the drug release rate of transdermal patches. It is described in the United States Pharmacopoeia (USP) under Chapter <724> as Method 5 and in the European Pharmacopoeia (Ph.Eur.) under Chapter 2.9.4. Method 1 as ‘Disk Assembly Method’.

Patch holders

Patch holder accessories

APPARATUS 6 - USP An alternative method for the testing of transdermal patches, USP Method 6 (Ph.Eur. Chapter 2.9.4. Method 3) employs the same dissolution equipment as Method 1 simply substituting a cylinder stirring element in place of the standard basket. The rotation speed normally employed is 100 rpm. The element is designed to accept various sizes of patches.

Agilent Compatible rotating cylinders

Copley rotating cylinders

Distek rotating cylinders

Electrolab rotating cylinders

Erweka rotating cylinders

Hanson rotating cylinders

Logan rotating cylinders

Pharmatest rotating cylinders

PSAPPSIX-ST-USP-apparatus-VI-6-Rotating-Cylinder-short-for-sotax

Sotax rotating cylinders

VERTICAL DIFFUSION CELL.

Creams, ointments, lotions and gels are topical drugs normally described as semisolid dosage forms. Unlike transdermal drug systems (see Note) which are applied to the skin for systemic effects (the drug penetrates the skin whereupon it is then absorbed into the blood stream), topical drugs are applied to the skin for local action principally to counter dermatological problems. Current USP thinking suggests two types of test to characterise semisolids, product quality tests (USP Chapter <3>) and product performance tests (the proposed USP Chapter <1724>).

The Vertical Diffusion Cell or Franz Cell is a simple, reproducible test for measuring the drug release from creams, ointments and gels. It is rapidly emerging as the apparatus of choice for the in vitro testing of drug release of topical semisolid dosage forms. The cell comprises two parts (a) the sample holder containing either 250 mg or 425 mg of the sample to be tested and (b) the reservoir of the diffusion cell itself containing the receptor medium. The two parts are separated by a membrane designed to act as a conduit for diffusion to take place and which serves to contain the test sample whilst ensuring that it remains in contact with the receptor medium. The receptor temperature is usually set to 32 degrees C to approximate normal skin conditions. Normally, no fewer than 6 samples are taken over a 6 hour period, say, 0.5, 1, 2, 4, 5 and 6 hours and analysed using HPLC or similar analytical technique.

Manual Franz cell systems

Franz cell

Kerski cells

APPARATUS 5 - USP - USP - EP 2.9.4. A variation to apparatus 2 with various methods as described in the USP and/or EP. The dosage form is applied to the apparatus and then placed at the bottom of the vessel.

PTFE suspension cups

Vessels - USP <711> Dissolution Accessories vessels are USP <711> and ASTM compliant. Vessel are serialized and will be supplied with a certificate of compliance. All DA manufactured vessels are compatible with the dimensional specifications of the OEM. This is important so the hydrodynamical propertities remain equivalent. All vessels are available in PEAK, Amber or Teflon coated. Please contact us for an inquiry

PSGLA900-01-Dissolution-Accessories-1-Liter-Clear-Glass-EaseAlign-Vessel-Agilent

"Glass Rim" vessels

PSGLA900-TA-Dissolution-Accessories-1-Liter-Clear-Glass-TruAlign-Vessel-Agilent

"Plastic Rim" vessels

PSGLA900-VKC-1-Liter-Clear-Dissolution-Vessel-with-Collar-Agilent

"Magnetic Collar" vessels

PSGLA900-CA-Dissolution-Accessories-1-Liter-Clear-Glass-Vessel-Caleva

Caleva vessels

PSGLA900-ZM-Dissolution-Accessories-1-Liter-Clear-Glass-Vessel-Zymark

Caliper/Zymark vessels

PSGLA900-CP-Dissolution-Accessories-1-Liter-Clear-Glass-Vessel-Copley

Copley vessels

PSGLA900-DK-Dissolution-Accessories-1-Liter-Clear-Glass-Vessel-Distek

Distek vessels

PSGLA900-EL-Dissolution-Accessories-1-Liter-Clear-Glass-Vessel-Electrolab

Electrolab vessels

PSGLA900-EW-Dissolution-Accessories-1-Liter-Clear-Glass-Vessel-Erweka

Erweka vessels

PSGLA900-HRV-Dissolution-Accessories-1-Liter-Clear-Glass-Vessel-Collar-Vision-Hanson

