Hydroxypropyl B Cyclodextrin ,Endotoxin controlled

Hydroxypropyl B Cyclodextrin ,Endotoxin controlled

                        replaces Encapsin(tm) brand which is no longer available

                            Catalog#: RDI-410200   $1,100.00/kilogram   $1000.00/kg 5-14  $900.00/kg 15+

Data Sheet: Hydroxypropyl B Cyclodextrin, Endotoxin Controlled     cat#RDI-82004HPB  $1,100.00/kilogram

                     -a high purity material with a higher degree of substitution  $1000.00/kg 5-14  $900.00/kg 15+

see also pharmaceutical grade below (high purity but NOT Endotoxin Controlled-

not recommended for an invivo or cell culture applications)

cat#RDI-82005HPB   $750.00/1kg  $700.00/kg 2-9   $650.00/kg 10-49

Package Size: 1 kilogram

Description: Hydroxypropyl B-Cyclodextrin Endotoxin controlled -suitable for parenteral use. It is a water soluble, free flowing, white odourless powder. It is produced from Beta-cyclodextrin by hydroxpropylation of the hydroxyl groups of the cyclodextrin.

Functionality: suitable for molecular encapsulation of a variety of sparingly water soluble compounds to enhance the aqueous solubility of the encapsulated compounds. It is manufactured for and tested to meet proposed USP-N specifications. In addition to increase the solubility, the stability of the guest compound can be enhanced and the volatility can be reduced. This product is chemically stable and does not contribute significantly to viscosity until very high concentrations (>50%) are reached.

                                                             (=spec range unique to that product)

Sample Batch spec cat#RDI-410200 cat#RDI-82004HPB cat#RDI-82005HPB
Degree Substitution 4.3(4.1-5.1) 6.5 (6.0-8.0) 5.2 (4.0-6.0)
ASH (0.5% max) 0.1% 0.2% 0.1%
Propylene Glycol (0.5% Max) 0.03% 0.2% 0.3% (1.5%)
Moisture (5% Max) 1.9% 4% 3.7% (8.0%)
specific rotation +141 DEG (+138-+144) +131 DEG (+120- +140) +138 (+120 - +150)
pH(1% solution) 5.0-8.0 7.2 6.0 6.9
unmodified BCD 0.2% (1% Max) 0.1 (0.1% Max) 0.1% (1%max)
Aerobic Plate Count CFU/g --- -- 20CFU/g

(1000CFU/g max)

Appearance in solution (10%) Clear Clear --
Endotoxins EU/g

max 0.01EU/mg

<0.01EU/mg <0.01EU/mg not determined
Total Viable Aerobic Bacteria

max 10CFU/g

<1CFU/g <1CFU/g not determined
Total Viable Fungi

max 1CFU/g

Heavy Metals 20ppm Max <20ppm <20ppm  
Price     $1,100.00/kilogram $1,100.00/kilogram $750.00

cas# 128446-35-5

Application: solubilization of poorly soluble compounds in water*

Stabilization of labile and reactive compounds*


*NOTE: Specific applications may be covered by prior patent law

-in USA suggest contacting National Institute of Health licensing office


Storage: Store in a cool dry place, off the ground and away from chemicals and odorous materials. Good ventilation   should be provided. DEG C.

TSCA: THis product is listed on the TSCA Inventory

-no hazards identified to date


other legislation: AICS, ELINCS listed   DMF 13081


CN Code 3505 10 10


Safety Dust is flammable and explosive


Precautions: For  research Use Only.


It is the responsibility of the user to comply with all local/state and Federal rules in the use of this product. We are not responsible for any patent infringements that might result with the use of or derivation of this product.

Note:Degree of substitution is the average number of hydroxypropyl groups per cyclodextrin. Some individual moleculaes in the mixture will have less than the average and some will have more substitutions than the average. The degree of substitution can be determined by FTIR (Fourier Transform InfraRed Spectroscopy) or NMR (Nuclear Magnetic Resonance Spectroscopy). Molecular weight is calculated after determining the degree of substitution. Molecular weigth is equal to the molecular weight of BCD plus the product of the molecular weight of the hydroxypropyl group times the degree of substitution.

          MW= 1135 + (58)(DS)


specific rotation can be used as a measure of purity. The specific rotation is dependent upon the degree of substituion and decreases as the degree of substitution increases. The expected contaminants in HPBCD result from the synthesis. these are salt and propylene glycol.

Background information:Hydroxypropyl B-Cyclodextrin (HPBCD)

Hydroxypropyl Beta Cyclodextrin (HPCD) (cas#94035-02-6) is a partially substituted poly(hydroxpropyl) ether of beta cyclodextrin (BCD). The empirical formula is: (C42 H70-n O35) . (C3 H7 O)n It contains not less than 10.0 percent and not more than 45.0 percent hydroxypropoxy(-OCH2CHOHCH3) groups. the structure is shown below where R represents either hydrogen or a hydroxypropoxy group.

R= CH2CH(OH)CH3 or H

The basic closed circular structure of BCD is maintained in HPBCD. The glycosidic oxygen forming the bond between the adjacent glucose monomers and the hydrogen atoms lining the cavity of the cyclodextrin impart an electron density and hydrophpbic character to the cavity. Organic compounds interact with the walls of the cavity to form inclusion complexes. The hydroxyl groups and the hydroxypropyl groups are on the exterior of the molecule and interact with water to provide the increased aqueous solubility of the hPCD and the complexes made with the HPCD.

