SIXTH AMENDED AND RESTATED
                          CERTIFICATE OF INCORPORATION
                             OF THERMOGENESIS CORP.
 
 
     ThermoGenesis Corp., a corporation organized and existing under the laws of
the State of Delaware, (the "Corporation") hereby certifies as follows:
 
         1. The original Certificate of Incorporation of the Corporation was
filed with the Secretary of State of the State of Delaware on July 3, 1986,
under the corporate name Refrigeration Systems International.
 
         2. A Certificate of Merger was filed with the Secretary of State of the
State of Delaware on September 26, 1986, whereupon the Corporation's name
changed to Insta Cool Inc. of North America.
 
         3. A Restated Certificate of Incorporation of the Corporation was filed
with the Secretary of State of the State of Delaware on March 24, 1994.
 
         4. An Amended and Restated Certificate of Incorporation of the
Corporation was filed with the Secretary of State of the State of Delaware on
January 12, 1995, changing the Corporation's name to THERMOGENESIS CORP.
 
         5. An Amended and Restated Certificate of Incorporation of the
Corporation was filed with the Secretary of State of the State of Delaware on
June 5, 1996.
 
         6. An Amended and Restated Certificate of Incorporation of the
Corporation was filed with the Secretary of State of the State of Delaware on
August 2, 1999.
 
         7. A Fifth Amended and Restated Certificate of Incorporation of the
Corporation was filed with the Secretary of State of the State of Delaware on
October 28, 2005.
 
         8. This Sixth Amended and Restated Certificate of Incorporation was
duly adopted by the Board of Directors and stockholders of the Corporation in
accordance with Sections 242 and 245 of the Delaware General Corporation Law and
restates and integrates and further amends the provisions of the previous filed
Amended and Restated Certificate of Incorporation of this Corporation.
 
         9. The current Amended and Restated Certificate of Incorporation is
hereby amended and restated in its entirety to read as follows:
 
         FIRST:  The name of the corporation is:  THERMOGENESIS CORP.
 
         SECOND: The address, including street, number, city and county, of the
registered office of the Corporation in the State of Delaware is 2711
Centerville Road, Suite 400, Wilmington, County of Newcastle, Delaware 19808;
and the name of the registered agent of the Corporation in the State of Delaware
at such address is The Company Corporation.
 
         THIRD: The nature of the business or purposes to be conducted or
promoted of this Corporation shall be to engage in any lawful act or activity
for which corporations may be organized under the General Corporation Law of
Delaware.
 
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         FOURTH: The Corporation is authorized to issue two classes of stock,
designated Common Stock, $0.001 par value ("Common Stock") and Preferred Stock,
$0.001 par value. The total number of shares of Common Stock that the
Corporation shall have authority to issue is Eighty Million (80,000,000) and the
total number of Shares of Preferred Stock that the Corporation shall have
authority to issue is Two Million (2,000,000).
 
         The Corporation has no issued or outstanding shares of its previously
authorized Series A Convertible Preferred Stock. Accordingly, all rights,
preferences, privileges and restrictions granted to or imposed upon such series
of shares have been omitted from this Sixth Amended and Restated Certificate of
Incorporation.
 
         Shares of Preferred Stock may be issued from time to time in one or
more series. The Board of Directors shall determine the designation of each
series and the authorized number of shares of each series. The Board of
Directors is authorized to determine and alter the rights, preferences,
privileges and restrictions granted to or imposed upon any wholly unissued
series of shares of Preferred Stock and to increase or decrease (but not below
the number of shares of such series then outstanding) the number of shares of
any such series subsequent to the issue of shares of that series. If the number
of shares of any series of Preferred Stock shall be so decreased, the shares
constituting such decrease shall resume the status which they had prior to the
adoption of the resolution originally fixing the number of shares of such
series.
 
         FIFTH: Whenever a compromise or arrangement is proposed between this
Corporation and its creditors or any class of them and/or between this
Corporation and its stockholders or any class of them, any court or equitable
jurisdiction within the State of Delaware may, on the application in a summary
way of this Corporation or of any creditor or stockholder thereof or on the
application of any receiver or receivers appointed for this Corporation under
the provisions of Section 291 of Title 8 of the Delaware Code or on the
application of trustees in dissolution or of any receiver or receivers appointed
for this Corporation under Section 279 of Title 8 of the Delaware Code order a
meeting of the creditors or class of creditors, and/or of the stockholders or
class of stockholders of this Corporation, as the case may be, to be summoned in
such manner as the said court directs. If a majority in number representing
three fourths in value of the creditors or class of creditors, and/or of the
stockholders or class of stockholders of this Corporation, as the case may be,
agree to any compromise or arrangement and to any reorganization of this
Corporation as consequence of such compromise or arrangement, the said
compromise or arrangement and the said reorganization shall, if sanctioned by
the court to which said application has been made, be binding on all the
creditors or class of creditors, and/or on all the stockholders or class of
stockholders, of this Corporation, as the case may be, and also on this
Corporation.
 
         SIXTH: The business and affairs of the Corporation shall be managed by
or under the direction of its Board of Directors. The number of directors which
shall constitute the entire Board of Directors shall be fixed by, or in the
manner provided in, the bylaws of this Corporation. The election of directors of
the Corporation need not be by written ballot, unless the bylaws so provide.
 
         SEVENTH: The Board of Directors is authorized to adopt, amend or repeal
the bylaws of the Corporation. The stockholders shall also have the power to
adopt, amend or repeal the bylaws of the Corporation. Notwithstanding, any
provision for the classification of directors for staggered terms pursuant to
Section 141(d) of the Delaware General Corporation Law shall be set forth in the
bylaws adopted by the stockholders unless provisions for such classification
shall be set forth in the Corporation's certificate of incorporation.
 
         EIGHTH: A director of the Corporation shall not be personally liable to
the Corporation or its stockholders for monetary damages for breach of fiduciary
 
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duty as a director except to the extent such exemption from liability or
limitation thereof is not permitted under the Delaware General Corporation Law
as the same exists or may hereafter be amended.
 
         Any repeal or modification of the foregoing paragraph shall not
adversely affect any right or protection of a director of the Corporation
existing hereunder with respect to any act or omission occurring prior to such
repeal or modification.
 
         NINTH: To the fullest extent permitted by Section 145 of the General
Corporation Law of Delaware as the same exists or may hereafter be amended, the
Corporation shall indemnify any and all persons whom it shall have power to
indemnify under said section from and against any and all of the expenses,
liabilities or other matters referred to in or covered by said section, and the
indemnification provided for hereby shall not be deemed exclusive of any other
rights to which those indemnified may be entitled under any bylaw, agreement,
vote of stockholders or disinterested directors or otherwise, both as to any
action such person may have performed in current official capacity or in another
capacity while holding such office, and shall continue as to any person who has
ceased to be a director, officer, employee or agent and shall inure to the
benefit of heirs, executors and administrators of such person. No repeal or
modification of this Section by the stockholders of the Corporation shall
adversely affect any right of protection existing by virtue of this Section at
the time of such repeal or modification.
 
         IN WITNESS WHEREOF, the Corporation has caused this Sixth Amended and
Restated Certificate of Incorporation to be signed by its duly authorized
officer this -- day of -------, 2005.
 
 
                                       THERMOGENESIS CORP.
 
 
                                       ---------------------------------
                                       Philip H. Coelho, Chairman & CEO