SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549

                                    Form 8-K

                Current Report Pursuant to Section 13 or 15(d) of
                       The Securities Exchange Act of 1934

       Date of Report (Date of earliest event reported) December 23, 1999

                               THERMOGENESIS CORP.
             (Exact name of registrant as specified in its charter)

            Delaware                     0-16375                   94-3018487
-------------------------------   ---------------------     --------------------
(State or other jurisdiction of   (Commission File No.)       (I.R.S. Employer
incorporation or organization)                               Identification No.)


                              3146 Gold Camp Drive
                        Rancho Cordova, California 95670
                                 (916) 858-5100
           ------------------------------------------------------------
          (Address and telephone number of principal executive offices)

Item 5.  Other Events

On January 4, 2000, THERMOGENESIS CORP. completed an offering of 4,040 shares of
Series B Convertible  Preferred Stock and warrants to purchase 444,562 shares of
THERMOGENESIS  CORP.  common stock.  The initial  placement was made to the lead
investors, Advantage Fund II Ltd. and Koch Investment Group Limited, on December
22, 1999, and the final closing was held on January 4, 2000 with Clarion Capital
Corporation.  The placement resulted in gross proceeds to THERMOGENESIS CORP. of
$4,040,000,  before  commissions  and expenses  payable in  connection  with the
placement.

Unless  stockholder  approval is obtained,  the Series B  Convertible  Preferred
Stock is convertible into a maximum of 4,236,000  shares of THERMOGENESIS  CORP.
common stock, in the aggregate. For the first six months from December 22, 1999,
the Series B Convertible  Preferred  Stock is convertible at a fixed  conversion
price of $2.2719 per common share, which represents the average bid price of the
common  stock for the ten days  prior to  December  22,  1999.  Thereafter,  the
conversion  price is  adjusted  every six months to be the lesser of (a) 130% of
the fixed  conversion  price or (b) 90% of the average  market price for the ten
days prior to such adjustment date. The Series B Convertible  Preferred Stock is
entitled to dividends at the rate of 6% per annum which amount, at the option of
THERMOGENESIS  CORP.,  may be added to the $1,000 per share  conversion value of
the Series B Convertible Preferred Stock.

The   conversion   price  is  subject  to  further   adjustment   under  certain
circumstances, provided such circumstances are outside of the Company's control,
as set  forth  in the  Certificate  of  Designations  of  Series  B  Convertible
Preferred Stock attached to this current report, including the following events:
(i) no closing bid price for the common stock for five consecutive trading days;
(ii) delisting of the common stock from the Nasdaq  SmallCap Market or any other
market or exchange;  (iii)  inability of the  investors to sell shares of common
stock  pursuant to an effective  registration  statement for 30 days or more, in
the aggregate; (iv)


<PAGE>2



certain business  combination events where THERMOGENESIS  CORP.  stockholders do
not  control  51%  of  the  combined  company,  unless  certain  conditions  are
satisfied; and (v) certain defaults by THERMOGENESIS CORP. in the performance of
its obligations to the  institutions;  and (iv) the adoption of any amendment to
THERMOGENESIS  CORP.'s  Certificate of Incorporation  materially  adverse to the
holders of the Series B Convertible  Preferred  Stock without the consent of the
majority of the shares of Series B Convertible Preferred Stock. If THERMOGENESIS
CORP. takes action to affect any of the foregoing,  and such action is deemed to
be within its control, the Series B holders can require that THERMOGENESIS CORP.
redeem the shares at a premium.

THERMOGENESIS  CORP. has the right to redeem the Series B Convertible  Preferred
Stock at a premium  and under  some  circumstances  at the  market  price of its
common stock that the Series B Convertible  Preferred  Stock would  otherwise be
convertible into.

The net proceeds from the offering will be used for general  corporate  purposes
and working capital.