Degree of Substitution

The hydroxypropyl groups are randomly substituted onto the hydroxyl groups of the cyclodextrin and the amount of sub- stitution is reported as average Degree of Substitution or number of hydroxypropyl groups per cyclodextrin and is the perferred manner of describing the substitution. An alternate measurement is Molar Substitution or the average  number of substitutions per anhydro gluycose unit in the ring of the cylcodextrin. Molar substitution is used with polymers whose molecular weight is not determined or contains a mixture of polymers of different degrees of polymerization. The cyclodextrin is a defined molecule. Molecular weight is calculated based upon the degree of substitution. Substitution is a distribution aroung the average degree of substitution of the number of hydroxypropyl groups per cyclodextrin with some molecules having more than the  average and some less than the average degree of substitution. The result is a mixture of many molecular species with respect to the number and location of substitutions around the ring of the cyclodextrin. The reaction to produce HPBCD is highly controllable and repeatable so that the product produces is very consistent from batch to batch.

Substitution can have an effect on the binding of guests to the HPBCD. At low degrees of substitution, binding is very similar to that of the unmodified B-cyclodextrin. Increasing substitution can lead to weakened binding due to steric hindreance. The effect is dependent upon the particular guest and it is also possible to obtain increased binding due to an increase in surface area to  which the guest can bind. With most guests, these differences in binding with degree of substitution are small if detectable.

Physical and Chemical Properties


1. Water

HPBCD is very soluble in water. Substitution of the hydroxyl groups of the BCD disrupts the network of hydrogen bonding around the rim of the BCD. As a result of disruption of the hydrogen-bonding network, the hydroxyl groups interact much more strongly with water resulting in increased solubility compared to BCD. Solubilities of HPBCD are typically listed at >60% at amnbient temperature. As the concentraion becomes higher, viscosity begins to increase and solubility determinations become difficult to perform due to slow filtration  rates and at very high solids levels, slow dissolution because of high viscosities making mixing difficult.



HPBCD is more soluble in solvents than BCD, but extensive work has not been done to characterize the solubility of HPBCD in solvents. The table below shows the solubility in selected alcohols.

Solvent Solubility(g/100ml)

DS 7.6 

Solubility (g/100ml)


Octanol n.d. 0.179
Ethanol (95%) 225 200
Iso-Propanol 152 n.d.


The table below shows the solubility of HPBCD in ethanol-water mixtures.'

Ethanol Concentration (%) DS 7.6
  g/100 ml
0 360
20 340
40 320
60 295
80 265
95 225



Unlike BCD whose solubility is limited, solutions of HPBCD can become viscous. At concentrations normally used in applications the viscosity is not a concern. The table below shows the  viscosity of HPBCD at different concentrations and temperatures.

                Viscosity in mPa.s

Temperature 'C 19 30 40 50 60
40% 17.5 14.0 10.5 11.0 8.0
45% 32.5 25.0 19.5 22.0 13.5
50% 56.5 35.0 27.0 23.0 19.0
55% 138.0 72.0 54.5 38.0 32.0
60% 552.0 258.5 153.5 110.0 69.5
65% 1710.0 865.0 485.0 310.0 245.0

Viscosity increases as the concentration increases and decreases as the temperature increases. The increase of viscosity with concentration is slow until a concentration of 55%, where the rate of increase of the viscosity becomes more rapid.

Thermal Stability

A thermogram obtained by differential scanning calorimetry is shown below. Energy is absorbed as water evaporates, peaking at about 100'C. A glass transition occurs in this thermogram from about 225 to 25-'C. The glass transition temperature  varies with the degree of substitution. Thermal decomposition  occurs at 308'C as determined by visual observation using a  capillary-melting apparatus.


Acid/Base Stability

Strong acids, such as hydrochloric or sulfuric acids, hydrolyze HPBCD. The rate of hydrolysis is dependent upon the temperature and concentration of the acid. The higher the temperature or concentration of the acid, the more rapid is the rate of hydrolysis. Weak acids, such as organic acids do not hydrolyze HPBCD

HPBCD is stable in bases. HPBCD is synthesized under basic conditions without opening of the BCD ring.

Within the commonly used range of pH for most products and processes, HPBCD is stable as shown in the table below


  Stability of HPBCD from pH 4.0 to 9.0

  Concentration HPBCD (ug/ml)    
  Initial Day 5 % Hydrolysis
4.0 6.03 5.97 1.0
7.0 5.50 5.70 -3.6
9.0 5.20 5.10 1.9

HPBCD was incubated in buffers at 50'C for five days. The results indicated that little, if any hydrolysis occured.Variation in the assay could account for the differences found.

Enzymatic Stability

HPBCD is not hydrolyzed by B-amylase or glucoamylase. These enzymes require an end group in order to initiate attack. Since HPBCD has no end groups, no hydrolysis occurs with these enzymes.

BCD can be hydrolyzed by some alpha amylases,with fungal alpha amylases being more active than bacterial alpha amylases. The ability of these enzymes and cyclodextrintransglycosylases to hydrolyze HPBCD is limited. Substitution provides steric hindrance to the binding of the HPBCD to the active site of the enzyme and as a result, the amount of hydrolysis is reduces. The greater the degree of substitution, the less hydrolysis that occurs. Hydrolysis is probably largely limited to any unmodified BCD present.