Hanson / Teledyne vessels

PSGLA900-LG-Dissolution-Accessories-1-Liter-Clear-Glass-Vessel-Logan

Logan vessels

PSGLA900-PT-Dissolution-Accessories-1-Liter-Clear-Glass-Vessel-Pharmatest

Pharmatest vessels

PSGLA900-ST-Dissolution-Accessories-1-Liter-Clear-Glass-Vessel-Sotax

Sotax vessels

PSGLA900-TO-Dissolution-Accessories-1-Liter-Clear-Glass-Vessel-Toyama

Toyama vessels

VESSEL ACCESSORIES Vessel accessories designed to keep your vessels in excellent condition.

Vessel stands

PSPRORNG-ST-Protective-Reing-For-AT7-Vessel-Sotax

Vessel protection rings

Centering brackets / Rings These centering rings position the vessels accurately using diameter of the vessel. Empty vessels will not float. Locating pegs mounted on the vessel table ensure centering each time a vessel is placed in position. Our rings and brackets fit the original OEM.

PSEZLBKT-01-Vessel-Centering-Bracket-Model-7000-7010-705-DS-Agilent

Agilent Compatible vessel brackets/rings

PSRING01-DK-Acculign-Centering-Ring-Distek

Distek vessel brackets/rings

PSCNTRNG-EW-Vessel-Centering-Ring-Erweka

Erweka vessel brackets/rings

PSCNTRNG-HR-Vessel-Centering-Ring-Hanson

Hanson vessel brackets/rings

Logan vessel brackets/rings

PSRETRNG-ZM-Multidose-Vessel-Retainer-Zymark

Zymark vessel brackets/rings

COVERS Evaporation covers slow the loss of media during dissolution testing. There are many types available, conical designs to return condensation into the vessel, low loss evaporation covers which dramatically reduces media loss during long runs, the two-piece hinged evaporation cover and covers with sample openings for cannulae.

PSCOVERV-00-Low-evaporation-rotary-cover-Agilent

Agilent Compatible vessel covers

Distek vessel covers

Hanson / Teledyne vessel covers

Pharmatest vessel covers

High Precision Vessels - USP Highest specification vessels, with precise sphericity, circularity, concentricity of inner surface, vertical center and uniform geometry. Reduces variations in dissolution results and creates better conditions to pass the USP PVT (Performance Verification Test) at Stage 1.

PSHPGLA900-01-Dissolution-Accessories-1-Liter-High-Precision-Clear-Glass-EaseAlign-Agilent

Agilent Compatible high precision vessels

PSHPGLA900-CP-Dissolution-Accessories-1-Liter-High-Precision-Clear-Glass-vessel-Copley

Copley high precision vessels

PSHPGLA900-HR-Dissolution-Accessories-1-Liter-High-Precision-Clear-Glass-SR8-Hanson

Distek high precision vessels

Electrolab high precision vessels

Erweka high precision vessels

Hanson / Teledyne high precision vessels

Logan high precision vessels

Pharmatest high precision vessels

Sotax high precision vessels

Toyama high precision vessels

Zymark high precision vessels

PSHPGLA900-ACP-Liter-High-Precision-Amber-Dissolution-Accessories-Copley

Caleva high precision vessels

SMALL VOLUME A variation on apparatus 1 & 2 are available based on scaled down versions of the standard apparatus.

PSSMVASSY-HRV-Dissolution-Accessories-Small-Volume-Vessel-Adapter-Ring-Vision-Hanson

Small volume adapters

PSKIT200-DK-1-Dissolution-Accessories-200-mL-Clear-Glass-vessel-Small-Volume-Kit-Round-Bottom-Distek

Small volume conversion kits

Hanson / Teledyne

Sotax

VOLUMETRIC GLASSWARE Available as Tc / Td and according to ASTM- or USP standards.

Volumetric Flasks Tc/Td

Clear volumetric flasks ASTM/USP certified

Amber volumetric flasks ASTM/USP certified

PSFLEAK-300-Dissolution-Accessories-Glass-Fleaker-300-mL

Fleakers

ALGEACIDE An algeacide stops the growth of algae, bacteria and other microorganisms with its bactericidal effectiveness. It protects the bath fluid and ensures a clean bath fluid.