The terms of the  private  placement  are set forth in the form of  Subscription
Agreement  attached as Exhibit 10 to this current  report.  The  Certificate  of
Designations of Series B Convertible Preferred Stock is also attached as Exhibit
4.1 to this current report, and contains the rights, preferences, privileges and
restrictions of the Series B Convertible Preferred Stock. The Warrants issued in
connection  with the placement are subject to the terms contained in the Form of
Warrant  attached as Exhibit 4.2 to this current report.  Under the Registration
Rights  Agreement,  entered  into with each  Series B investor  and  attached as
Exhibit  4.3,  THERMOGENESIS  CORP.  has  agreed  to  prepare  and file with the
Securities and Exchange Commission a registration  statement covering the resale
of the shares of common  stock  underlying  the Series B  Convertible  Preferred
Stock and warrants.

In connection with the placement of  THERMOGENESIS  CORP.'s Series B Convertible
Preferred Stock,  THERMOGENESIS  CORP. paid a 6% commission and issued a warrant
to purchase  40,000  shares of common  stock to  Reedland  Capital  Partners,  a
Division of Financial West Group. The warrants issued to Advantage Fund II Ltd.,
Koch Investment  Group Limited,  Clarion Capital  Corporation,  and Reedland are
exercisable for a period of five years at an exercise price of $2.72628.

Item 7. Financial Statements, Pro Forma Financial Information, and Exhibits

        (c)     EXHIBITS

Exhibit
Number                 Description
-------                ------------
 4.1                   Certificate of Designations of Series B Convertible
                       Preferred Stock, dated December 22, 1999
 4.2                   Warrant [Form]
 4.3                   Registration Rights Agreement, dated December 22, 1999
                       [Form]
 10.                   Subscription Agreement, dated December 22, 1999 [Form]


<PAGE>3


                                           SIGNATURE


     Pursuant to the  requirements  of the Securities  Exchange Act of 1934, the
registrant  has duly  caused  this  report  to be  signed  on its  behalf by the
undersigned hereunto duly authorized.


Dated: January 4, 2000                       THERMOGENESIS CORP.
                                             a Delaware Corporation


                                       /s/   PHILIP H. COELHO
                                             --------------------------------
                                             Philip H. Coelho, Chairman & CEO
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SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549

                                    Form 8-K

                Current Report Pursuant to Section 13 or 15(d) of
                       The Securities Exchange Act of 1934

       Date of Report (Date of earliest event reported) December 23, 1999

                               THERMOGENESIS CORP.
             (Exact name of registrant as specified in its charter)

            Delaware                     0-16375                   94-3018487
-------------------------------   ---------------------     --------------------
(State or other jurisdiction of   (Commission File No.)       (I.R.S. Employer
incorporation or organization)                               Identification No.)

                              3146 Gold Camp Drive
                        Rancho Cordova, California 95670
                                 (916) 858-5100
           ------------------------------------------------------------
          (Address and telephone number of principal executive offices)

Item 5.  Other Events

On January 4, 2000, THERMOGENESIS CORP. completed an offering of 4,040 shares of
Series B Convertible  Preferred Stock and warrants to purchase 444,562 shares of
THERMOGENESIS  CORP.  common stock.  The initial  placement was made to the lead
investors, Advantage Fund II Ltd. and Koch Investment Group Limited, on December
22, 1999, and the final closing was held on January 4, 2000 with Clarion Capital
Corporation.  The placement resulted in gross proceeds to THERMOGENESIS CORP. of
$4,040,000,  before  commissions  and expenses  payable in  connection  with the
placement.

Unless  stockholder  approval is obtained,  the Series B  Convertible  Preferred
Stock is convertible into a maximum of 4,236,000  shares of THERMOGENESIS  CORP.
common stock, in the aggregate. For the first six months from December 22, 1999,
the Series B Convertible  Preferred  Stock is convertible at a fixed  conversion
price of $2.2719 per common share, which represents the average bid price of the
common  stock for the ten days  prior to  December  22,  1999.  Thereafter,  the
conversion  price is  adjusted  every six months to be the lesser of (a) 130% of
the fixed  conversion  price or (b) 90% of the average  market price for the ten
days prior to such adjustment date. The Series B Convertible  Preferred Stock is
entitled to dividends at the rate of 6% per annum which amount, at the option of
THERMOGENESIS  CORP.,  may be added to the $1,000 per share  conversion value of
the Series B Convertible Preferred Stock.

The   conversion   price  is  subject  to  further   adjustment   under  certain
circumstances, provided such circumstances are outside of the Company's control,
as set  forth  in the  Certificate  of  Designations  of  Series  B  Convertible
Preferred Stock attached to this current report, including the following events:
(i) no closing bid price for the common stock for five consecutive trading days;
(ii) delisting of the common stock from the Nasdaq  SmallCap Market or any other
market or exchange;  (iii)  inability of the  investors to sell shares of common
stock  pursuant to an effective  registration  statement for 30 days or more, in
the aggregate; (iv)
2

certain business  combination events where THERMOGENESIS  CORP.  stockholders do
not  control  51%  of  the  combined  company,  unless  certain  conditions  are
satisfied; and (v) certain defaults by THERMOGENESIS CORP. in the performance of
its obligations to the  institutions;  and (iv) the adoption of any amendment to
THERMOGENESIS  CORP.'s  Certificate of Incorporation  materially  adverse to the
holders of the Series B Convertible  Preferred  Stock without the consent of the
majority of the shares of Series B Convertible Preferred Stock. If THERMOGENESIS
CORP. takes action to affect any of the foregoing,  and such action is deemed to
be within its control, the Series B holders can require that THERMOGENESIS CORP.
redeem the shares at a premium.

THERMOGENESIS  CORP. has the right to redeem the Series B Convertible  Preferred
Stock at a premium  and under  some  circumstances  at the  market  price of its
common stock that the Series B Convertible  Preferred  Stock would  otherwise be
convertible into.

The net proceeds from the offering will be used for general  corporate  purposes
and working capital.

The terms of the  private  placement  are set forth in the form of  Subscription
Agreement  attached as Exhibit 10 to this current  report.  The  Certificate  of
Designations of Series B Convertible Preferred Stock is also attached as Exhibit
4.1 to this current report, and contains the rights, preferences, privileges and
restrictions of the Series B Convertible Preferred Stock. The Warrants issued in
connection  with the placement are subject to the terms contained in the Form of
Warrant  attached as Exhibit 4.2 to this current report.  Under the Registration
Rights  Agreement,  entered  into with each  Series B investor  and  attached as
Exhibit  4.3,  THERMOGENESIS  CORP.  has  agreed  to  prepare  and file with the
Securities and Exchange Commission a registration  statement covering the resale
of the shares of common  stock  underlying  the Series B  Convertible  Preferred
Stock and warrants.

In connection with the placement of  THERMOGENESIS  CORP.'s Series B Convertible
Preferred Stock,  THERMOGENESIS  CORP. paid a 6% commission and issued a warrant
to purchase  40,000  shares of common  stock to  Reedland  Capital  Partners,  a
Division of Financial West Group. The warrants issued to Advantage Fund II Ltd.,
Koch Investment  Group Limited,  Clarion Capital  Corporation,  and Reedland are
exercisable for a period of five years at an exercise price of $2.72628.

Item 7. Financial Statements, Pro Forma Financial Information, and Exhibits

        (c)     EXHIBITS

Exhibit
Number                 Description
-------                ------------
 4.1                   Certificate of Designations of Series B Convertible
                       Preferred Stock, dated December 22, 1999
 4.2                   Warrant [Form]
 4.3                   Registration Rights Agreement, dated December 22, 1999
                       [Form]
 10.                   Subscription Agreement, dated December 22, 1999 [Form]
3

                                           SIGNATURE

     Pursuant to the  requirements  of the Securities  Exchange Act of 1934, the
registrant  has duly  caused  this  report  to be  signed  on its  behalf by the
undersigned hereunto duly authorized.

Dated: January 4, 2000                       THERMOGENESIS CORP.
                                             a Delaware Corporation

                                       /s/   PHILIP H. COELHO
                                             --------------------------------
                                             Philip H. Coelho, Chairman & CEO